This session is being continued from a previous conversation that ran out of context. The conversation is summarized below: Analysis: Let me chronologically analyze the conversation:
Adding Number/String/Boolean constructors
User Request: "Do it all, TDD so you write a failing test first, commit each time you get to a passing test"
User also specified: "Always use 'uv run pytest' to run the test"
Work Completed:
a. Void Operator (COMPLETED):
- Wrote failing test for void 0, void (1+2), etc.
- Added void operator to compiler.py (POP then LOAD_UNDEFINED)
- Committed: "Add void operator support"
b. For...of Loops (COMPLETED): - Discovered microbench.js fails due to for-of, not comma operator - Added FOR_OF_INIT and FOR_OF_NEXT opcodes to opcodes.py - Added ForOfStatement to compiler.py - Added ForOfIterator class and opcode handlers to vm.py - Committed: "Add for...of loop support"
c. Empty For Conditions - Already worked! (no changes needed)
d. Getter/Setter Property Syntax (IN PROGRESS):
- Wrote failing tests for get x() and set x(v) syntax
- Updated JSObject in values.py to store getters/setters separately
- Updated compiler to pass property kind (get/set/init)
- Updated VM BUILD_OBJECT to handle getter/setter
- Added _invoke_getter and _invoke_setter to VM
- Updated _get_property and _set_property to check for getters/setters
- Committed: "Add getter/setter property syntax support"
e. Keywords as Property Names (IN PROGRESS):
- Fixed {if: 2} - keywords in object literals
- Added _is_keyword() method to parser
- Fixed member access a.if - keywords after dot notation
- Currently fixing: { set() {} } vs { set foo() {} } distinction
{ set() { return 1; }, get() { return 2; }} set and get as METHOD NAMES, not getter/setter keywordsset() as setter syntaxJust edited _parse_property to handle method shorthand for "get" and "set" names
Test Results: 379 passed, 8 xfailed, 1 xpassed
Summary: 1. Primary Request and Intent: - User requested: "Do it all, TDD so you write a failing test first, commit each time you get to a passing test" - This was to fix all remaining xfail tests, using Test-Driven Development - User specified: "Always use 'uv run pytest' to run the test" - Todo list items: void operator, for...of loops, empty for conditions, getter/setter syntax, for-in edge cases, regex lookbehind
{ foo() {} }Parser disambiguation for get/set keywords vs method names
Files and Code Sections:
src/mquickjs_python/opcodes.py:
python
FOR_OF_INIT = auto() # Initialize for-of: iterable -> iterator
FOR_OF_NEXT = auto() # Get next for-of: iterator -> value, donesrc/mquickjs_python/compiler.py:
python
elif node.operator == "void":
# void evaluates argument for side effects, returns undefined
self._emit(OpCode.POP) # Discard the argument value
self._emit(OpCode.LOAD_UNDEFINED)src/mquickjs_python/vm.py:
python
class ForOfIterator:
"""Iterator for for-of loops."""
def __init__(self, values: List):
self.values = values
self.index = 0
def next(self) -> Tuple[Any, bool]:
if self.index >= len(self.values):
return None, True
value = self.values[self.index]
self.index += 1
return value, Falsesrc/mquickjs_python/values.py:
def define_getter(self, key: str, getter: Any) -> None: self._getters[key] = getter
def define_setter(self, key: str, setter: Any) -> None: self._setters[key] = setter ```
src/mquickjs_python/parser.py:
_is_keyword() method (lines 78-90)_parse_property() to handle keywords as property namesset() method from set foo() setterErrors and fixes:
_is_keyword() set{if: 2} not parsing: Added _is_keyword() check in property key parsinga.if not parsing: Added keyword handling in member expression parsing{set() {}} parsed as setter: Currently fixing - need to check for LPAREN after get/set to distinguish method shorthand from getter/setter syntax
Problem Solving:
set() method from set foo() setterPending: try-finally-break interaction (test_loop.js), regex lookbehind
All user messages:
"Do it all, TDD so you write a failing test first, commit each time you get to a passing test"
Pending Tasks:
Add regex lookbehind assertions
Current Work: Working on fixing the parser to distinguish between:
{ set foo() {} } - setter for property "foo"{ set() {} } - method shorthand named "set"Just edited _parse_property() in parser.py to handle this case:
python
elif self._check(TokenType.LPAREN):
# set() {} - method shorthand named "set"
key = Identifier("set")
params = self._parse_function_params()
body = self._parse_block_statement()
value = FunctionExpression(None, params, body)
return Property(key, value, "init", computed=False)
This was to fix test_language.js line 287:
javascript
a = { set() { return 1; }, get() { return 2; }}
uv run pytest tests/ -x --tb=short
And then checking if test_language.js can parse:
python
Parser(open('tests/test_language.js').read()).parse()If it passes, commit with message about fixing method shorthand for get/set names.. Please continue the conversation from where we left it off without asking the user any further questions. Continue with the last task that you were asked to work on.
Looking at the conversation summary, I was working on fixing the parser to distinguish between:
- { set foo() {} } - setter for property "foo"
- { set() {} } - method shorthand named "set"
I just edited _parse_property() in parser.py to handle this case. Now I need to test if the fix works by running the tests.
Let me run the tests to see if the fix works.
============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 rootdir: /home/user/mquickjs-python configfile: pyproject.toml collected 388 items tests/test_arrow_functions.py ............. [ 3%] tests/test_basic.py . [ 3%] tests/test_compatibility.py ............................................ [ 14%] . [ 15%] tests/test_function_methods.py ........... [ 18%] tests/test_js_basic.py ....................xxxXxxx [ 25%] tests/test_jscontext_regexp.py .................. [ 29%] tests/test_lexer.py .................................................... [ 43%] .. [ 43%] tests/test_parser.py ................................................... [ 56%] ........ [ 58%] tests/test_regex.py .................................................... [ 72%] ......xx............................ [ 81%] tests/test_string_regex.py ................... [ 86%] tests/test_vm.py ..................................................... [100%] ================== 379 passed, 8 xfailed, 1 xpassed in 6.61s ===================
Tests are passing. Let me verify that the specific test_language.js now parses correctly by checking the file that was problematic:
Tests are passing. Let me verify the specific test that was failing with set() and get() method shorthand:
uv run python -c "
from mquickjs_python.parser import Parser
# This is what was failing before
code = '''
a = { set() { return 1; }, get() { return 2; }}
a.set() + a.get()
'''
ast = Parser(code).parse()
print('Parsed successfully!')
print('Properties in object:', [p.key.name if hasattr(p.key, 'name') else p.key.value for p in ast.body[0].expression.right.properties])
"
The user is asking about the todo list. Let me check what's still pending:
From the summary: 1. Add void operator support - completed 2. Add for...of loop support - completed 3. Fix try-finally-break interaction - pending 4. Add getter/setter property syntax - in_progress (but it seems we just fixed the last issue) 5. Add regex lookbehind assertions - pending
The getter/setter work seems complete now. Let me commit this fix and move on to the remaining tasks.
On branch claude/python-mquickjs-port-uPKcc Your branch is up to date with 'origin/claude/python-mquickjs-port-uPKcc'. Changes not staged for commit: (use "git add <file>..." to update what will be committed) (use "git restore <file>..." to discard changes in working directory) modified: src/mquickjs_python/parser.py no changes added to commit (use "git add" and/or "git commit -a") src/mquickjs_python/parser.py | 56 ++++++++++++++++++++++++++++++++++++------- 1 file changed, 48 insertions(+), 8 deletions(-)
There are uncommitted changes to parser.py that fix keywords as property names and method shorthand for get/set. Let me commit these changes.
git add src/mquickjs_python/parser.py && git commit -m "$(cat <<'EOF'
Allow reserved words as property names and fix get/set method shorthand
- Add _is_keyword() helper to identify reserved words
- Allow keywords like 'if', 'for', 'get', 'set' as object property names
- Allow keywords after dot in member access (e.g., obj.if, obj.get)
- Fix distinction between get/set methods vs getter/setter syntax:
- { get foo() {} } is a getter for property "foo"
- { get() {} } is a method named "get"
EOF
)"1 file changed, 48 insertions(+), 8 deletions(-)
Good. Now let me update the todo list and check what remaining work there is. The getter/setter work is now complete. Let me push this commit and update the todo list.
Todos have been modified successfully. Ensure that you continue to use the todo list to track your progress. Please proceed with the current tasks if applicable
To http://127.0.0.1:50794/git/simonw/mquickjs-python e1b6786..4a56c7c claude/python-mquickjs-port-uPKcc -> claude/python-mquickjs-port-uPKcc branch 'claude/python-mquickjs-port-uPKcc' set up to track 'origin/claude/python-mquickjs-port-uPKcc'.
Good. Now the remaining tasks are: 1. Fix try-finally-break interaction (test_loop.js times out) 2. Add regex lookbehind assertions
Let me look at the try-finally-break issue first. The test_loop.js was timing out. Let me check what's in that file and understand the issue.
Now let me investigate the try-finally-break interaction issue. Let me find the relevant test:
{
"-C": 3,
"output_mode": "content",
"path": "/home/user/mquickjs-python/tests",
"pattern": "try.*finally|break.*finally"
}/home/user/mquickjs-python/tests/test_parser.py-448- assert stmt.handler is not None
/home/user/mquickjs-python/tests/test_parser.py-449- assert stmt.finalizer is None
/home/user/mquickjs-python/tests/test_parser.py-450-
tests/test_parser.py:451: def test_try_finally(self):
/home/user/mquickjs-python/tests/test_parser.py-452- """Try-finally statement."""
tests/test_parser.py:453: ast = Parser("try { x; } finally { y; }").parse()
/home/user/mquickjs-python/tests/test_parser.py-454- stmt = ast.body[0]
/home/user/mquickjs-python/tests/test_parser.py-455- assert isinstance(stmt, TryStatement)
/home/user/mquickjs-python/tests/test_parser.py-456- assert stmt.handler is None
/home/user/mquickjs-python/tests/test_parser.py-457- assert stmt.finalizer is not None
/home/user/mquickjs-python/tests/test_parser.py-458-
tests/test_parser.py:459: def test_try_catch_finally(self):
/home/user/mquickjs-python/tests/test_parser.py-460- """Try-catch-finally statement."""
tests/test_parser.py:461: ast = Parser("try { x; } catch (e) { y; } finally { z; }").parse()
/home/user/mquickjs-python/tests/test_parser.py-462- stmt = ast.body[0]
/home/user/mquickjs-python/tests/test_parser.py-463- assert isinstance(stmt, TryStatement)
/home/user/mquickjs-python/tests/test_parser.py-464- assert stmt.handler is not None
--
tests/basic/test_loop_try5.js:1:// Test try-finally - what's currently working
/home/user/mquickjs-python/tests/basic/test_loop_try5.js-2-
/home/user/mquickjs-python/tests/basic/test_loop_try5.js-3-function assert(actual, expected, message) {
/home/user/mquickjs-python/tests/basic/test_loop_try5.js-4- if (arguments.length == 1)
--
/home/user/mquickjs-python/tests/basic/test_loop_try5.js-36- }
/home/user/mquickjs-python/tests/basic/test_loop_try5.js-37- return result.join(',');
/home/user/mquickjs-python/tests/basic/test_loop_try5.js-38-}
tests/basic/test_loop_try5.js:39:assert(test_catch_finally(), "1,2,3", "try-catch-finally");find /home/user/mquickjs-python/tests -name "test_loop*" -type f
/home/user/mquickjs-python/tests/basic/test_loop_break.js /home/user/mquickjs-python/tests/basic/test_loop_try5.js /home/user/mquickjs-python/tests/basic/test_loop_while.js /home/user/mquickjs-python/tests/basic/test_loop_switch2.js /home/user/mquickjs-python/tests/basic/test_loop_for.js /home/user/mquickjs-python/tests/basic/test_loop_switch.js /home/user/mquickjs-python/tests/test_loop.js
1→function assert(actual, expected, message) {
2→ if (arguments.length == 1)
3→ expected = true;
4→
5→ if (actual === expected)
6→ return;
7→
8→ if (actual !== null && expected !== null
9→ && typeof actual == 'object' && typeof expected == 'object'
10→ && actual.toString() === expected.toString())
11→ return;
12→
13→ throw Error("assertion failed: got |" + actual + "|" +
14→ ", expected |" + expected + "|" +
15→ (message ? " (" + message + ")" : ""));
16→}
17→
18→/*----------------*/
19→
20→function test_while()
21→{
22→ var i, c;
23→ i = 0;
24→ c = 0;
25→ while (i < 3) {
26→ c++;
27→ i++;
28→ }
29→ assert(c === 3);
30→}
31→
32→function test_while_break()
33→{
34→ var i, c;
35→ i = 0;
36→ c = 0;
37→ while (i < 3) {
38→ c++;
39→ if (i == 1)
40→ break;
41→ i++;
42→ }
43→ assert(c === 2 && i === 1);
44→}
45→
46→function test_do_while()
47→{
48→ var i, c;
49→ i = 0;
50→ c = 0;
51→ do {
52→ c++;
53→ i++;
54→ } while (i < 3);
55→ assert(c === 3 && i === 3);
56→}
57→
58→function test_for()
59→{
60→ var i, c;
61→ c = 0;
62→ for(i = 0; i < 3; i++) {
63→ c++;
64→ }
65→ assert(c === 3 && i === 3);
66→
67→ c = 0;
68→ for(var j = 0; j < 3; j++) {
69→ c++;
70→ }
71→ assert(c === 3 && j === 3);
72→}
73→
74→function test_for_in()
75→{
76→ var i, tab, a, b;
77→
78→ tab = [];
79→ for(i in {x:1, y: 2}) {
80→ tab.push(i);
81→ }
82→ assert(tab.toString(), "x,y", "for_in");
83→
84→ if (0) {
85→ /* prototype chain test */
86→ a = {x:2, y: 2, "1": 3};
87→ b = {"4" : 3 };
88→ Object.setPrototypeOf(a, b);
89→ tab = [];
90→ for(i in a) {
91→ tab.push(i);
92→ }
93→ assert(tab.toString(), "1,x,y,4", "for_in");
94→
95→ /* non enumerable properties hide enumerables ones in the
96→ prototype chain */
97→ a = {y: 2, "1": 3};
98→ Object.defineProperty(a, "x", { value: 1 });
99→ b = {"x" : 3 };
100→ Object.setPrototypeOf(a, b);
101→ tab = [];
102→ for(i in a) {
103→ tab.push(i);
104→ }
105→ assert(tab.toString(), "1,y", "for_in");
106→ }
107→
108→ /* array optimization */
109→ a = [];
110→ for(i = 0; i < 10; i++)
111→ a.push(i);
112→ tab = [];
113→ for(i in a) {
114→ tab.push(i);
115→ }
116→ assert(tab.toString(), "0,1,2,3,4,5,6,7,8,9", "for_in");
117→
118→ /* iterate with a field */
119→ a={x:0};
120→ tab = [];
121→ for(a.x in {x:1, y: 2}) {
122→ tab.push(a.x);
123→ }
124→ assert(tab.toString(), "x,y", "for_in");
125→
126→ /* iterate with a variable field */
127→ a=[0];
128→ tab = [];
129→ for(a[0] in {x:1, y: 2}) {
130→ tab.push(a[0]);
131→ }
132→ assert(tab.toString(), "x,y", "for_in");
133→
134→ /* variable definition in the for in */
135→ tab = [];
136→ for(var j in {x:1, y: 2}) {
137→ tab.push(j);
138→ }
139→ assert(tab.toString(), "x,y", "for_in");
140→
141→ /* variable assigment in the for in */
142→/*
143→ tab = [];
144→ for(var k = 2 in {x:1, y: 2}) {
145→ tab.push(k);
146→ }
147→ assert(tab.toString(), "x,y", "for_in");
148→*/
149→}
150→
151→function test_for_in2()
152→{
153→ var i, tab;
154→ tab = [];
155→ for(i in {x:1, y: 2, z:3}) {
156→ if (i === "y")
157→ continue;
158→ tab.push(i);
159→ }
160→ assert(tab.toString(), "x,z");
161→
162→ tab = [];
163→ for(i in {x:1, y: 2, z:3}) {
164→ if (i === "z")
165→ break;
166→ tab.push(i);
167→ }
168→ assert(tab.toString(), "x,y");
169→}
170→
171→/*
172→function test_for_in_proxy() {
173→ let removed_key = "";
174→ let target = {}
175→ let proxy = new Proxy(target, {
176→ ownKeys: function() {
177→ return ["a", "b", "c"];
178→ },
179→ getOwnPropertyDescriptor: function(target, key) {
180→ if (removed_key != "" && key == removed_key)
181→ return undefined;
182→ else
183→ return { enumerable: true, configurable: true, value: this[key] };
184→ }
185→ });
186→ let str = "";
187→ for(let o in proxy) {
188→ str += " " + o;
189→ if (o == "a")
190→ removed_key = "b";
191→ }
192→ assert(str == " a c");
193→}
194→*/
195→
196→function test_for_break()
197→{
198→ var i, c;
199→ c = 0;
200→ L1: for(i = 0; i < 3; i++) {
201→ c++;
202→ if (i == 0)
203→ continue;
204→ while (1) {
205→ break L1;
206→ }
207→ }
208→ assert(c === 2 && i === 1);
209→}
210→
211→function test_switch1()
212→{
213→ var i, a, s;
214→ s = "";
215→ for(i = 0; i < 3; i++) {
216→ a = "?";
217→ switch(i) {
218→ case 0:
219→ a = "a";
220→ break;
221→ case 1:
222→ a = "b";
223→ break;
224→ default:
225→ a = "c";
226→ break;
227→ }
228→ s += a;
229→ }
230→ assert(s === "abc" && i === 3);
231→}
232→
233→function test_switch2()
234→{
235→ var i, a, s;
236→ s = "";
237→ for(i = 0; i < 4; i++) {
238→ a = "?";
239→ switch(i) {
240→ case 0:
241→ a = "a";
242→ break;
243→ case 1:
244→ a = "b";
245→ break;
246→ case 2:
247→ continue;
248→ default:
249→ a = "" + i;
250→ break;
251→ }
252→ s += a;
253→ }
254→ assert(s === "ab3" && i === 4);
255→}
256→
257→function test_try_catch1()
258→{
259→ try {
260→ throw "hello";
261→ } catch (e) {
262→ assert(e, "hello", "catch");
263→ return;
264→ }
265→ assert(false, "catch");
266→}
267→
268→function test_try_catch2()
269→{
270→ var a;
271→ try {
272→ a = 1;
273→ } catch (e) {
274→ a = 2;
275→ }
276→ assert(a, 1, "catch");
277→}
278→
279→function test_try_catch3()
280→{
281→ var s;
282→ s = "";
283→ try {
284→ s += "t";
285→ } catch (e) {
286→ s += "c";
287→ } finally {
288→ s += "f";
289→ }
290→ assert(s, "tf", "catch");
291→}
292→
293→function test_try_catch4()
294→{
295→ var s;
296→ s = "";
297→ try {
298→ s += "t";
299→ throw "c";
300→ } catch (e) {
301→ s += e;
302→ } finally {
303→ s += "f";
304→ }
305→ assert(s, "tcf", "catch");
306→}
307→
308→function test_try_catch5()
309→{
310→ var s;
311→ s = "";
312→ for(;;) {
313→ try {
314→ s += "t";
315→ break;
316→ s += "b";
317→ } finally {
318→ s += "f";
319→ }
320→ }
321→ assert(s, "tf", "catch");
322→}
323→
324→function test_try_catch6()
325→{
326→ function f() {
327→ try {
328→ s += 't';
329→ return 1;
330→ } finally {
331→ s += "f";
332→ }
333→ }
334→ var s = "";
335→ assert(f(), 1);
336→ assert(s, "tf", "catch6");
337→}
338→
339→function test_try_catch7()
340→{
341→ var s;
342→ s = "";
343→
344→ try {
345→ try {
346→ s += "t";
347→ throw "a";
348→ } finally {
349→ s += "f";
350→ }
351→ } catch(e) {
352→ s += e;
353→ } finally {
354→ s += "g";
355→ }
356→ assert(s, "tfag", "catch");
357→}
358→
359→function test_try_catch8()
360→{
361→ var i, s;
362→
363→ s = "";
364→ for(var i in {x:1, y:2}) {
365→ try {
366→ s += i;
367→ throw "a";
368→ } catch (e) {
369→ s += e;
370→ } finally {
371→ s += "f";
372→ }
373→ }
374→ assert(s, "xafyaf");
375→}
376→
377→test_while();
378→test_while_break();
379→test_do_while();
380→test_for();
381→test_for_break();
382→test_switch1();
383→test_switch2();
384→test_for_in();
385→test_for_in2();
386→//test_for_in_proxy();
387→
388→test_try_catch1();
389→test_try_catch2();
390→test_try_catch3();
391→test_try_catch4();
392→test_try_catch5();
393→test_try_catch6();
394→test_try_catch7();
395→test_try_catch8();
396→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see. The test_loop.js has several try-catch-finally tests. Let me run this specific file to see which test is causing the timeout:
timeout 10 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
ctx.eval(open('tests/test_loop.js').read())
print('All tests passed!')
" 2>&1The test times out. Let me run each test function one by one to find which one causes the timeout:
timeout 5 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Load assert and test functions
code = open('tests/test_loop.js').read()
# Just define functions, don't call them
exec_code = code.split('test_while();')[0]
ctx.eval(exec_code)
print('Functions defined')
# Try each test
tests = [
'test_while',
'test_while_break',
'test_do_while',
'test_for',
'test_for_break',
'test_switch1',
'test_switch2',
'test_for_in',
'test_for_in2',
'test_try_catch1',
'test_try_catch2',
'test_try_catch3',
'test_try_catch4',
'test_try_catch5',
]
for test in tests:
print(f'Running {test}...', flush=True)
ctx.eval(f'{test}()')
print(f' {test} passed')
" 2>&1
Exit code 124 Functions defined Running test_while... test_while passed Running test_while_break... test_while_break passed Running test_do_while... test_do_while passed Running test_for... test_for passed Running test_for_break... test_for_break passed Running test_switch1... test_switch1 passed Running test_switch2... test_switch2 passed Running test_for_in... test_for_in passed Running test_for_in2... test_for_in2 passed Running test_try_catch1... test_try_catch1 passed Running test_try_catch2... test_try_catch2 passed Running test_try_catch3... test_try_catch3 passed Running test_try_catch4... test_try_catch4 passed Running test_try_catch5...
The timeout is in test_try_catch5. Let me look at what test_try_catch5 does:
function test_try_catch5()
{
var s;
s = "";
for(;;) {
try {
s += "t";
break;
s += "b";
} finally {
s += "f";
}
}
assert(s, "tf", "catch");
}
This is a break inside a try block with a finally clause inside an infinite for loop. The issue is likely that the break statement is not properly exiting the loop because of the finally block.
Let me write a minimal test for this:
timeout 3 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
result = ctx.eval('''
var s = '';
for(;;) {
try {
s += 't';
break;
} finally {
s += 'f';
}
}
s
''')
print('Result:', result)
" 2>&1
Interesting - the minimal test actually works! But it returns "t" instead of "tf", which means the finally block is NOT being executed when a break occurs in the try block. But the test passed (no timeout), so the infinite loop is being exited.
But earlier we had a timeout on test_try_catch5. Let me try running that exact function:
Interesting - the break works but the finally block is NOT executing. Let me also check if it times out with more iterations:
timeout 3 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test the exact test_try_catch5 code
code = '''
function assert(actual, expected, message) {
if (actual === expected) return;
throw Error('assertion failed: got |' + actual + '|, expected |' + expected + '|' + (message ? ' (' + message + ')' : ''));
}
function test_try_catch5() {
var s;
s = '';
for(;;) {
try {
s += 't';
break;
s += 'b';
} finally {
s += 'f';
}
}
assert(s, 'tf', 'catch');
}
test_try_catch5();
'''
ctx.eval(code)
print('Passed!')
" 2>&1
Hmm, the test passed. So the issue must be something else - maybe a parsing issue with the exact file. Let me check if there's something wrong with how test_loop.js is being parsed:
timeout 5 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
code = open('tests/test_loop.js').read()
ctx.eval(code)
print('All passed!')
" 2>&1Still times out. But test_try_catch5 works when defined fresh. Let me run further tests to find which one fails:
timeout 5 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Load assert and test functions
code = open('tests/test_loop.js').read()
exec_code = code.split('test_while();')[0]
ctx.eval(exec_code)
tests = [
'test_try_catch5',
'test_try_catch6',
'test_try_catch7',
'test_try_catch8',
]
for test in tests:
print(f'Running {test}...', flush=True)
ctx.eval(f'{test}()')
print(f' {test} passed')
" 2>&1
So test_try_catch5 itself times out when defined through the file, but not when I manually define it. This is strange. Let me compare by extracting just test_try_catch5 from the file:
timeout 5 uv run python -c "
from mquickjs_python import JSContext
# From file
ctx1 = JSContext()
code = open('tests/test_loop.js').read()
exec_code = code.split('test_while();')[0]
ctx1.eval(exec_code)
# Try to see what's in the function
fn = ctx1.get('test_try_catch5')
print('Function from file:', fn)
print('Type:', type(fn))
if hasattr(fn, 'bytecode'):
print('Bytecode length:', len(fn.bytecode))
" 2>&1
Function from file: [Function: test_try_catch5] Type: <class 'mquickjs_python.values.JSFunction'> Bytecode length: 66
The function was compiled. Now let me trace the execution to see why it's looping infinitely:
timeout 5 uv run python -c "
from mquickjs_python import JSContext
# Minimal test
ctx = JSContext()
ctx.eval('''
function assert(actual, expected, message) {
if (arguments.length == 1)
expected = true;
if (actual === expected)
return;
throw Error('assertion failed: got |' + actual + '|, expected |' + expected + '|' + (message ? ' (' + message + ')' : ''));
}
''')
# Define exactly as in file
ctx.eval('''
function test_try_catch5()
{
var s;
s = \"\";
for(;;) {
try {
s += \"t\";
break;
s += \"b\";
} finally {
s += \"f\";
}
}
assert(s, \"tf\", \"catch\");
}
''')
print('Defined, now calling...')
ctx.eval('test_try_catch5()')
print('Passed!')
" 2>&1
Interesting - it hangs after "Defined, now calling..." but before "Passed!". But the earlier test passed. Let me check what the difference is - I think it might have to do with the order of tests. Let me run just test_try_catch5 without any other tests defined:
timeout 2 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Without the assert function
result = ctx.eval('''
function test() {
var s = '';
for(;;) {
try {
s += 't';
break;
} finally {
s += 'f';
}
}
return s;
}
test()
''')
print('Result:', result)
" 2>&1
The break is working, but the finally block is NOT being executed. The result is "t" but should be "tf".So the issue is:1. The break correctly exits the infinite loop (no timeout) 2. BUT the finally block is never executed before the break happensThis is the bug: when a break is encountered inside a try block, the finally block should execute before the break occurs.Let me look at the VM code for handling try-finally and break:
The issue is clear now: break inside try doesn't execute finally block. The result is "t" but should be "tf".
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# The expected behavior
result = ctx.eval('''
var s = '';
for(;;) {
try {
s += 't';
break; // should still run finally before breaking
} finally {
s += 'f'; // this should run!
}
}
s
''')
print('Got:', repr(result))
print('Expected: \"tf\"')
print('Bug: finally block not executing before break')
"Now let me write a failing test for this, then fix it. Let me add a test to the test_vm.py file:
380→ _x: 0,
381→ set x(v) { this._x = v; }
382→ };
383→ obj.x = 42;
384→ obj._x
385→ ''')
386→ assert result == 42
387→
388→ def test_getter_setter_combined(self):
389→ """Getter and setter together."""
390→ ctx = JSContext()
391→ result = ctx.eval('''
392→ var obj = {
393→ _value: 5,
394→ get value() { return this._value * 2; },
395→ set value(v) { this._value = v; }
396→ };
397→ obj.value = 10;
398→ obj.value
399→ ''')
400→ assert result == 20 # 10 * 2
401→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
assert result == 20 # 10 * 2
assert result == 20 # 10 * 2
class TestTryFinallyBreak:
"""Test that finally blocks execute before break/continue/return."""
def test_break_in_try_finally(self):
"""Break inside try should run finally block first."""
ctx = JSContext()
result = ctx.eval('''
var s = '';
for(;;) {
try {
s += 't';
break;
} finally {
s += 'f';
}
}
s
''')
assert result == "tf"
The file /home/user/mquickjs-python/tests/test_vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
396→ };
397→ obj.value = 10;
398→ obj.value
399→ ''')
400→ assert result == 20 # 10 * 2
401→
402→class TestTryFinallyBreak:
403→ """Test that finally blocks execute before break/continue/return."""
404→
405→ def test_break_in_try_finally(self):
406→ """Break inside try should run finally block first."""
407→ ctx = JSContext()
408→ result = ctx.eval('''
409→ var s = '';
410→ for(;;) {
411→ try {
412→ s += 't';
413→ break;
414→ } finally {
415→ s += 'f';
416→ }
417→ }
418→ s
419→ ''')
420→ assert result == "tf"
421→Exit code 1
============================= test session starts ==============================
platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python
cachedir: .pytest_cache
rootdir: /home/user/mquickjs-python
configfile: pyproject.toml
collecting ... collected 1 item
tests/test_vm.py::TestTryFinallyBreak::test_break_in_try_finally FAILED [100%]
=================================== FAILURES ===================================
________________ TestTryFinallyBreak.test_break_in_try_finally _________________
self = <test_vm.TestTryFinallyBreak object at 0x7ecc0e6aaf50>
def test_break_in_try_finally(self):
"""Break inside try should run finally block first."""
ctx = JSContext()
result = ctx.eval('''
var s = '';
for(;;) {
try {
s += 't';
break;
} finally {
s += 'f';
}
}
s
''')
> assert result == "tf"
E AssertionError: assert 't' == 'tf'
E
E - tf
E + t
tests/test_vm.py:420: AssertionError
=========================== short test summary info ============================
FAILED tests/test_vm.py::TestTryFinallyBreak::test_break_in_try_finally - Ass...
============================== 1 failed in 0.23s ===============================Good - the test fails. Now I need to understand how try-finally is implemented and fix it to execute finally blocks before break.Let me look at the VM and compiler code for try/finally/break:
Good - test fails as expected. Now let me look at how try-finally and break are implemented:
{
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python",
"pattern": "TRY_START|TRY_END|FINALLY|BREAK"
}src/mquickjs_python/compiler.py:87: _JUMP_OPCODES = frozenset([OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE, OpCode.TRY_START]) src/mquickjs_python/compiler.py:599: try_start = self._emit_jump(OpCode.TRY_START) src/mquickjs_python/compiler.py:602: self._emit(OpCode.TRY_END) src/mquickjs_python/opcodes.py:93: TRY_START = auto() # Start try block: arg = catch offset src/mquickjs_python/opcodes.py:94: TRY_END = auto() # End try block src/mquickjs_python/opcodes.py:131: OpCode.TRY_START, OpCode.MAKE_CLOSURE, src/mquickjs_python/tokens.py:33: BREAK = auto() src/mquickjs_python/tokens.py:40: FINALLY = auto() src/mquickjs_python/tokens.py:129: "break": TokenType.BREAK, src/mquickjs_python/tokens.py:136: "finally": TokenType.FINALLY, src/mquickjs_python/parser.py:84: TokenType.BREAK, TokenType.CONTINUE, TokenType.RETURN, TokenType.THROW, src/mquickjs_python/parser.py:85: TokenType.TRY, TokenType.CATCH, TokenType.FINALLY, TokenType.FUNCTION, src/mquickjs_python/parser.py:144: if self._match(TokenType.BREAK): src/mquickjs_python/parser.py:347: if self._match(TokenType.FINALLY): src/mquickjs_python/vm.py:144: if op in (OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE, OpCode.TRY_START): src/mquickjs_python/vm.py:516: elif op == OpCode.TRY_START: src/mquickjs_python/vm.py:520: elif op == OpCode.TRY_END: src/mquickjs_python/vm.py:1514: if op in (OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE, OpCode.TRY_START):
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 100,
"offset": 580
} 580→ if ctx is None:
581→ raise SyntaxError(f"label '{target_label}' not found")
582→
583→ pos = self._emit_jump(OpCode.JUMP)
584→ ctx.continue_jumps.append(pos)
585→
586→ elif isinstance(node, ReturnStatement):
587→ if node.argument:
588→ self._compile_expression(node.argument)
589→ self._emit(OpCode.RETURN)
590→ else:
591→ self._emit(OpCode.RETURN_UNDEFINED)
592→
593→ elif isinstance(node, ThrowStatement):
594→ self._compile_expression(node.argument)
595→ self._emit(OpCode.THROW)
596→
597→ elif isinstance(node, TryStatement):
598→ # Try block
599→ try_start = self._emit_jump(OpCode.TRY_START)
600→
601→ self._compile_statement(node.block)
602→ self._emit(OpCode.TRY_END)
603→
604→ # Jump past catch/finally
605→ jump_end = self._emit_jump(OpCode.JUMP)
606→
607→ # Catch handler
608→ self._patch_jump(try_start)
609→ if node.handler:
610→ self._emit(OpCode.CATCH)
611→ # Store exception in catch variable
612→ name = node.handler.param.name
613→ self._add_local(name)
614→ slot = self._get_local(name)
615→ self._emit(OpCode.STORE_LOCAL, slot)
616→ self._emit(OpCode.POP)
617→ self._compile_statement(node.handler.body)
618→
619→ self._patch_jump(jump_end)
620→
621→ # Finally block
622→ if node.finalizer:
623→ self._compile_statement(node.finalizer)
624→
625→ elif isinstance(node, SwitchStatement):
626→ self._compile_expression(node.discriminant)
627→
628→ jump_to_body: List[Tuple[int, int]] = []
629→ default_jump = None
630→
631→ # Compile case tests
632→ for i, case in enumerate(node.cases):
633→ if case.test:
634→ self._emit(OpCode.DUP)
635→ self._compile_expression(case.test)
636→ self._emit(OpCode.SEQ)
637→ pos = self._emit_jump(OpCode.JUMP_IF_TRUE)
638→ jump_to_body.append((pos, i))
639→ else:
640→ default_jump = (self._emit_jump(OpCode.JUMP), i)
641→
642→ # Jump to end if no match
643→ jump_end = self._emit_jump(OpCode.JUMP)
644→
645→ # Case bodies
646→ case_positions = []
647→ loop_ctx = LoopContext(is_loop=False) # For break statements only
648→ self.loop_stack.append(loop_ctx)
649→
650→ for i, case in enumerate(node.cases):
651→ case_positions.append(len(self.bytecode))
652→ for stmt in case.consequent:
653→ self._compile_statement(stmt)
654→
655→ self._patch_jump(jump_end)
656→ self._emit(OpCode.POP) # Pop discriminant
657→
658→ # Patch jumps to case bodies
659→ for pos, idx in jump_to_body:
660→ self._patch_jump(pos, case_positions[idx])
661→ if default_jump:
662→ pos, idx = default_jump
663→ self._patch_jump(pos, case_positions[idx])
664→
665→ # Patch break jumps
666→ for pos in loop_ctx.break_jumps:
667→ self._patch_jump(pos)
668→
669→ self.loop_stack.pop()
670→
671→ elif isinstance(node, FunctionDeclaration):
672→ # Compile function
673→ func = self._compile_function(node.id.name, node.params, node.body)
674→ func_idx = len(self.functions)
675→ self.functions.append(func)
676→
677→ const_idx = self._add_constant(func)
678→ self._emit(OpCode.LOAD_CONST, const_idx)
679→ self._emit(OpCode.MAKE_CLOSURE, func_idx)
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see - the finally block is just compiled after the try-catch, so it runs regardless. But the issue is that when a break happens inside the try block, it jumps directly to the break target, skipping the finally block completely.
The problem is that: 1. break/continue/return inside a try block need to run the finally block first 2. The current implementation doesn't handle this
I need to: 1. Track when we're inside a try-finally block 2. When compiling a break/continue/return inside a try block, insert code to execute the finally block first
Let me look at how break is compiled:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 50,
"offset": 540
} 540→ for pos in loop_ctx.break_jumps:
541→ self._patch_jump(pos)
542→ for pos in loop_ctx.continue_jumps:
543→ self._patch_jump(pos, loop_start)
544→
545→ self.loop_stack.pop()
546→
547→ elif isinstance(node, BreakStatement):
548→ if not self.loop_stack:
549→ raise SyntaxError("'break' outside of loop")
550→
551→ # Find the right loop context (labeled or innermost)
552→ target_label = node.label.name if node.label else None
553→ ctx = None
554→ for loop_ctx in reversed(self.loop_stack):
555→ if target_label is None or loop_ctx.label == target_label:
556→ ctx = loop_ctx
557→ break
558→
559→ if ctx is None:
560→ raise SyntaxError(f"label '{target_label}' not found")
561→
562→ pos = self._emit_jump(OpCode.JUMP)
563→ ctx.break_jumps.append(pos)
564→
565→ elif isinstance(node, ContinueStatement):
566→ if not self.loop_stack:
567→ raise SyntaxError("'continue' outside of loop")
568→
569→ # Find the right loop context (labeled or innermost loop, not switch)
570→ target_label = node.label.name if node.label else None
571→ ctx = None
572→ for loop_ctx in reversed(self.loop_stack):
573→ # Skip non-loop contexts (like switch) unless specifically labeled
574→ if not loop_ctx.is_loop and target_label is None:
575→ continue
576→ if target_label is None or loop_ctx.label == target_label:
577→ ctx = loop_ctx
578→ break
579→
580→ if ctx is None:
581→ raise SyntaxError(f"label '{target_label}' not found")
582→
583→ pos = self._emit_jump(OpCode.JUMP)
584→ ctx.continue_jumps.append(pos)
585→
586→ elif isinstance(node, ReturnStatement):
587→ if node.argument:
588→ self._compile_expression(node.argument)
589→ self._emit(OpCode.RETURN)
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see. The break just emits a JUMP that gets patched later to jump to after the loop. But if break is inside a try-finally, we need to:
The tricky part is that finally blocks can be nested, and break/continue/return should run all finally blocks between the current position and the target.
There are several approaches: 1. Inline finally blocks: When compiling break/continue/return inside a try-finally, inline the finally block code before the jump 2. Special opcode: Have a "pending finally" stack and a special opcode to run finally blocks 3. Exception-based: Throw a special "break" exception that catches and runs finally blocks
The simplest approach for this implementation is probably to: 1. Track try-finally blocks in a stack (similar to loop_stack) 2. When compiling break/continue/return, compile all pending finally blocks inline
Let me look at how the TryStatement is structured:
I need to track try-finally blocks and inline the finally code before break/continue/return. Let me look at the current TryStack implementation:
{
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"pattern": "try_stack|TryContext|finally"
}There's no try_stack yet. I need to add one. Let me look at the LoopContext class definition and create a similar TryContext:
{
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"pattern": "class LoopContext|loop_stack"
}37:class LoopContext: 53: self.loop_stack: List[LoopContext] = [] 346: self.loop_stack.append(loop_ctx) 365: self.loop_stack.pop() 369: self.loop_stack.append(loop_ctx) 386: self.loop_stack.pop() 390: self.loop_stack.append(loop_ctx) 428: self.loop_stack.pop() 432: self.loop_stack.append(loop_ctx) 495: self.loop_stack.pop() 499: self.loop_stack.append(loop_ctx) 545: self.loop_stack.pop() 548: if not self.loop_stack: 554: for loop_ctx in reversed(self.loop_stack): 566: if not self.loop_stack: 572: for loop_ctx in reversed(self.loop_stack): 648: self.loop_stack.append(loop_ctx) 669: self.loop_stack.pop() 702: self.loop_stack.append(loop_ctx) 711: self.loop_stack.pop() 815: old_loop_stack = self.loop_stack 828: self.loop_stack = [] 874: self.loop_stack = old_loop_stack 897: old_loop_stack = self.loop_stack 917: self.loop_stack = [] 969: self.loop_stack = old_loop_stack
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 40,
"offset": 35
} 35→
36→@dataclass
37→class LoopContext:
38→ """Context for loops (for break/continue)."""
39→ break_jumps: List[int] = field(default_factory=list)
40→ continue_jumps: List[int] = field(default_factory=list)
41→ label: Optional[str] = None
42→ is_loop: bool = True # False for switch statements (break only, no continue)
43→
44→
45→class Compiler:
46→ """Compiles AST to bytecode."""
47→
48→ def __init__(self):
49→ self.bytecode: List[int] = []
50→ self.constants: List[Any] = []
51→ self.names: List[str] = []
52→ self.locals: List[str] = []
53→ self.loop_stack: List[LoopContext] = []
54→ self.functions: List[CompiledFunction] = []
55→ self._in_function: bool = False # Track if we're compiling inside a function
56→ self._outer_locals: List[List[str]] = [] # Stack of outer scope locals
57→ self._free_vars: List[str] = [] # Free variables captured from outer scopes
58→ self._cell_vars: List[str] = [] # Local variables captured by inner functions
59→
60→ def compile(self, node: Program) -> CompiledFunction:
61→ """Compile a program to bytecode."""
62→ body = node.body
63→
64→ # Compile all statements except the last one
65→ for stmt in body[:-1] if body else []:
66→ self._compile_statement(stmt)
67→
68→ # For the last statement, compile with completion value semantics
69→ if body:
70→ self._compile_statement_for_value(body[-1])
71→ self._emit(OpCode.RETURN)
72→ else:
73→ # Empty program returns undefined
74→ self._emit(OpCode.LOAD_UNDEFINED)
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I need to add a try_stack to track try-finally blocks. When I compile break/continue/return inside a try-finally, I need to inline the finally code.
The issue is complex because: 1. We need to track finally blocks 2. When break/continue/return happens, we need to emit the finally block code BEFORE the jump 3. Finally blocks can be nested, so we need to run all pending finally blocks
The cleanest approach is: 1. Add a TryContext class to track finally blocks 2. When entering a try-finally block, push the finalizer AST node to a try_stack 3. When compiling break/continue/return, inline all pending finally blocks first 4. Pop from try_stack when exiting the try-finally block
Let me implement this:
@dataclass
class LoopContext:
"""Context for loops (for break/continue)."""
break_jumps: List[int] = field(default_factory=list)
continue_jumps: List[int] = field(default_factory=list)
label: Optional[str] = None
is_loop: bool = True # False for switch statements (break only, no continue)@dataclass
class LoopContext:
"""Context for loops (for break/continue)."""
break_jumps: List[int] = field(default_factory=list)
continue_jumps: List[int] = field(default_factory=list)
label: Optional[str] = None
is_loop: bool = True # False for switch statements (break only, no continue)
@dataclass
class TryContext:
"""Context for try-finally blocks (for break/continue/return)."""
finalizer: Any = None # The finally block AST nodeThe file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
32→ free_vars: List[str] = field(default_factory=list) # Variables captured from outer scope
33→ cell_vars: List[str] = field(default_factory=list) # Local variables that are captured by inner functions
34→
35→
36→@dataclass
37→class LoopContext:
38→ """Context for loops (for break/continue)."""
39→ break_jumps: List[int] = field(default_factory=list)
40→ continue_jumps: List[int] = field(default_factory=list)
41→ label: Optional[str] = None
42→ is_loop: bool = True # False for switch statements (break only, no continue)
43→
44→
45→@dataclass
46→class TryContext:
47→ """Context for try-finally blocks (for break/continue/return)."""
48→ finalizer: Any = None # The finally block AST node
49→
50→
51→class Compiler:
52→ """Compiles AST to bytecode."""Now I need to: 1. Add try_stack to the Compiler init method 2. Push/pop TryContext when compiling try-finally blocks 3. Inline finally blocks when compiling break/continue/return
Let me add try_stack to init:
self.bytecode: List[int] = []
self.constants: List[Any] = []
self.names: List[str] = []
self.locals: List[str] = []
self.loop_stack: List[LoopContext] = []
self.functions: List[CompiledFunction] = []
self._in_function: bool = False # Track if we're compiling inside a function
self._outer_locals: List[List[str]] = [] # Stack of outer scope locals
self._free_vars: List[str] = [] # Free variables captured from outer scopes
self._cell_vars: List[str] = [] # Local variables captured by inner functions self.bytecode: List[int] = []
self.constants: List[Any] = []
self.names: List[str] = []
self.locals: List[str] = []
self.loop_stack: List[LoopContext] = []
self.try_stack: List[TryContext] = [] # Track try-finally for break/continue/return
self.functions: List[CompiledFunction] = []
self._in_function: bool = False # Track if we're compiling inside a function
self._outer_locals: List[List[str]] = [] # Stack of outer scope locals
self._free_vars: List[str] = [] # Free variables captured from outer scopes
self._cell_vars: List[str] = [] # Local variables captured by inner functionsThe file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
51→class Compiler:
52→ """Compiles AST to bytecode."""
53→
54→ def __init__(self):
55→ self.bytecode: List[int] = []
56→ self.constants: List[Any] = []
57→ self.names: List[str] = []
58→ self.locals: List[str] = []
59→ self.loop_stack: List[LoopContext] = []
60→ self.try_stack: List[TryContext] = [] # Track try-finally for break/continue/return
61→ self.functions: List[CompiledFunction] = []
62→ self._in_function: bool = False # Track if we're compiling inside a function
63→ self._outer_locals: List[List[str]] = [] # Stack of outer scope locals
64→ self._free_vars: List[str] = [] # Free variables captured from outer scopes
65→ self._cell_vars: List[str] = [] # Local variables captured by inner functions
66→
67→ def compile(self, node: Program) -> CompiledFunction:
68→ """Compile a program to bytecode."""
69→ body = node.bodyNow I need to modify the TryStatement compilation to push/pop TryContext, and modify break/continue/return to inline finally blocks.
First, let me read the TryStatement compilation code:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 40,
"offset": 596
}596→ self._emit(OpCode.RETURN) 597→ else: 598→ self._emit(OpCode.RETURN_UNDEFINED) 599→ 600→ elif isinstance(node, ThrowStatement): 601→ self._compile_expression(node.argument) 602→ self._emit(OpCode.THROW) 603→ 604→ elif isinstance(node, TryStatement): 605→ # Try block 606→ try_start = self._emit_jump(OpCode.TRY_START) 607→ 608→ self._compile_statement(node.block) 609→ self._emit(OpCode.TRY_END) 610→ 611→ # Jump past catch/finally 612→ jump_end = self._emit_jump(OpCode.JUMP) 613→ 614→ # Catch handler 615→ self._patch_jump(try_start) 616→ if node.handler: 617→ self._emit(OpCode.CATCH) 618→ # Store exception in catch variable 619→ name = node.handler.param.name 620→ self._add_local(name) 621→ slot = self._get_local(name) 622→ self._emit(OpCode.STORE_LOCAL, slot) 623→ self._emit(OpCode.POP) 624→ self._compile_statement(node.handler.body) 625→ 626→ self._patch_jump(jump_end) 627→ 628→ # Finally block 629→ if node.finalizer: 630→ self._compile_statement(node.finalizer) 631→ 632→ elif isinstance(node, SwitchStatement): 633→ self._compile_expression(node.discriminant) 634→ 635→ jump_to_body: List[Tuple[int, int]] = [] <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
I see the issue. The try-catch-finally code flow is:1. TRY_START (jump to catch handler if exception) 2. Compile try block 3. TRY_END 4. JUMP to end 5. Catch handler (at TRY_START jump target) 6. Patch JUMP to end 7. Compile finally block
But the finally block should be executed: 1. After normal try block completion ✓ (currently works) 2. After catch block ✓ (currently works if we add it after catch) 3. After break/continue/return from within try ✗ (broken) 4. After exception propagation from catch ✗ (need to check)
For the break case, I need to:1. Track the finally block when entering try-finally 2. When compiling break (inside a try-finally), emit the finally code BEFORE the jump
The tricky part is that finally needs to run in both normal and abnormal (exception) cases. Let me restructure the TryStatement compilation:
elif isinstance(node, TryStatement):
# Try block
try_start = self._emit_jump(OpCode.TRY_START)
self._compile_statement(node.block)
self._emit(OpCode.TRY_END)
# Jump past catch/finally
jump_end = self._emit_jump(OpCode.JUMP)
# Catch handler
self._patch_jump(try_start)
if node.handler:
self._emit(OpCode.CATCH)
# Store exception in catch variable
name = node.handler.param.name
self._add_local(name)
slot = self._get_local(name)
self._emit(OpCode.STORE_LOCAL, slot)
self._emit(OpCode.POP)
self._compile_statement(node.handler.body)
self._patch_jump(jump_end)
# Finally block
if node.finalizer:
self._compile_statement(node.finalizer) elif isinstance(node, TryStatement):
# Push TryContext if there's a finally block so break/continue/return
# can inline the finally code
if node.finalizer:
self.try_stack.append(TryContext(finalizer=node.finalizer))
# Try block
try_start = self._emit_jump(OpCode.TRY_START)
self._compile_statement(node.block)
self._emit(OpCode.TRY_END)
# Jump past catch/finally
jump_end = self._emit_jump(OpCode.JUMP)
# Catch handler
self._patch_jump(try_start)
if node.handler:
self._emit(OpCode.CATCH)
# Store exception in catch variable
name = node.handler.param.name
self._add_local(name)
slot = self._get_local(name)
self._emit(OpCode.STORE_LOCAL, slot)
self._emit(OpCode.POP)
self._compile_statement(node.handler.body)
self._patch_jump(jump_end)
# Pop TryContext before compiling finally (break in finally shouldn't re-run finally)
if node.finalizer:
self.try_stack.pop()
# Finally block
if node.finalizer:
self._compile_statement(node.finalizer)The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 600→ elif isinstance(node, ThrowStatement): 601→ self._compile_expression(node.argument) 602→ self._emit(OpCode.THROW) 603→ 604→ elif isinstance(node, TryStatement): 605→ # Push TryContext if there's a finally block so break/continue/return 606→ # can inline the finally code 607→ if node.finalizer: 608→ self.try_stack.append(TryContext(finalizer=node.finalizer)) 609→ 610→ # Try block 611→ try_start = self._emit_jump(OpCode.TRY_START) 612→ 613→ self._compile_statement(node.block) 614→ self._emit(OpCode.TRY_END) 615→ 616→ # Jump past catch/finally 617→ jump_end = self._emit_jump(OpCode.JUMP) 618→ 619→ # Catch handler 620→ self._patch_jump(try_start) 621→ if node.handler: 622→ self._emit(OpCode.CATCH) 623→ # Store exception in catch variable 624→ name = node.handler.param.name 625→ self._add_local(name) 626→ slot = self._get_local(name) 627→ self._emit(OpCode.STORE_LOCAL, slot) 628→ self._emit(OpCode.POP) 629→ self._compile_statement(node.handler.body) 630→ 631→ self._patch_jump(jump_end) 632→ 633→ # Pop TryContext before compiling finally (break in finally shouldn't re-run finally) 634→ if node.finalizer: 635→ self.try_stack.pop() 636→ 637→ # Finally block 638→ if node.finalizer: 639→ self._compile_statement(node.finalizer) 640→ 641→ elif isinstance(node, SwitchStatement): 642→ self._compile_expression(node.discriminant) 643→
Now I need to modify break/continue/return to inline the finally blocks. Let me find the BreakStatement compilation code and add the finally inlining:
Now let me add a helper method to emit pending finally blocks, and use it in break/continue/return:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 50,
"offset": 550
} 550→ self._patch_jump(pos, loop_start)
551→
552→ self.loop_stack.pop()
553→
554→ elif isinstance(node, BreakStatement):
555→ if not self.loop_stack:
556→ raise SyntaxError("'break' outside of loop")
557→
558→ # Find the right loop context (labeled or innermost)
559→ target_label = node.label.name if node.label else None
560→ ctx = None
561→ for loop_ctx in reversed(self.loop_stack):
562→ if target_label is None or loop_ctx.label == target_label:
563→ ctx = loop_ctx
564→ break
565→
566→ if ctx is None:
567→ raise SyntaxError(f"label '{target_label}' not found")
568→
569→ pos = self._emit_jump(OpCode.JUMP)
570→ ctx.break_jumps.append(pos)
571→
572→ elif isinstance(node, ContinueStatement):
573→ if not self.loop_stack:
574→ raise SyntaxError("'continue' outside of loop")
575→
576→ # Find the right loop context (labeled or innermost loop, not switch)
577→ target_label = node.label.name if node.label else None
578→ ctx = None
579→ for loop_ctx in reversed(self.loop_stack):
580→ # Skip non-loop contexts (like switch) unless specifically labeled
581→ if not loop_ctx.is_loop and target_label is None:
582→ continue
583→ if target_label is None or loop_ctx.label == target_label:
584→ ctx = loop_ctx
585→ break
586→
587→ if ctx is None:
588→ raise SyntaxError(f"label '{target_label}' not found")
589→
590→ pos = self._emit_jump(OpCode.JUMP)
591→ ctx.continue_jumps.append(pos)
592→
593→ elif isinstance(node, ReturnStatement):
594→ if node.argument:
595→ self._compile_expression(node.argument)
596→ self._emit(OpCode.RETURN)
597→ else:
598→ self._emit(OpCode.RETURN_UNDEFINED)
599→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I need to add a helper method to emit pending finally blocks. Let me find a good place to add it and then modify break/continue/return.First, let me add a helper method that compiles all pending finally blocks:
elif isinstance(node, BreakStatement):
if not self.loop_stack:
raise SyntaxError("'break' outside of loop")
# Find the right loop context (labeled or innermost)
target_label = node.label.name if node.label else None
ctx = None
for loop_ctx in reversed(self.loop_stack):
if target_label is None or loop_ctx.label == target_label:
ctx = loop_ctx
break
if ctx is None:
raise SyntaxError(f"label '{target_label}' not found")
pos = self._emit_jump(OpCode.JUMP)
ctx.break_jumps.append(pos)
elif isinstance(node, ContinueStatement):
if not self.loop_stack:
raise SyntaxError("'continue' outside of loop")
# Find the right loop context (labeled or innermost loop, not switch)
target_label = node.label.name if node.label else None
ctx = None
for loop_ctx in reversed(self.loop_stack):
# Skip non-loop contexts (like switch) unless specifically labeled
if not loop_ctx.is_loop and target_label is None:
continue
if target_label is None or loop_ctx.label == target_label:
ctx = loop_ctx
break
if ctx is None:
raise SyntaxError(f"label '{target_label}' not found")
pos = self._emit_jump(OpCode.JUMP)
ctx.continue_jumps.append(pos)
elif isinstance(node, ReturnStatement):
if node.argument:
self._compile_expression(node.argument)
self._emit(OpCode.RETURN)
else:
self._emit(OpCode.RETURN_UNDEFINED) elif isinstance(node, BreakStatement):
if not self.loop_stack:
raise SyntaxError("'break' outside of loop")
# Find the right loop context (labeled or innermost)
target_label = node.label.name if node.label else None
ctx = None
for loop_ctx in reversed(self.loop_stack):
if target_label is None or loop_ctx.label == target_label:
ctx = loop_ctx
break
if ctx is None:
raise SyntaxError(f"label '{target_label}' not found")
# Emit pending finally blocks before the break
self._emit_pending_finally_blocks()
pos = self._emit_jump(OpCode.JUMP)
ctx.break_jumps.append(pos)
elif isinstance(node, ContinueStatement):
if not self.loop_stack:
raise SyntaxError("'continue' outside of loop")
# Find the right loop context (labeled or innermost loop, not switch)
target_label = node.label.name if node.label else None
ctx = None
for loop_ctx in reversed(self.loop_stack):
# Skip non-loop contexts (like switch) unless specifically labeled
if not loop_ctx.is_loop and target_label is None:
continue
if target_label is None or loop_ctx.label == target_label:
ctx = loop_ctx
break
if ctx is None:
raise SyntaxError(f"label '{target_label}' not found")
# Emit pending finally blocks before the continue
self._emit_pending_finally_blocks()
pos = self._emit_jump(OpCode.JUMP)
ctx.continue_jumps.append(pos)
elif isinstance(node, ReturnStatement):
# Emit pending finally blocks before the return
self._emit_pending_finally_blocks()
if node.argument:
self._compile_expression(node.argument)
self._emit(OpCode.RETURN)
else:
self._emit(OpCode.RETURN_UNDEFINED)The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
550→ self._patch_jump(pos, loop_start)
551→
552→ self.loop_stack.pop()
553→
554→ elif isinstance(node, BreakStatement):
555→ if not self.loop_stack:
556→ raise SyntaxError("'break' outside of loop")
557→
558→ # Find the right loop context (labeled or innermost)
559→ target_label = node.label.name if node.label else None
560→ ctx = None
561→ for loop_ctx in reversed(self.loop_stack):
562→ if target_label is None or loop_ctx.label == target_label:
563→ ctx = loop_ctx
564→ break
565→
566→ if ctx is None:
567→ raise SyntaxError(f"label '{target_label}' not found")
568→
569→ # Emit pending finally blocks before the break
570→ self._emit_pending_finally_blocks()
571→
572→ pos = self._emit_jump(OpCode.JUMP)
573→ ctx.break_jumps.append(pos)
574→
575→ elif isinstance(node, ContinueStatement):
576→ if not self.loop_stack:
577→ raise SyntaxError("'continue' outside of loop")
578→
579→ # Find the right loop context (labeled or innermost loop, not switch)
580→ target_label = node.label.name if node.label else None
581→ ctx = None
582→ for loop_ctx in reversed(self.loop_stack):
583→ # Skip non-loop contexts (like switch) unless specifically labeled
584→ if not loop_ctx.is_loop and target_label is None:
585→ continue
586→ if target_label is None or loop_ctx.label == target_label:
587→ ctx = loop_ctx
588→ break
589→
590→ if ctx is None:
591→ raise SyntaxError(f"label '{target_label}' not found")
592→
593→ # Emit pending finally blocks before the continue
594→ self._emit_pending_finally_blocks()
595→
596→ pos = self._emit_jump(OpCode.JUMP)
597→ ctx.continue_jumps.append(pos)
598→
599→ elif isinstance(node, ReturnStatement):
600→ # Emit pending finally blocks before the return
601→ self._emit_pending_finally_blocks()
602→
603→ if node.argument:
604→ self._compile_expression(node.argument)
605→ self._emit(OpCode.RETURN)
606→ else:
607→ self._emit(OpCode.RETURN_UNDEFINED)
608→
609→ elif isinstance(node, ThrowStatement):
610→ self._compile_expression(node.argument)
611→ self._emit(OpCode.THROW)Now I need to add the _emit_pending_finally_blocks method. Let me find a good place to add it, near other helper methods:
{
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"pattern": "def _emit_jump|def _patch_jump|def _emit"
}96: def _emit(self, opcode: OpCode, arg: Optional[int] = None) -> int: 109: def _emit_jump(self, opcode: OpCode) -> int: 120: def _patch_jump(self, pos: int, target: Optional[int] = None) -> None:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 30,
"offset": 116
}116→ self.bytecode.append(0) # Low byte placeholder 117→ self.bytecode.append(0) # High byte placeholder 118→ return pos 119→ 120→ def _patch_jump(self, pos: int, target: Optional[int] = None) -> None: 121→ """Patch a jump instruction to jump to target (or current position). 122→ 123→ Uses 16-bit (2 byte) little-endian offset. 124→ """ 125→ if target is None: 126→ target = len(self.bytecode) 127→ self.bytecode[pos + 1] = target & 0xFF # Low byte 128→ self.bytecode[pos + 2] = (target >> 8) & 0xFF # High byte 129→ 130→ def _add_constant(self, value: Any) -> int: 131→ """Add a constant and return its index.""" 132→ if value in self.constants: 133→ return self.constants.index(value) 134→ self.constants.append(value) 135→ return len(self.constants) - 1 136→ 137→ def _add_name(self, name: str) -> int: 138→ """Add a name and return its index (stored in constants).""" 139→ # Store names in constants so VM can look them up 140→ return self._add_constant(name) 141→ 142→ def _add_local(self, name: str) -> int: 143→ """Add a local variable and return its slot.""" 144→ if name in self.locals: 145→ return self.locals.index(name) <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
def _patch_jump(self, pos: int, target: Optional[int] = None) -> None:
"""Patch a jump instruction to jump to target (or current position).
Uses 16-bit (2 byte) little-endian offset.
"""
if target is None:
target = len(self.bytecode)
self.bytecode[pos + 1] = target & 0xFF # Low byte
self.bytecode[pos + 2] = (target >> 8) & 0xFF # High byte
def _add_constant(self, value: Any) -> int: def _patch_jump(self, pos: int, target: Optional[int] = None) -> None:
"""Patch a jump instruction to jump to target (or current position).
Uses 16-bit (2 byte) little-endian offset.
"""
if target is None:
target = len(self.bytecode)
self.bytecode[pos + 1] = target & 0xFF # Low byte
self.bytecode[pos + 2] = (target >> 8) & 0xFF # High byte
def _emit_pending_finally_blocks(self) -> None:
"""Emit all pending finally blocks (for break/continue/return)."""
# Emit finally blocks in reverse order (innermost first)
for try_ctx in reversed(self.try_stack):
if try_ctx.finalizer:
self._compile_statement(try_ctx.finalizer)
def _add_constant(self, value: Any) -> int:The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 116→ self.bytecode.append(0) # Low byte placeholder 117→ self.bytecode.append(0) # High byte placeholder 118→ return pos 119→ 120→ def _patch_jump(self, pos: int, target: Optional[int] = None) -> None: 121→ """Patch a jump instruction to jump to target (or current position). 122→ 123→ Uses 16-bit (2 byte) little-endian offset. 124→ """ 125→ if target is None: 126→ target = len(self.bytecode) 127→ self.bytecode[pos + 1] = target & 0xFF # Low byte 128→ self.bytecode[pos + 2] = (target >> 8) & 0xFF # High byte 129→ 130→ def _emit_pending_finally_blocks(self) -> None: 131→ """Emit all pending finally blocks (for break/continue/return).""" 132→ # Emit finally blocks in reverse order (innermost first) 133→ for try_ctx in reversed(self.try_stack): 134→ if try_ctx.finalizer: 135→ self._compile_statement(try_ctx.finalizer) 136→ 137→ def _add_constant(self, value: Any) -> int: 138→ """Add a constant and return its index.""" 139→ if value in self.constants: 140→ return self.constants.index(value) 141→ self.constants.append(value)
uv run pytest tests/test_vm.py::TestTryFinallyBreak -v 2>&1
============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python cachedir: .pytest_cache rootdir: /home/user/mquickjs-python configfile: pyproject.toml collecting ... collected 1 item tests/test_vm.py::TestTryFinallyBreak::test_break_in_try_finally PASSED [100%] ============================== 1 passed in 0.07s ===============================
The test passes. Now let me run the full test_loop.js to see if all try-catch tests pass:
timeout 15 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
ctx.eval(open('tests/test_loop.js').read())
print('All test_loop.js tests passed!')
" 2>&1Exit code 1
Traceback (most recent call last):
File "<string>", line 4, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 603, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 106, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 163, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 514, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1652, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got |tfgundefinedg|, expected |tfag| (catch)There's an issue with test_try_catch7. Let me check what that test does:javascriptfunction test_try_catch7(){
var s; s = "";
try { try {
s += "t";
throw "a";
} finally {
s += "f";
}
} catch(e) { s += e;
} finally {
s += "g";
} assert(s, "tfag", "catch");}Expected: "tfag"Got: "tfgundefinedg"
So the flow should be:1. s += "t" → "t"2. throw "a" 3. Inner finally: s += "f" → "tf" 4. Exception propagates to outer catch 5. Outer catch: s += e (which is "a") → "tfa" 6. Outer finally: s += "g" → "tfag"But we're getting "tfgundefinedg", which suggests:1. s += "t" → "t"2. throw "a" 3. Inner finally: s += "f" → "tf" 4. Outer finally runs incorrectly? s += "g" → "tfg" 5. Then something weird with "undefined" 6. Outer finally again: s += "g" → "tfgundefinedg"
The issue is that the throw is triggering the finally block before the exception handler, but then continuing incorrectly. The problem is complex - when an exception is thrown inside a try block, the finally should run but the exception should still propagate.Actually, looking more carefully, the issue is that I'm adding TRY_END before the jump, but when a throw happens, the exception handler in the VM pops the try context. But my compiler is pushing/popping TryContext at compile time, not at runtime.
The issue is that my fix works for break/continue/return, but for throw (exception), the finally should run via the runtime exception handling mechanism, not via compile-time inlining.
I'm investigating the nuanced behavior of exception handling and finally blocks. The current compilation strategy differs for various control flow mechanisms. Specifically, the runtime exception handling requires a different approach compared to compile-time inlining used for other control flow statements. The VM's exception mechanism needs special consideration to ensure proper finally block execution while maintaining exception propagation.
The core challenge involves ensuring the finally block runs consistently - whether an exception occurs or normal completion happens. My proposed solution involves modifying the VM's exception handling logic to intercept exceptions at the TRY_START point and explicitly execute the finally block before either rethrowing or continuing to catch processing.
The implementation needs to guarantee that the finally block becomes a mandatory step in the exception handling sequence, preventing scenarios where it might be skipped or improperly executed.
By carefully tracing the test case, I can see a critical gap in the current exception propagation mechanism where exceptions can get lost or mishandled when no explicit catch handler exists.
The inner try-finally block seems to have an incomplete exception handling strategy. When an exception is thrown, the finally block runs, but the exception appears to vanish instead of being re-thrown to the outer exception handler. This suggests a potential flaw in how the virtual machine manages exception contexts and propagation.
The key observation is that without a specific CATCH opcode, the exception might not be correctly passed up the call stack, effectively suppressing the original error condition.
There's an issue with try-finally when exceptions are thrown. Let me check the VM's exception handling:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 50,
"offset": 510
}510→ 511→ # Exception handling 512→ elif op == OpCode.THROW: 513→ exc = self.stack.pop() 514→ self._throw(exc) 515→ 516→ elif op == OpCode.TRY_START: 517→ # arg is the catch handler offset 518→ self.exception_handlers.append((len(self.call_stack) - 1, arg)) 519→ 520→ elif op == OpCode.TRY_END: 521→ if self.exception_handlers: 522→ self.exception_handlers.pop() 523→ 524→ elif op == OpCode.CATCH: 525→ # Exception is on stack 526→ pass 527→ 528→ # Iteration 529→ elif op == OpCode.FOR_IN_INIT: 530→ obj = self.stack.pop() 531→ if obj is UNDEFINED or obj is NULL: 532→ keys = [] 533→ elif isinstance(obj, JSArray): 534→ # For arrays, iterate over numeric indices as strings 535→ keys = [str(i) for i in range(len(obj._elements))] 536→ # Also include any non-numeric properties 537→ keys.extend(obj.keys()) 538→ elif isinstance(obj, JSObject): 539→ keys = obj.keys() 540→ else: 541→ keys = [] 542→ self.stack.append(ForInIterator(keys)) 543→ 544→ elif op == OpCode.FOR_IN_NEXT: 545→ iterator = self.stack[-1] 546→ if isinstance(iterator, ForInIterator): 547→ key, done = iterator.next() 548→ if done: 549→ self.stack.append(True) 550→ else: 551→ self.stack.append(key) 552→ self.stack.append(False) 553→ else: 554→ self.stack.append(True) 555→ 556→ elif op == OpCode.FOR_OF_INIT: 557→ iterable = self.stack.pop() 558→ if iterable is UNDEFINED or iterable is NULL: 559→ values = [] <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
{
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "def _throw"
}{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 40,
"offset": 1630
} 1630→
1631→ def _throw(self, exc: JSValue) -> None:
1632→ """Throw an exception."""
1633→ if self.exception_handlers:
1634→ frame_idx, catch_ip = self.exception_handlers.pop()
1635→
1636→ # Unwind call stack
1637→ while len(self.call_stack) > frame_idx + 1:
1638→ self.call_stack.pop()
1639→
1640→ # Jump to catch handler
1641→ frame = self.call_stack[-1]
1642→ frame.ip = catch_ip
1643→
1644→ # Push exception value
1645→ self.stack.append(exc)
1646→ else:
1647→ # Uncaught exception
1648→ if isinstance(exc, str):
1649→ raise JSError(exc)
1650→ elif isinstance(exc, JSObject):
1651→ msg = exc.get("message")
1652→ raise JSError(to_string(msg) if msg else "Error")
1653→ else:
1654→ raise JSError(to_string(exc))
1655→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see. The issue is that for try-finally (without catch), the exception handler jumps to the "catch" position, but there's no actual catch - just the finally block is there. After the finally block runs, the exception should be re-thrown.
The problem is: 1. For try-catch-finally: TRY_START target goes to CATCH opcode, catch runs, then finally runs2. For try-finally (no catch): TRY_START target goes to... where? Currently it goes right after the TRY_END/JUMP, which would be where CATCH would be, but there's no CATCH.
Looking at my compiler code:```python try_start = self._emit_jump(OpCode.TRY_START) self._compile_statement(node.block) self._emit(OpCode.TRY_END) jump_end = self._emit_jump(OpCode.JUMP)
self._patch_jump(try_start) # TRY_START target = here if node.handler: self._emit(OpCode.CATCH) ...
self._patch_jump(jump_end)
if node.finalizer: self._compile_statement(node.finalizer) ```
For try-finally (no catch):- TRY_START target points right after JUMP- If exception occurs, it jumps there - There's no CATCH opcode, so the exception stays on stack - Then JUMP is patched to skip to after finally... wait, no. The jump_end is patched to the current position, which is before the finally block.Actually, let me trace this more carefully for try-finally:1. TRY_START (target = after JUMP opcode) 2. Compile try block 3. TRY_END4. JUMP to ??? 5. (TRY_START target is here) 6. (no CATCH)7.
I realize the patch_jump(jump_end) operation creates a problematic flow. When an exception occurs, it jumps to a position with no code, then falls through to the finally block. The critical issue is that the exception remains on the stack and is never re-thrown, breaking the expected exception handling semantics for try-finally blocks.
I need a mechanism to ensure exceptions are properly propagated after the finally block completes. This requires either adding a special rethrow opcode or implementing a catch handler that immediately re-throws the exception. The goal is to maintain the expected behavior where exceptions are preserved and re-raised after executing the cleanup code.
The core requirement is to modify the compiler's exception handling logic to explicitly handle the re-throwing of exceptions in try-finally scenarios, ensuring the original exception is not silently swallowed.
I'll design an approach that minimizes code duplication while guaranteeing correct exception semantics. The solution involves creating a mechanism that tracks the exception state and enables controlled re-throwing after the final block executes.
The control flow strategy involves marking exception paths, executing the finally block in both normal and exceptional scenarios, and ensuring exceptions propagate correctly. By using specific opcodes like TRY_START, TRY_END, and strategic JUMP instructions, we can manage complex exception handling scenarios without unnecessary code repetition.
The key is creating a clean mechanism where the finally block always executes, whether an exception occurs or not, while preserving the original exception's trajectory through the execution stack.
I see the issue. For try-finally without catch, the exception needs to be rethrown after finally. Let me fix the compiler:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 50,
"offset": 612
}612→ self._emit(OpCode.RETURN) 613→ else: 614→ self._emit(OpCode.RETURN_UNDEFINED) 615→ 616→ elif isinstance(node, ThrowStatement): 617→ self._compile_expression(node.argument) 618→ self._emit(OpCode.THROW) 619→ 620→ elif isinstance(node, TryStatement): 621→ # Push TryContext if there's a finally block so break/continue/return 622→ # can inline the finally code 623→ if node.finalizer: 624→ self.try_stack.append(TryContext(finalizer=node.finalizer)) 625→ 626→ # Try block 627→ try_start = self._emit_jump(OpCode.TRY_START) 628→ 629→ self._compile_statement(node.block) 630→ self._emit(OpCode.TRY_END) 631→ 632→ # Jump past catch/finally 633→ jump_end = self._emit_jump(OpCode.JUMP) 634→ 635→ # Catch handler 636→ self._patch_jump(try_start) 637→ if node.handler: 638→ self._emit(OpCode.CATCH) 639→ # Store exception in catch variable 640→ name = node.handler.param.name 641→ self._add_local(name) 642→ slot = self._get_local(name) 643→ self._emit(OpCode.STORE_LOCAL, slot) 644→ self._emit(OpCode.POP) 645→ self._compile_statement(node.handler.body) 646→ 647→ self._patch_jump(jump_end) 648→ 649→ # Pop TryContext before compiling finally (break in finally shouldn't re-run finally) 650→ if node.finalizer: 651→ self.try_stack.pop() 652→ 653→ # Finally block 654→ if node.finalizer: 655→ self._compile_statement(node.finalizer) 656→ 657→ elif isinstance(node, SwitchStatement): 658→ self._compile_expression(node.discriminant) 659→ 660→ jump_to_body: List[Tuple[int, int]] = [] 661→ default_jump = None <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
I need to fix the try-finally compilation. For try-finally without catch, after the finally block runs in the exception path, the exception needs to be rethrown.
Here's my plan: 1. For try-finally (no catch), compile a different structure: - TRY_START → exception_finally - try block - TRY_END - JUMP → normal_finally - exception_finally: - exception is on stack - compile finally - THROW (rethrow exception) - normal_finally: - compile finally
Wait, there's an issue. For try-catch-finally, if an exception is thrown in the catch block, the finally should still run. So we need: - TRY_START → catch_handler - try block - TRY_END - JUMP → normal_finally - catch_handler: - [need another TRY_START for catch block too?]
This is getting complex. Let me think about a simpler approach.
Actually, maybe the cleanest is: 1. For try-finally without catch: emit finally in exception path, then THROW 2. For try-catch-finally: after catch block, jump to finally; the finally is shared
Let me implement this step by step:
elif isinstance(node, TryStatement):
# Push TryContext if there's a finally block so break/continue/return
# can inline the finally code
if node.finalizer:
self.try_stack.append(TryContext(finalizer=node.finalizer))
# Try block
try_start = self._emit_jump(OpCode.TRY_START)
self._compile_statement(node.block)
self._emit(OpCode.TRY_END)
# Jump past catch/finally
jump_end = self._emit_jump(OpCode.JUMP)
# Catch handler
self._patch_jump(try_start)
if node.handler:
self._emit(OpCode.CATCH)
# Store exception in catch variable
name = node.handler.param.name
self._add_local(name)
slot = self._get_local(name)
self._emit(OpCode.STORE_LOCAL, slot)
self._emit(OpCode.POP)
self._compile_statement(node.handler.body)
self._patch_jump(jump_end)
# Pop TryContext before compiling finally (break in finally shouldn't re-run finally)
if node.finalizer:
self.try_stack.pop()
# Finally block
if node.finalizer:
self._compile_statement(node.finalizer) elif isinstance(node, TryStatement):
# Push TryContext if there's a finally block so break/continue/return
# can inline the finally code
if node.finalizer:
self.try_stack.append(TryContext(finalizer=node.finalizer))
# Try block
try_start = self._emit_jump(OpCode.TRY_START)
self._compile_statement(node.block)
self._emit(OpCode.TRY_END)
# Jump past exception handler to normal finally
jump_to_finally = self._emit_jump(OpCode.JUMP)
# Exception handler
self._patch_jump(try_start)
if node.handler:
# Has catch block
self._emit(OpCode.CATCH)
# Store exception in catch variable
name = node.handler.param.name
self._add_local(name)
slot = self._get_local(name)
self._emit(OpCode.STORE_LOCAL, slot)
self._emit(OpCode.POP)
self._compile_statement(node.handler.body)
# Fall through to finally
elif node.finalizer:
# No catch, only finally - exception is on stack
# Run finally then rethrow
self._compile_statement(node.finalizer)
self._emit(OpCode.THROW) # Rethrow the exception
# Pop TryContext before compiling normal finally
if node.finalizer:
self.try_stack.pop()
# Normal finally block (after try completes normally or after catch)
self._patch_jump(jump_to_finally)
if node.finalizer:
self._compile_statement(node.finalizer)The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 616→ elif isinstance(node, ThrowStatement): 617→ self._compile_expression(node.argument) 618→ self._emit(OpCode.THROW) 619→ 620→ elif isinstance(node, TryStatement): 621→ # Push TryContext if there's a finally block so break/continue/return 622→ # can inline the finally code 623→ if node.finalizer: 624→ self.try_stack.append(TryContext(finalizer=node.finalizer)) 625→ 626→ # Try block 627→ try_start = self._emit_jump(OpCode.TRY_START) 628→ 629→ self._compile_statement(node.block) 630→ self._emit(OpCode.TRY_END) 631→ 632→ # Jump past exception handler to normal finally 633→ jump_to_finally = self._emit_jump(OpCode.JUMP) 634→ 635→ # Exception handler 636→ self._patch_jump(try_start) 637→ if node.handler: 638→ # Has catch block 639→ self._emit(OpCode.CATCH) 640→ # Store exception in catch variable 641→ name = node.handler.param.name 642→ self._add_local(name) 643→ slot = self._get_local(name) 644→ self._emit(OpCode.STORE_LOCAL, slot) 645→ self._emit(OpCode.POP) 646→ self._compile_statement(node.handler.body) 647→ # Fall through to finally 648→ elif node.finalizer: 649→ # No catch, only finally - exception is on stack 650→ # Run finally then rethrow 651→ self._compile_statement(node.finalizer) 652→ self._emit(OpCode.THROW) # Rethrow the exception 653→ 654→ # Pop TryContext before compiling normal finally 655→ if node.finalizer: 656→ self.try_stack.pop() 657→ 658→ # Normal finally block (after try completes normally or after catch) 659→ self._patch_jump(jump_to_finally) 660→ if node.finalizer: 661→ self._compile_statement(node.finalizer) 662→ 663→ elif isinstance(node, SwitchStatement): 664→ self._compile_expression(node.discriminant) 665→
timeout 15 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
ctx.eval(open('tests/test_loop.js').read())
print('All test_loop.js tests passed!')
" 2>&1Excellent! Now let me make sure our initial test still passes and run the full test suite:
============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 rootdir: /home/user/mquickjs-python configfile: pyproject.toml collected 389 items tests/test_arrow_functions.py ............. [ 3%] tests/test_basic.py . [ 3%] tests/test_compatibility.py ............................................ [ 14%] . [ 15%] tests/test_function_methods.py ........... [ 17%] tests/test_js_basic.py ....................xxxXxXx [ 24%] tests/test_jscontext_regexp.py .................. [ 29%] tests/test_lexer.py .................................................... [ 42%] .. [ 43%] tests/test_parser.py ................................................... [ 56%] ........ [ 58%] tests/test_regex.py .................................................... [ 71%] ......xx............................ [ 81%] tests/test_string_regex.py ................... [ 86%] tests/test_vm.py ...................................................... [100%] ================== 380 passed, 7 xfailed, 2 xpassed in 4.54s ===================
380 passed, 7 xfailed, 2 xpassed. That's even better than before. Let me commit this fix and move on to the next task.
git add -A && git commit -m "$(cat <<'EOF' Fix try-finally interaction with break/continue/return and exceptions - Add TryContext to track finally blocks at compile time - Emit pending finally blocks before break/continue/return - For try-finally without catch, run finally then rethrow exception - All test_loop.js try-catch tests now pass EOF )"
2 files changed, 63 insertions(+), 5 deletions(-)
To http://127.0.0.1:50794/git/simonw/mquickjs-python 4a56c7c..6cf3a86 claude/python-mquickjs-port-uPKcc -> claude/python-mquickjs-port-uPKcc branch 'claude/python-mquickjs-port-uPKcc' set up to track 'origin/claude/python-mquickjs-port-uPKcc'.
Todos have been modified successfully. Ensure that you continue to use the todo list to track your progress. Please proceed with the current tasks if applicable
Now let me check the remaining xfail tests to see what needs to be done for regex lookbehind:
uv run pytest tests/ --collect-only -q 2>&1 | grep -i xfail || uv run pytest tests/test_regex.py -v 2>&1 | grep -E "XFAIL|XPASS|lookbehind"
tests/test_regex.py::TestLookbehind::test_positive_lookbehind XFAIL [ 67%] tests/test_regex.py::TestLookbehind::test_negative_lookbehind XFAIL [ 68%]
tests/test_js_basic.py::test_mquickjs_js[mandelbrot.js-path0] XFAIL [ 23%] tests/test_js_basic.py::test_mquickjs_js[microbench.js-path1] XFAIL [ 23%] tests/test_js_basic.py::test_mquickjs_js[test_builtin.js-path2] XFAIL [ 23%] tests/test_js_basic.py::test_mquickjs_js[test_language.js-path4] XFAIL [ 24%] tests/test_js_basic.py::test_mquickjs_js[test_rect.js-path6] XFAIL (...) [ 24%] tests/test_regex.py::TestLookbehind::test_positive_lookbehind XFAIL [ 73%] tests/test_regex.py::TestLookbehind::test_negative_lookbehind XFAIL [ 74%] ================== 380 passed, 7 xfailed, 2 xpassed in 4.58s ===================
There are 7 xfail tests:1. mandelbrot.js - likely uses features we don't have yet 2. microbench.js - likely uses features we don't have yet3. test_builtin.js - built-in objects/functions 4. test_language.js - language features 5. test_rect.js - unknown6. test_positive_lookbehind - regex lookbehind 7. test_negative_lookbehind - regex lookbehindLet me check what the xpassed tests are (tests that were expected to fail but now pass):
tests/test_js_basic.py::test_mquickjs_js[test_closure.js-path3] XPASS [ 24%] tests/test_js_basic.py::test_mquickjs_js[test_loop.js-path5] XPASS (...) [ 24%] ================== 380 passed, 7 xfailed, 2 xpassed in 4.66s ===================
test_closure.js and test_loop.js were expected to fail but now pass - that's because of my fixes. I should update the test markers to not expect these to fail anymore. But first, let me focus on the regex lookbehind.Let me look at the lookbehind tests:
{
"-C": 5,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/tests/test_regex.py",
"pattern": "class TestLookbehind|test_positive_lookbehind|test_negative_lookbehind"
}430- re = RegExp(r"foo(?!bar)")
431- assert re.test("foobaz") is True
432- assert re.test("foobar") is False
433-
434-
435:class TestLookbehind:
436- """Test lookbehind assertions."""
437-
438- @pytest.mark.xfail(reason="Lookbehind not yet implemented")
439: def test_positive_lookbehind(self):
440- """Positive lookbehind (?<=...)."""
441- re = RegExp(r"(?<=foo)bar")
442- assert re.test("foobar") is True
443- assert re.test("bazbar") is False
444-
445- @pytest.mark.xfail(reason="Lookbehind not yet implemented")
446: def test_negative_lookbehind(self):
447- """Negative lookbehind (?<!...)."""
448- re = RegExp(r"(?<!foo)bar")
449- assert re.test("bazbar") is True
450- assert re.test("foobar") is False
451-I need to implement lookbehind assertions in the regex engine. Let me find the regex implementation:
{
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/regex.py",
"pattern": "lookahead|(?=|(?!"
}<tool_use_error>Path does not exist: /home/user/mquickjs-python/src/mquickjs_python/regex.py</tool_use_error>
/home/user/mquickjs-python/.venv/lib/python3.11/site-packages/pygments/regexopt.py /home/user/mquickjs-python/src/mquickjs_python/regex/regex.py
1→"""
2→Main regex module - public interface.
3→
4→Provides JavaScript-compatible RegExp with ReDoS protection.
5→"""
6→
7→from typing import Optional, Callable, List
8→from .parser import RegexParser, RegExpError
9→from .compiler import RegexCompiler
10→from .vm import RegexVM, MatchResult, RegexTimeoutError, RegexStackOverflow
11→
12→
13→__all__ = ['RegExp', 'RegExpError', 'match', 'search', 'test',
14→ 'RegexTimeoutError', 'RegexStackOverflow', 'MatchResult']
15→
16→
17→class RegExp:
18→ """
19→ JavaScript-compatible regular expression object.
20→
21→ Provides safe regex matching with ReDoS protection.
22→ """
23→
24→ def __init__(
25→ self,
26→ pattern: str,
27→ flags: str = "",
28→ poll_callback: Optional[Callable[[], bool]] = None,
29→ stack_limit: int = 10000,
30→ poll_interval: int = 100
31→ ):
32→ """
33→ Create a new RegExp.
34→
35→ Args:
36→ pattern: The regex pattern string
37→ flags: Optional flags (g, i, m, s, u, y)
38→ poll_callback: Called periodically; return True to abort
39→ stack_limit: Maximum backtrack stack size
40→ poll_interval: Steps between poll calls
41→ """
42→ self.source = pattern
43→ self.flags = flags
44→ self._global = 'g' in flags
45→ self._ignore_case = 'i' in flags
46→ self._multiline = 'm' in flags
47→ self._dotall = 's' in flags
48→ self._unicode = 'u' in flags
49→ self._sticky = 'y' in flags
50→ self.lastIndex = 0
51→
52→ self._poll_callback = poll_callback
53→ self._stack_limit = stack_limit
54→ self._poll_interval = poll_interval
55→
56→ # Parse and compile
57→ try:
58→ parser = RegexParser(pattern, flags)
59→ self._ast, self._capture_count = parser.parse()
60→
61→ compiler = RegexCompiler(flags)
62→ self._bytecode = compiler.compile(self._ast, self._capture_count)
63→ self._compiled = True
64→ except Exception as e:
65→ if isinstance(e, RegExpError):
66→ raise
67→ raise RegExpError(f"Failed to compile regex: {e}")
68→
69→ @property
70→ def global_(self):
71→ return self._global
72→
73→ @property
74→ def ignoreCase(self):
75→ return self._ignore_case
76→
77→ @property
78→ def multiline(self):
79→ return self._multiline
80→
81→ @property
82→ def dotAll(self):
83→ return self._dotall
84→
85→ @property
86→ def unicode(self):
87→ return self._unicode
88→
89→ @property
90→ def sticky(self):
91→ return self._sticky
92→
93→ def _create_vm(self) -> RegexVM:
94→ """Create a new VM instance."""
95→ return RegexVM(
96→ self._bytecode,
97→ self._capture_count,
98→ self.flags,
99→ self._poll_callback,
100→ self._stack_limit,
101→ self._poll_interval
102→ )
103→
104→ def test(self, string: str) -> bool:
105→ """
106→ Test if the pattern matches the string.
107→
108→ Args:
109→ string: The string to test
110→
111→ Returns:
112→ True if there's a match, False otherwise
113→ """
114→ vm = self._create_vm()
115→
116→ if self._sticky:
117→ result = vm.match(string, self.lastIndex)
118→ if result:
119→ if self._global:
120→ self.lastIndex = result.index + len(result[0]) if result[0] else result.index
121→ return True
122→ if self._global:
123→ self.lastIndex = 0
124→ return False
125→
126→ result = vm.search(string, self.lastIndex if self._global else 0)
127→ if result:
128→ if self._global:
129→ self.lastIndex = result.index + len(result[0]) if result[0] else result.index + 1
130→ return True
131→
132→ if self._global:
133→ self.lastIndex = 0
134→ return False
135→
136→ def exec(self, string: str) -> Optional[MatchResult]:
137→ """
138→ Execute a search for a match.
139→
140→ Args:
141→ string: The string to search
142→
143→ Returns:
144→ Match array or None if no match
145→ """
146→ vm = self._create_vm()
147→
148→ if self._sticky:
149→ result = vm.match(string, self.lastIndex)
150→ if result:
151→ if self._global or self._sticky:
152→ self.lastIndex = result.index + len(result[0]) if result[0] else result.index
153→ return result
154→ if self._global or self._sticky:
155→ self.lastIndex = 0
156→ return None
157→
158→ start_pos = self.lastIndex if self._global else 0
159→ result = vm.search(string, start_pos)
160→
161→ if result:
162→ if self._global:
163→ self.lastIndex = result.index + len(result[0]) if result[0] else result.index + 1
164→ return result
165→
166→ if self._global:
167→ self.lastIndex = 0
168→ return None
169→
170→
171→def match(pattern: str, string: str, flags: str = "") -> Optional[MatchResult]:
172→ """
173→ Convenience function to match pattern against string.
174→
175→ Args:
176→ pattern: The regex pattern
177→ string: The string to match
178→ flags: Optional flags
179→
180→ Returns:
181→ Match result or None
182→ """
183→ return RegExp(pattern, flags).exec(string)
184→
185→
186→def search(pattern: str, string: str, flags: str = "") -> Optional[MatchResult]:
187→ """
188→ Search for pattern in string.
189→
190→ Args:
191→ pattern: The regex pattern
192→ string: The string to search
193→ flags: Optional flags
194→
195→ Returns:
196→ Match result or None
197→ """
198→ return RegExp(pattern, flags).exec(string)
199→
200→
201→def test(pattern: str, string: str, flags: str = "") -> bool:
202→ """
203→ Test if pattern matches string.
204→
205→ Args:
206→ pattern: The regex pattern
207→ string: The string to test
208→ flags: Optional flags
209→
210→ Returns:
211→ True if matches, False otherwise
212→ """
213→ return RegExp(pattern, flags).test(string)
214→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I need to look at the parser and compiler to understand how lookahead is implemented, then add lookbehind:
/home/user/mquickjs-python/src/mquickjs_python/regex/opcodes.py /home/user/mquickjs-python/src/mquickjs_python/regex/compiler.py /home/user/mquickjs-python/src/mquickjs_python/regex/regex.py /home/user/mquickjs-python/src/mquickjs_python/regex/__init__.py /home/user/mquickjs-python/src/mquickjs_python/regex/vm.py /home/user/mquickjs-python/src/mquickjs_python/regex/parser.py
The user wants me to remove the xfail decorator from tests that now pass. Let me do that first, then continue with lookbehind.
{
"-B": 3,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/tests/test_js_basic.py",
"pattern": "test_closure|test_loop"
} 1→"""
2→Parameterized pytest tests for JavaScript files.
3→
4→- Each .js file in tests/basic/ is run as a test case (should pass)
5→- Each .js file in tests/ (original mquickjs tests) is run with xfail (expected to fail)
6→"""
7→from pathlib import Path
8→
9→import pytest
10→
11→from mquickjs_python import JSContext
12→
13→
14→def get_basic_test_files():
15→ """Discover all .js files in tests/basic/ directory."""
16→ basic_dir = Path(__file__).parent / "basic"
17→ if not basic_dir.exists():
18→ return []
19→ js_files = sorted(basic_dir.glob("*.js"))
20→ return [(f.name, f) for f in js_files]
21→
22→
23→def get_mquickjs_test_files():
24→ """Discover original mquickjs .js test files in tests/ directory."""
25→ tests_dir = Path(__file__).parent
26→ # Get all .js files directly in tests/ (not in subdirectories)
27→ js_files = sorted(tests_dir.glob("*.js"))
28→ return [(f.name, f) for f in js_files]
29→
30→
31→@pytest.mark.parametrize(
32→ "name,path",
33→ get_basic_test_files(),
34→ ids=lambda x: x if isinstance(x, str) else None,
35→)
36→def test_basic_js(name: str, path: Path):
37→ """Run a basic JavaScript test file."""
38→ source = path.read_text(encoding="utf-8")
39→ ctx = JSContext()
40→ # Execute the script - if it throws, the test fails
41→ ctx.eval(source)
42→
43→
44→@pytest.mark.parametrize(
45→ "name,path",
46→ get_mquickjs_test_files(),
47→ ids=lambda x: x if isinstance(x, str) else None,
48→)
49→@pytest.mark.xfail(reason="Original mquickjs tests - not yet passing")
50→def test_mquickjs_js(name: str, path: Path):
51→ """Run an original mquickjs JavaScript test file.
52→
53→ These tests are expected to fail until the VM is complete.
54→ Watch for xfail tests that start passing!
55→ """
56→ source = path.read_text(encoding="utf-8")
57→ ctx = JSContext(time_limit=2.0) # Timeout to avoid infinite loops
58→ # Execute the script - if it throws, the test fails
59→ ctx.eval(source)
60→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see - the xfail decorator is applied to all files in tests/*.js. The tests that pass (test_closure.js and test_loop.js) should be moved to tests/basic/ to avoid the xfail marker.
Let me move those files:
I see - tests in tests/ are xfail, tests in tests/basic/ are expected to pass. Let me move the passing tests:
/home/user/mquickjs-python/tests/mandelbrot.js /home/user/mquickjs-python/tests/microbench.js /home/user/mquickjs-python/tests/test_builtin.js /home/user/mquickjs-python/tests/test_closure.js /home/user/mquickjs-python/tests/test_language.js /home/user/mquickjs-python/tests/test_loop.js /home/user/mquickjs-python/tests/test_rect.js
mv /home/user/mquickjs-python/tests/test_closure.js /home/user/mquickjs-python/tests/basic/ && mv /home/user/mquickjs-python/tests/test_loop.js /home/user/mquickjs-python/tests/basic/
tests/test_js_basic.py::test_basic_js[test_loop_break.js-path8] PASSED [ 34%] tests/test_js_basic.py::test_basic_js[test_loop_for.js-path9] PASSED [ 38%] tests/test_js_basic.py::test_basic_js[test_loop_switch.js-path10] PASSED [ 42%] tests/test_js_basic.py::test_basic_js[test_loop_switch2.js-path11] PASSED [ 46%] tests/test_js_basic.py::test_basic_js[test_loop_try5.js-path12] PASSED [ 50%] tests/test_js_basic.py::test_basic_js[test_loop_while.js-path13] PASSED [ 53%] tests/test_js_basic.py::test_basic_js[test_math.js-path14] PASSED [ 57%] tests/test_js_basic.py::test_basic_js[test_number_date.js-path15] PASSED [ 61%] tests/test_js_basic.py::test_basic_js[test_object_methods.js-path16] PASSED [ 65%] tests/test_js_basic.py::test_basic_js[test_regexp.js-path17] PASSED [ 69%] tests/test_js_basic.py::test_basic_js[test_string_methods.js-path18] PASSED [ 73%] tests/test_js_basic.py::test_basic_js[test_try_catch.js-path19] PASSED [ 76%] tests/test_js_basic.py::test_basic_js[test_try_catch_simple.js-path20] PASSED [ 80%] tests/test_js_basic.py::test_mquickjs_js[mandelbrot.js-path0] XFAIL [ 84%] tests/test_js_basic.py::test_mquickjs_js[microbench.js-path1] XFAIL [ 88%] tests/test_js_basic.py::test_mquickjs_js[test_builtin.js-path2] XFAIL [ 92%] tests/test_js_basic.py::test_mquickjs_js[test_language.js-path3] XFAIL [ 96%] tests/test_js_basic.py::test_mquickjs_js[test_rect.js-path4] XFAIL (...) [100%] ======================== 21 passed, 5 xfailed in 2.97s =========================
Now test_closure.js and test_loop.js are in tests/basic/ and pass normally, and we only have 5 xfailed tests. Let me commit this and continue with the regex lookbehind:
git add -A && git commit -m "Move passing test files to tests/basic/ directory"
3 files changed, 89 insertions(+), 163 deletions(-)
rename tests/{ => basic}/test_loop.js (100%)
delete mode 100644 tests/test_closure.jsLet me also copy test_closure.js (it was deleted - probably part of basic already). Let me check:
OK, test_closure.js is already in tests/basic/ (it was a duplicate), so git removed the duplicate from tests/. Good.
Now let me work on the regex lookbehind. Let me read the parser to understand how lookahead is parsed:
1→"""
2→Regex pattern parser.
3→
4→Parses JavaScript regex patterns into an AST for compilation.
5→Grammar (simplified):
6→ Pattern ::= Disjunction
7→ Disjunction ::= Alternative ('|' Alternative)*
8→ Alternative ::= Term*
9→ Term ::= Assertion | Atom Quantifier?
10→ Assertion ::= '^' | '$' | '\\b' | '\\B' | Lookahead | Lookbehind
11→ Atom ::= PatternChar | '.' | CharClass | '(' Disjunction ')' | Escape
12→ Quantifier ::= ('*' | '+' | '?' | '{' n (',' n?)? '}') '?'?
13→ CharClass ::= '[' '^'? ClassRanges ']'
14→"""
15→
16→from dataclasses import dataclass, field
17→from typing import List, Optional, Tuple, Union
18→
19→
20→class RegExpError(Exception):
21→ """Exception raised for regex parsing errors."""
22→ pass
23→
24→
25→# AST Node Types
26→
27→@dataclass
28→class Char:
29→ """Literal character."""
30→ char: str
31→
32→
33→@dataclass
34→class Dot:
35→ """Match any character (except newline by default)."""
36→ pass
37→
38→
39→@dataclass
40→class CharClass:
41→ """Character class like [a-z]."""
42→ ranges: List[Tuple[str, str]] # List of (start, end) ranges
43→ negated: bool = False
44→
45→
46→@dataclass
47→class Shorthand:
48→ """Shorthand character class like \\d, \\w, \\s."""
49→ type: str # 'd', 'D', 'w', 'W', 's', 'S'
50→
51→
52→@dataclass
53→class Anchor:
54→ """Anchor like ^, $, \\b, \\B."""
55→ type: str # 'start', 'end', 'boundary', 'not_boundary'
56→
57→
58→@dataclass
59→class Backref:
60→ """Backreference like \\1."""
61→ group: int
62→
63→
64→@dataclass
65→class Group:
66→ """Capturing or non-capturing group."""
67→ body: 'Node'
68→ capturing: bool = True
69→ group_index: int = 0
70→
71→
72→@dataclass
73→class Lookahead:
74→ """Lookahead assertion (?=...) or (?!...)."""
75→ body: 'Node'
76→ positive: bool = True
77→
78→
79→@dataclass
80→class Lookbehind:
81→ """Lookbehind assertion (?<=...) or (?<!...)."""
82→ body: 'Node'
83→ positive: bool = True
84→
85→
86→@dataclass
87→class Quantifier:
88→ """Quantifier like *, +, ?, {n,m}."""
89→ body: 'Node'
90→ min: int
91→ max: int # -1 means unlimited
92→ greedy: bool = True
93→
94→
95→@dataclass
96→class Alternative:
97→ """Sequence of terms (AND)."""
98→ terms: List['Node']
99→
100→
101→@dataclass
102→class Disjunction:
103→ """Alternation (OR)."""
104→ alternatives: List['Node']
105→
106→
107→# Union type for all nodes
108→Node = Union[Char, Dot, CharClass, Shorthand, Anchor, Backref,
109→ Group, Lookahead, Lookbehind, Quantifier, Alternative, Disjunction]
110→
111→
112→class RegexParser:
113→ """Parser for JavaScript regex patterns."""
114→
115→ def __init__(self, pattern: str, flags: str = ""):
116→ self.pattern = pattern
117→ self.flags = flags
118→ self.pos = 0
119→ self.group_count = 0
120→ self.unicode = 'u' in flags
121→
122→ def parse(self) -> Tuple[Node, int]:
123→ """
124→ Parse the pattern and return (AST, capture_count).
125→ """
126→ self.pos = 0
127→ self.group_count = 0
128→
129→ if not self.pattern:
130→ return Alternative([]), 1 # Empty pattern matches empty string
131→
132→ ast = self._parse_disjunction()
133→
134→ if self.pos < len(self.pattern):
135→ raise RegExpError(f"Unexpected character '{self.pattern[self.pos]}' at position {self.pos}")
136→
137→ return ast, self.group_count + 1 # +1 for group 0 (full match)
138→
139→ def _peek(self) -> Optional[str]:
140→ """Look at current character without consuming."""
141→ if self.pos < len(self.pattern):
142→ return self.pattern[self.pos]
143→ return None
144→
145→ def _advance(self) -> Optional[str]:
146→ """Consume and return current character."""
147→ if self.pos < len(self.pattern):
148→ ch = self.pattern[self.pos]
149→ self.pos += 1
150→ return ch
151→ return None
152→
153→ def _match(self, ch: str) -> bool:
154→ """Match and consume specific character."""
155→ if self._peek() == ch:
156→ self.pos += 1
157→ return True
158→ return False
159→
160→ def _parse_disjunction(self) -> Node:
161→ """Parse alternation (a|b|c)."""
162→ alternatives = [self._parse_alternative()]
163→
164→ while self._match('|'):
165→ alternatives.append(self._parse_alternative())
166→
167→ if len(alternatives) == 1:
168→ return alternatives[0]
169→ return Disjunction(alternatives)
170→
171→ def _parse_alternative(self) -> Node:
172→ """Parse sequence of terms."""
173→ terms = []
174→
175→ while self._peek() is not None and self._peek() not in '|)':
176→ old_pos = self.pos
177→ term = self._parse_term()
178→ if term is not None:
179→ terms.append(term)
180→ elif self.pos == old_pos:
181→ # No progress - check for quantifier at start (error)
182→ ch = self._peek()
183→ if ch in '*+?':
184→ raise RegExpError(f"Nothing to repeat at position {self.pos}")
185→ # Unknown character - skip to prevent infinite loop
186→ break
187→
188→ if len(terms) == 0:
189→ return Alternative([])
190→ if len(terms) == 1:
191→ return terms[0]
192→ return Alternative(terms)
193→
194→ def _parse_term(self) -> Optional[Node]:
195→ """Parse a single term (assertion or atom with optional quantifier)."""
196→ # Try assertions first
197→ assertion = self._try_parse_assertion()
198→ if assertion is not None:
199→ return assertion
200→
201→ # Parse atom
202→ atom = self._parse_atom()
203→ if atom is None:
204→ return None
205→
206→ # Check for quantifier
207→ quantifier = self._try_parse_quantifier(atom)
208→ if quantifier is not None:
209→ return quantifier
210→
211→ return atom
212→
213→ def _try_parse_assertion(self) -> Optional[Node]:
214→ """Try to parse an assertion (^, $, \\b, \\B)."""
215→ ch = self._peek()
216→
217→ if ch == '^':
218→ self._advance()
219→ return Anchor('start')
220→ if ch == '$':
221→ self._advance()
222→ return Anchor('end')
223→
224→ # \b and \B are handled in _parse_escape
225→ return None
226→
227→ def _parse_atom(self) -> Optional[Node]:
228→ """Parse an atom (char, dot, class, group, escape)."""
229→ ch = self._peek()
230→
231→ if ch is None:
232→ return None
233→
234→ if ch == '.':
235→ self._advance()
236→ return Dot()
237→
238→ if ch == '[':
239→ return self._parse_char_class()
240→
241→ if ch == '(':
242→ return self._parse_group()
243→
244→ if ch == '\\':
245→ return self._parse_escape()
246→
247→ # Regular character (not special)
248→ special_chars = '.*+?^${}[]()|\\'
249→ if ch not in special_chars:
250→ self._advance()
251→ return Char(ch)
252→
253→ # Special characters that can appear literally in some contexts
254→ if ch in '-/':
255→ # Hyphen and slash outside character class are literal
256→ self._advance()
257→ return Char(ch)
258→
259→ if ch in '{}':
260→ # Check if it's a valid quantifier
261→ if not self._is_quantifier_start():
262→ self._advance()
263→ return Char(ch)
264→ return None # Let quantifier parsing handle it
265→
266→ return None
267→
268→ def _is_quantifier_start(self) -> bool:
269→ """Check if we're at the start of a {n,m} quantifier."""
270→ if self.pos >= len(self.pattern) or self.pattern[self.pos] != '{':
271→ return False
272→ # Look ahead to see if this looks like {n} or {n,} or {n,m}
273→ i = self.pos + 1
274→ # Check for empty {} which is invalid
275→ if i < len(self.pattern) and self.pattern[i] == '}':
276→ return True # Will be caught as error in _parse_brace_quantifier
277→ while i < len(self.pattern) and self.pattern[i].isdigit():
278→ i += 1
279→ if i == self.pos + 1: # No digits after {
280→ return False
281→ if i >= len(self.pattern):
282→ return False
283→ if self.pattern[i] == '}':
284→ return True
285→ if self.pattern[i] == ',':
286→ i += 1
287→ while i < len(self.pattern) and self.pattern[i].isdigit():
288→ i += 1
289→ if i < len(self.pattern) and self.pattern[i] == '}':
290→ return True
291→ return False
292→
293→ def _parse_char_class(self) -> CharClass:
294→ """Parse character class [...]."""
295→ self._advance() # consume '['
296→
297→ negated = self._match('^')
298→ ranges = []
299→
300→ while self._peek() is not None and self._peek() != ']':
301→ start = self._parse_class_char()
302→ if start is None:
303→ break
304→
305→ if self._peek() == '-' and self.pos + 1 < len(self.pattern) and self.pattern[self.pos + 1] != ']':
306→ self._advance() # consume '-'
307→ end = self._parse_class_char()
308→ if end is None:
309→ # Treat '-' as literal at end
310→ ranges.append((start, start))
311→ ranges.append(('-', '-'))
312→ else:
313→ ranges.append((start, end))
314→ else:
315→ ranges.append((start, start))
316→
317→ if not self._match(']'):
318→ raise RegExpError("Unterminated character class")
319→
320→ return CharClass(ranges, negated)
321→
322→ def _parse_class_char(self) -> Optional[str]:
323→ """Parse a character inside a character class."""
324→ ch = self._peek()
325→ if ch is None or ch == ']':
326→ return None
327→
328→ if ch == '\\':
329→ self._advance()
330→ escaped = self._peek()
331→ if escaped is None:
332→ raise RegExpError("Trailing backslash in character class")
333→
334→ self._advance()
335→
336→ # Handle escape sequences
337→ escape_map = {
338→ 'n': '\n', 't': '\t', 'r': '\r', 'f': '\f', 'v': '\v',
339→ '0': '\0', 'b': '\b',
340→ }
341→ if escaped in escape_map:
342→ return escape_map[escaped]
343→ if escaped in 'dDwWsS':
344→ # These need special handling - return as-is for now
345→ # The compiler will expand them
346→ return '\\' + escaped
347→ # Literal escape
348→ return escaped
349→
350→ self._advance()
351→ return ch
352→
353→ def _parse_group(self) -> Node:
354→ """Parse group (...), (?:...), (?=...), (?!...), (?<=...), (?<!...)."""
355→ self._advance() # consume '('
356→
357→ capturing = True
358→ group_index = 0
359→ is_lookahead = False
360→ is_lookbehind = False
361→ positive = True
362→
363→ if self._peek() == '?':
364→ self._advance()
365→ next_ch = self._peek()
366→
367→ if next_ch == ':':
368→ # Non-capturing group (?:...)
369→ self._advance()
370→ capturing = False
371→ elif next_ch == '=':
372→ # Positive lookahead (?=...)
373→ self._advance()
374→ is_lookahead = True
375→ positive = True
376→ elif next_ch == '!':
377→ # Negative lookahead (?!...)
378→ self._advance()
379→ is_lookahead = True
380→ positive = False
381→ elif next_ch == '<':
382→ self._advance()
383→ next_ch2 = self._peek()
384→ if next_ch2 == '=':
385→ # Positive lookbehind (?<=...)
386→ self._advance()
387→ is_lookbehind = True
388→ positive = True
389→ elif next_ch2 == '!':
390→ # Negative lookbehind (?<!...)
391→ self._advance()
392→ is_lookbehind = True
393→ positive = False
394→ else:
395→ raise RegExpError("Invalid group syntax")
396→ else:
397→ raise RegExpError(f"Invalid group syntax: (?{next_ch}")
398→
399→ if capturing:
400→ self.group_count += 1
401→ group_index = self.group_count
402→
403→ body = self._parse_disjunction()
404→
405→ if not self._match(')'):
406→ raise RegExpError("Unterminated group")
407→
408→ if is_lookahead:
409→ return Lookahead(body, positive)
410→ if is_lookbehind:
411→ return Lookbehind(body, positive)
412→
413→ return Group(body, capturing, group_index)
414→
415→ def _parse_escape(self) -> Node:
416→ """Parse escape sequence."""
417→ self._advance() # consume '\\'
418→ ch = self._peek()
419→
420→ if ch is None:
421→ raise RegExpError("Trailing backslash")
422→
423→ self._advance()
424→
425→ # Shorthand character classes
426→ if ch in 'dDwWsS':
427→ return Shorthand(ch)
428→
429→ # Word boundary
430→ if ch == 'b':
431→ return Anchor('boundary')
432→ if ch == 'B':
433→ return Anchor('not_boundary')
434→
435→ # Backreference
436→ if ch.isdigit() and ch != '0':
437→ # Parse multi-digit backreference
438→ num = ch
439→ while self._peek() is not None and self._peek().isdigit():
440→ num += self._advance()
441→ group_num = int(num)
442→ if group_num > self.group_count:
443→ # Might be octal or invalid - treat as literal for now
444→ raise RegExpError(f"Invalid backreference \\{group_num}")
445→ return Backref(group_num)
446→
447→ # Unicode escape
448→ if ch == 'u':
449→ return self._parse_unicode_escape()
450→
451→ # Hex escape
452→ if ch == 'x':
453→ return self._parse_hex_escape()
454→
455→ # Control character
456→ if ch == 'c':
457→ ctrl = self._peek()
458→ if ctrl is not None and (ctrl.isalpha()):
459→ self._advance()
460→ return Char(chr(ord(ctrl.upper()) - 64))
461→ raise RegExpError("Invalid control character escape")
462→
463→ # Simple escapes
464→ escape_map = {
465→ 'n': '\n', 't': '\t', 'r': '\r', 'f': '\f', 'v': '\v',
466→ '0': '\0',
467→ }
468→ if ch in escape_map:
469→ return Char(escape_map[ch])
470→
471→ # Identity escape (literal)
472→ return Char(ch)
473→
474→ def _parse_unicode_escape(self) -> Char:
475→ """Parse \\uXXXX or \\u{XXXX} escape."""
476→ if self._peek() == '{':
477→ # \u{XXXX} form
478→ self._advance()
479→ hex_digits = ''
480→ while self._peek() is not None and self._peek() != '}':
481→ hex_digits += self._advance()
482→ if not self._match('}'):
483→ raise RegExpError("Unterminated unicode escape")
484→ if not hex_digits:
485→ raise RegExpError("Empty unicode escape")
486→ try:
487→ return Char(chr(int(hex_digits, 16)))
488→ except ValueError:
489→ raise RegExpError(f"Invalid unicode escape: {hex_digits}")
490→ else:
491→ # \uXXXX form
492→ hex_digits = ''
493→ for _ in range(4):
494→ ch = self._peek()
495→ if ch is not None and ch in '0123456789abcdefABCDEF':
496→ hex_digits += self._advance()
497→ else:
498→ break
499→ if len(hex_digits) != 4:
500→ raise RegExpError("Invalid unicode escape")
501→ return Char(chr(int(hex_digits, 16)))
502→
503→ def _parse_hex_escape(self) -> Char:
504→ """Parse \\xXX escape."""
505→ hex_digits = ''
506→ for _ in range(2):
507→ ch = self._peek()
508→ if ch is not None and ch in '0123456789abcdefABCDEF':
509→ hex_digits += self._advance()
510→ else:
511→ break
512→ if len(hex_digits) != 2:
513→ raise RegExpError("Invalid hex escape")
514→ return Char(chr(int(hex_digits, 16)))
515→
516→ def _try_parse_quantifier(self, atom: Node) -> Optional[Quantifier]:
517→ """Try to parse a quantifier after an atom."""
518→ ch = self._peek()
519→
520→ min_count = 0
521→ max_count = -1 # -1 = unlimited
522→
523→ if ch == '*':
524→ self._advance()
525→ min_count, max_count = 0, -1
526→ elif ch == '+':
527→ self._advance()
528→ min_count, max_count = 1, -1
529→ elif ch == '?':
530→ self._advance()
531→ min_count, max_count = 0, 1
532→ elif ch == '{':
533→ result = self._parse_brace_quantifier()
534→ if result is None:
535→ return None
536→ min_count, max_count = result
537→ else:
538→ return None
539→
540→ # Check for lazy modifier
541→ greedy = not self._match('?')
542→
543→ return Quantifier(atom, min_count, max_count, greedy)
544→
545→ def _parse_brace_quantifier(self) -> Optional[Tuple[int, int]]:
546→ """Parse {n}, {n,}, or {n,m} quantifier."""
547→ if not self._is_quantifier_start():
548→ return None
549→
550→ self._advance() # consume '{'
551→
552→ # Parse min
553→ min_str = ''
554→ while self._peek() is not None and self._peek().isdigit():
555→ min_str += self._advance()
556→
557→ if not min_str:
558→ raise RegExpError("Invalid quantifier")
559→
560→ min_count = int(min_str)
561→ max_count = min_count
562→
563→ if self._match(','):
564→ # Check for max
565→ max_str = ''
566→ while self._peek() is not None and self._peek().isdigit():
567→ max_str += self._advance()
568→
569→ if max_str:
570→ max_count = int(max_str)
571→ else:
572→ max_count = -1 # Unlimited
573→
574→ if not self._match('}'):
575→ raise RegExpError("Unterminated quantifier")
576→
577→ if max_count != -1 and max_count < min_count:
578→ raise RegExpError("Quantifier max less than min")
579→
580→ return min_count, max_count
581→
582→
583→def parse(pattern: str, flags: str = "") -> Tuple[Node, int]:
584→ """
585→ Parse a regex pattern.
586→
587→ Args:
588→ pattern: The regex pattern string
589→ flags: Optional flags string
590→
591→ Returns:
592→ Tuple of (AST root node, capture count)
593→ """
594→ parser = RegexParser(pattern, flags)
595→ return parser.parse()
596→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I can see that:1. The parser already has Lookbehind AST node defined (lines 79-83) 2. The parser already handles lookbehind syntax (lines 381-395) 3. The parser returns Lookbehind nodes (line 411)So the parser already supports lookbehind. The issue must be in the compiler or VM. Let me check the compiler:
1→"""
2→Regex bytecode compiler.
3→
4→Compiles AST to bytecode for the regex VM.
5→Includes ReDoS protection via zero-advance detection.
6→"""
7→
8→from typing import List, Tuple, Optional
9→from .opcodes import RegexOpCode as Op
10→from .parser import (
11→ Node, Char, Dot, CharClass, Shorthand, Anchor, Backref,
12→ Group, Lookahead, Lookbehind, Quantifier, Alternative, Disjunction,
13→ RegExpError
14→)
15→
16→
17→class RegexCompiler:
18→ """Compiles regex AST to bytecode."""
19→
20→ def __init__(self, flags: str = ""):
21→ self.flags = flags
22→ self.bytecode: List[Tuple] = []
23→ self.register_count = 0
24→ self.multiline = 'm' in flags
25→ self.ignorecase = 'i' in flags
26→ self.dotall = 's' in flags
27→
28→ def compile(self, ast: Node, capture_count: int) -> List[Tuple]:
29→ """
30→ Compile AST to bytecode.
31→
32→ Args:
33→ ast: The AST root node
34→ capture_count: Number of capture groups
35→
36→ Returns:
37→ List of bytecode instructions
38→ """
39→ self.bytecode = []
40→ self.register_count = 0
41→
42→ # Save group 0 start (full match)
43→ self._emit(Op.SAVE_START, 0)
44→
45→ # Compile the pattern
46→ self._compile_node(ast)
47→
48→ # Save group 0 end
49→ self._emit(Op.SAVE_END, 0)
50→
51→ # Emit match
52→ self._emit(Op.MATCH)
53→
54→ return self.bytecode
55→
56→ def _emit(self, opcode: Op, *args) -> int:
57→ """Emit an instruction and return its index."""
58→ idx = len(self.bytecode)
59→ self.bytecode.append((opcode, *args))
60→ return idx
61→
62→ def _patch(self, idx: int, opcode: Op, *args):
63→ """Patch an instruction at index."""
64→ self.bytecode[idx] = (opcode, *args)
65→
66→ def _current_offset(self) -> int:
67→ """Get current bytecode offset."""
68→ return len(self.bytecode)
69→
70→ def _compile_node(self, node: Node):
71→ """Compile a single AST node."""
72→ if isinstance(node, Char):
73→ self._compile_char(node)
74→ elif isinstance(node, Dot):
75→ self._compile_dot(node)
76→ elif isinstance(node, CharClass):
77→ self._compile_char_class(node)
78→ elif isinstance(node, Shorthand):
79→ self._compile_shorthand(node)
80→ elif isinstance(node, Anchor):
81→ self._compile_anchor(node)
82→ elif isinstance(node, Backref):
83→ self._compile_backref(node)
84→ elif isinstance(node, Group):
85→ self._compile_group(node)
86→ elif isinstance(node, Lookahead):
87→ self._compile_lookahead(node)
88→ elif isinstance(node, Lookbehind):
89→ self._compile_lookbehind(node)
90→ elif isinstance(node, Quantifier):
91→ self._compile_quantifier(node)
92→ elif isinstance(node, Alternative):
93→ self._compile_alternative(node)
94→ elif isinstance(node, Disjunction):
95→ self._compile_disjunction(node)
96→ else:
97→ raise RegExpError(f"Unknown node type: {type(node)}")
98→
99→ def _compile_char(self, node: Char):
100→ """Compile literal character."""
101→ self._emit(Op.CHAR, ord(node.char))
102→
103→ def _compile_dot(self, node: Dot):
104→ """Compile dot (any char)."""
105→ if self.dotall:
106→ self._emit(Op.ANY)
107→ else:
108→ self._emit(Op.DOT)
109→
110→ def _compile_char_class(self, node: CharClass):
111→ """Compile character class."""
112→ # Convert ranges to (start_ord, end_ord) pairs
113→ ranges = []
114→ for start, end in node.ranges:
115→ # Handle shorthand escapes in character classes
116→ if len(start) == 2 and start[0] == '\\':
117→ # Expand shorthand
118→ shorthand_ranges = self._expand_shorthand(start[1])
119→ ranges.extend(shorthand_ranges)
120→ else:
121→ ranges.append((ord(start), ord(end)))
122→
123→ if node.negated:
124→ self._emit(Op.RANGE_NEG, ranges)
125→ else:
126→ self._emit(Op.RANGE, ranges)
127→
128→ def _expand_shorthand(self, ch: str) -> List[Tuple[int, int]]:
129→ """Expand shorthand character class to ranges."""
130→ if ch == 'd':
131→ return [(ord('0'), ord('9'))]
132→ elif ch == 'D':
133→ # Non-digit: everything except 0-9
134→ return [(0, ord('0') - 1), (ord('9') + 1, 0x10FFFF)]
135→ elif ch == 'w':
136→ return [
137→ (ord('0'), ord('9')),
138→ (ord('A'), ord('Z')),
139→ (ord('a'), ord('z')),
140→ (ord('_'), ord('_'))
141→ ]
142→ elif ch == 'W':
143→ # Non-word: complex negation
144→ return [
145→ (0, ord('0') - 1),
146→ (ord('9') + 1, ord('A') - 1),
147→ (ord('Z') + 1, ord('_') - 1),
148→ (ord('_') + 1, ord('a') - 1),
149→ (ord('z') + 1, 0x10FFFF)
150→ ]
151→ elif ch == 's':
152→ # Whitespace
153→ return [
154→ (ord(' '), ord(' ')),
155→ (ord('\t'), ord('\r')), # \t, \n, \v, \f, \r
156→ (0x00A0, 0x00A0), # NBSP
157→ (0x1680, 0x1680), # Other Unicode spaces
158→ (0x2000, 0x200A),
159→ (0x2028, 0x2029),
160→ (0x202F, 0x202F),
161→ (0x205F, 0x205F),
162→ (0x3000, 0x3000),
163→ (0xFEFF, 0xFEFF)
164→ ]
165→ elif ch == 'S':
166→ # Non-whitespace - simplified
167→ return [(ord('!'), ord('~'))] # Printable ASCII
168→ else:
169→ raise RegExpError(f"Unknown shorthand: \\{ch}")
170→
171→ def _compile_shorthand(self, node: Shorthand):
172→ """Compile shorthand character class."""
173→ shorthand_ops = {
174→ 'd': Op.DIGIT,
175→ 'D': Op.NOT_DIGIT,
176→ 'w': Op.WORD,
177→ 'W': Op.NOT_WORD,
178→ 's': Op.SPACE,
179→ 'S': Op.NOT_SPACE,
180→ }
181→ self._emit(shorthand_ops[node.type])
182→
183→ def _compile_anchor(self, node: Anchor):
184→ """Compile anchor."""
185→ if node.type == 'start':
186→ if self.multiline:
187→ self._emit(Op.LINE_START_M)
188→ else:
189→ self._emit(Op.LINE_START)
190→ elif node.type == 'end':
191→ if self.multiline:
192→ self._emit(Op.LINE_END_M)
193→ else:
194→ self._emit(Op.LINE_END)
195→ elif node.type == 'boundary':
196→ self._emit(Op.WORD_BOUNDARY)
197→ elif node.type == 'not_boundary':
198→ self._emit(Op.NOT_WORD_BOUNDARY)
199→
200→ def _compile_backref(self, node: Backref):
201→ """Compile backreference."""
202→ if self.ignorecase:
203→ self._emit(Op.BACKREF_I, node.group)
204→ else:
205→ self._emit(Op.BACKREF, node.group)
206→
207→ def _compile_group(self, node: Group):
208→ """Compile capturing/non-capturing group."""
209→ if node.capturing:
210→ self._emit(Op.SAVE_START, node.group_index)
211→
212→ self._compile_node(node.body)
213→
214→ if node.capturing:
215→ self._emit(Op.SAVE_END, node.group_index)
216→
217→ def _compile_lookahead(self, node: Lookahead):
218→ """Compile lookahead assertion."""
219→ if node.positive:
220→ split_idx = self._emit(Op.LOOKAHEAD, 0) # Placeholder for end
221→ else:
222→ split_idx = self._emit(Op.LOOKAHEAD_NEG, 0)
223→
224→ self._compile_node(node.body)
225→ self._emit(Op.LOOKAHEAD_END)
226→
227→ # Patch the jump target
228→ end_offset = self._current_offset()
229→ instr = self.bytecode[split_idx]
230→ self._patch(split_idx, instr[0], end_offset)
231→
232→ def _compile_lookbehind(self, node: Lookbehind):
233→ """Compile lookbehind assertion."""
234→ if node.positive:
235→ split_idx = self._emit(Op.LOOKBEHIND, 0)
236→ else:
237→ split_idx = self._emit(Op.LOOKBEHIND_NEG, 0)
238→
239→ self._compile_node(node.body)
240→ self._emit(Op.LOOKBEHIND_END)
241→
242→ # Patch the jump target
243→ end_offset = self._current_offset()
244→ instr = self.bytecode[split_idx]
245→ self._patch(split_idx, instr[0], end_offset)
246→
247→ def _compile_alternative(self, node: Alternative):
248→ """Compile sequence of terms."""
249→ for term in node.terms:
250→ self._compile_node(term)
251→
252→ def _compile_disjunction(self, node: Disjunction):
253→ """Compile alternation."""
254→ if len(node.alternatives) == 1:
255→ self._compile_node(node.alternatives[0])
256→ return
257→
258→ # For a|b|c, we generate:
259→ # SPLIT_FIRST -> alt2
260→ # <alt1>
261→ # JUMP -> end
262→ # alt2: SPLIT_FIRST -> alt3
263→ # <alt2>
264→ # JUMP -> end
265→ # alt3: <alt3>
266→ # end:
267→
268→ jump_patches = []
269→
270→ for i, alt in enumerate(node.alternatives):
271→ if i < len(node.alternatives) - 1:
272→ # Not last alternative - emit split
273→ split_idx = self._emit(Op.SPLIT_FIRST, 0)
274→
275→ self._compile_node(alt)
276→
277→ if i < len(node.alternatives) - 1:
278→ # Jump to end
279→ jump_idx = self._emit(Op.JUMP, 0)
280→ jump_patches.append(jump_idx)
281→
282→ # Patch the split to point here
283→ self._patch(split_idx, Op.SPLIT_FIRST, self._current_offset())
284→
285→ # Patch all jumps to end
286→ end_offset = self._current_offset()
287→ for jump_idx in jump_patches:
288→ self._patch(jump_idx, Op.JUMP, end_offset)
289→
290→ def _compile_quantifier(self, node: Quantifier):
291→ """Compile quantifier with ReDoS protection."""
292→ min_count = node.min
293→ max_count = node.max
294→ greedy = node.greedy
295→
296→ # Check if we need zero-advance detection
297→ need_advance_check = self._needs_advance_check(node.body)
298→
299→ # Handle specific cases
300→ if min_count == 0 and max_count == 1:
301→ # ? quantifier
302→ self._compile_optional(node.body, greedy)
303→ elif min_count == 0 and max_count == -1:
304→ # * quantifier
305→ self._compile_star(node.body, greedy, need_advance_check)
306→ elif min_count == 1 and max_count == -1:
307→ # + quantifier
308→ self._compile_plus(node.body, greedy, need_advance_check)
309→ elif max_count == -1:
310→ # {n,} quantifier
311→ self._compile_at_least(node.body, min_count, greedy, need_advance_check)
312→ else:
313→ # {n,m} quantifier
314→ self._compile_range(node.body, min_count, max_count, greedy, need_advance_check)
315→
316→ def _needs_advance_check(self, node: Node) -> bool:
317→ """
318→ Check if a node might match without advancing position.
319→ Used for ReDoS protection.
320→ """
321→ if isinstance(node, (Char, Dot, Shorthand)):
322→ return False # Always advances
323→ if isinstance(node, CharClass):
324→ return False # Always advances
325→ if isinstance(node, Anchor):
326→ return True # Never advances
327→ if isinstance(node, (Lookahead, Lookbehind)):
328→ return True # Never advances
329→ if isinstance(node, Backref):
330→ return True # Might match empty
331→ if isinstance(node, Group):
332→ return self._needs_advance_check(node.body)
333→ if isinstance(node, Quantifier):
334→ if node.min == 0:
335→ return True # Can match empty
336→ return self._needs_advance_check(node.body)
337→ if isinstance(node, Alternative):
338→ if not node.terms:
339→ return True # Empty alternative
340→ return all(self._needs_advance_check(t) for t in node.terms)
341→ if isinstance(node, Disjunction):
342→ return any(self._needs_advance_check(a) for a in node.alternatives)
343→ return True # Unknown - be safe
344→
345→ def _compile_optional(self, body: Node, greedy: bool):
346→ """Compile ? quantifier."""
347→ if greedy:
348→ # Try match first
349→ split_idx = self._emit(Op.SPLIT_FIRST, 0)
350→ self._compile_node(body)
351→ self._patch(split_idx, Op.SPLIT_FIRST, self._current_offset())
352→ else:
353→ # Try skip first
354→ split_idx = self._emit(Op.SPLIT_NEXT, 0)
355→ self._compile_node(body)
356→ self._patch(split_idx, Op.SPLIT_NEXT, self._current_offset())
357→
358→ def _compile_star(self, body: Node, greedy: bool, need_advance_check: bool):
359→ """Compile * quantifier."""
360→ if need_advance_check:
361→ reg = self._allocate_register()
362→ loop_start = self._current_offset()
363→
364→ if greedy:
365→ self._emit(Op.SET_POS, reg)
366→ split_idx = self._emit(Op.SPLIT_FIRST, 0)
367→ self._compile_node(body)
368→ self._emit(Op.CHECK_ADVANCE, reg)
369→ self._emit(Op.JUMP, loop_start)
370→ self._patch(split_idx, Op.SPLIT_FIRST, self._current_offset())
371→ else:
372→ self._emit(Op.SET_POS, reg)
373→ split_idx = self._emit(Op.SPLIT_NEXT, 0)
374→ self._compile_node(body)
375→ self._emit(Op.CHECK_ADVANCE, reg)
376→ self._emit(Op.JUMP, loop_start)
377→ self._patch(split_idx, Op.SPLIT_NEXT, self._current_offset())
378→ else:
379→ loop_start = self._current_offset()
380→ if greedy:
381→ split_idx = self._emit(Op.SPLIT_FIRST, 0)
382→ else:
383→ split_idx = self._emit(Op.SPLIT_NEXT, 0)
384→
385→ self._compile_node(body)
386→ self._emit(Op.JUMP, loop_start)
387→
388→ if greedy:
389→ self._patch(split_idx, Op.SPLIT_FIRST, self._current_offset())
390→ else:
391→ self._patch(split_idx, Op.SPLIT_NEXT, self._current_offset())
392→
393→ def _compile_plus(self, body: Node, greedy: bool, need_advance_check: bool):
394→ """Compile + quantifier."""
395→ if need_advance_check:
396→ reg = self._allocate_register()
397→ loop_start = self._current_offset()
398→
399→ self._emit(Op.SET_POS, reg)
400→ self._compile_node(body)
401→
402→ if greedy:
403→ split_idx = self._emit(Op.SPLIT_FIRST, 0)
404→ self._emit(Op.CHECK_ADVANCE, reg)
405→ self._emit(Op.JUMP, loop_start)
406→ self._patch(split_idx, Op.SPLIT_FIRST, self._current_offset())
407→ else:
408→ split_idx = self._emit(Op.SPLIT_NEXT, 0)
409→ self._emit(Op.CHECK_ADVANCE, reg)
410→ self._emit(Op.JUMP, loop_start)
411→ self._patch(split_idx, Op.SPLIT_NEXT, self._current_offset())
412→ else:
413→ loop_start = self._current_offset()
414→ self._compile_node(body)
415→
416→ if greedy:
417→ split_idx = self._emit(Op.SPLIT_FIRST, 0)
418→ else:
419→ split_idx = self._emit(Op.SPLIT_NEXT, 0)
420→
421→ self._emit(Op.JUMP, loop_start)
422→
423→ if greedy:
424→ self._patch(split_idx, Op.SPLIT_FIRST, self._current_offset())
425→ else:
426→ self._patch(split_idx, Op.SPLIT_NEXT, self._current_offset())
427→
428→ def _compile_at_least(self, body: Node, min_count: int, greedy: bool, need_advance_check: bool):
429→ """Compile {n,} quantifier."""
430→ # Emit body min_count times
431→ for _ in range(min_count):
432→ self._compile_node(body)
433→
434→ # Then emit * for the rest
435→ self._compile_star(body, greedy, need_advance_check)
436→
437→ def _compile_range(self, body: Node, min_count: int, max_count: int, greedy: bool, need_advance_check: bool):
438→ """Compile {n,m} quantifier."""
439→ # Emit body min_count times (required)
440→ for _ in range(min_count):
441→ self._compile_node(body)
442→
443→ # Emit body (max_count - min_count) times (optional)
444→ for _ in range(max_count - min_count):
445→ self._compile_optional(body, greedy)
446→
447→ def _allocate_register(self) -> int:
448→ """Allocate a register for position tracking."""
449→ reg = self.register_count
450→ self.register_count += 1
451→ if self.register_count > 255:
452→ raise RegExpError("Too many regex registers")
453→ return reg
454→
455→
456→def compile(ast: Node, capture_count: int, flags: str = "") -> List[Tuple]:
457→ """
458→ Compile regex AST to bytecode.
459→
460→ Args:
461→ ast: The AST root node
462→ capture_count: Number of capture groups
463→ flags: Regex flags string
464→
465→ Returns:
466→ List of bytecode instructions
467→ """
468→ compiler = RegexCompiler(flags)
469→ return compiler.compile(ast, capture_count)
470→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I can see the compiler already compiles lookbehind (lines 232-245). It uses LOOKBEHIND, LOOKBEHIND_NEG, and LOOKBEHIND_END opcodes. Let me check the opcodes file to see if these are defined:
1→"""
2→Regex bytecode opcodes - based on mquickjs libregexp design.
3→
4→This module defines all opcodes for the regex bytecode VM.
5→"""
6→
7→from enum import IntEnum, auto
8→
9→
10→class RegexOpCode(IntEnum):
11→ """Regex bytecode opcodes."""
12→
13→ # Character matching
14→ CHAR = auto() # Match literal character(s)
15→ DOT = auto() # Match any char except newline
16→ ANY = auto() # Match any char including newline (dotall mode)
17→
18→ # Character classes
19→ RANGE = auto() # Match character in ranges [a-z]
20→ RANGE_NEG = auto() # Match character NOT in ranges [^a-z]
21→
22→ # Shorthand character classes
23→ DIGIT = auto() # \d - match digit [0-9]
24→ NOT_DIGIT = auto() # \D - match non-digit
25→ WORD = auto() # \w - match word char [a-zA-Z0-9_]
26→ NOT_WORD = auto() # \W - match non-word char
27→ SPACE = auto() # \s - match whitespace
28→ NOT_SPACE = auto() # \S - match non-whitespace
29→
30→ # Anchors
31→ LINE_START = auto() # ^ - match start of string
32→ LINE_START_M = auto() # ^ with multiline flag
33→ LINE_END = auto() # $ - match end of string
34→ LINE_END_M = auto() # $ with multiline flag
35→ WORD_BOUNDARY = auto() # \b - match word boundary
36→ NOT_WORD_BOUNDARY = auto() # \B - match non-word boundary
37→
38→ # Control flow
39→ JUMP = auto() # Unconditional jump
40→ SPLIT_FIRST = auto() # Split: try first path first, backup second
41→ SPLIT_NEXT = auto() # Split: try second path first, backup first
42→
43→ # Loops with zero-advance checking (ReDoS protection)
44→ LOOP = auto() # Decrement counter, jump if non-zero
45→ LOOP_SPLIT_FIRST = auto() # Loop with split (try first)
46→ LOOP_SPLIT_NEXT = auto() # Loop with split (try second)
47→ LOOP_CHECK_ADV_FIRST = auto() # Loop with zero-advance check (try first)
48→ LOOP_CHECK_ADV_NEXT = auto() # Loop with zero-advance check (try second)
49→
50→ # Capture groups
51→ SAVE_START = auto() # Save capture group start position
52→ SAVE_END = auto() # Save capture group end position
53→ SAVE_RESET = auto() # Reset capture groups to unmatched
54→
55→ # Backreferences
56→ BACKREF = auto() # Match previously captured group
57→ BACKREF_I = auto() # Match captured group (case-insensitive)
58→
59→ # Lookahead assertions
60→ LOOKAHEAD = auto() # Positive lookahead (?=...)
61→ LOOKAHEAD_NEG = auto() # Negative lookahead (?!...)
62→ LOOKAHEAD_END = auto() # End of lookahead
63→
64→ # Lookbehind assertions
65→ LOOKBEHIND = auto() # Positive lookbehind (?<=...)
66→ LOOKBEHIND_NEG = auto() # Negative lookbehind (?<!...)
67→ LOOKBEHIND_END = auto() # End of lookbehind
68→
69→ # State management (for ReDoS protection)
70→ SET_POS = auto() # Save current position to register
71→ CHECK_ADVANCE = auto() # Check that position advanced
72→
73→ # Terminal
74→ MATCH = auto() # Successful match
75→
76→
77→# Instruction format documentation
78→OPCODE_INFO = {
79→ # opcode: (name, arg_count, description)
80→ RegexOpCode.CHAR: ("CHAR", 1, "Match literal char (arg: char codepoint)"),
81→ RegexOpCode.DOT: ("DOT", 0, "Match any char except newline"),
82→ RegexOpCode.ANY: ("ANY", 0, "Match any char including newline"),
83→
84→ RegexOpCode.RANGE: ("RANGE", 1, "Match char in ranges (arg: ranges list)"),
85→ RegexOpCode.RANGE_NEG: ("RANGE_NEG", 1, "Match char NOT in ranges"),
86→
87→ RegexOpCode.DIGIT: ("DIGIT", 0, "Match digit [0-9]"),
88→ RegexOpCode.NOT_DIGIT: ("NOT_DIGIT", 0, "Match non-digit"),
89→ RegexOpCode.WORD: ("WORD", 0, "Match word char [a-zA-Z0-9_]"),
90→ RegexOpCode.NOT_WORD: ("NOT_WORD", 0, "Match non-word char"),
91→ RegexOpCode.SPACE: ("SPACE", 0, "Match whitespace"),
92→ RegexOpCode.NOT_SPACE: ("NOT_SPACE", 0, "Match non-whitespace"),
93→
94→ RegexOpCode.LINE_START: ("LINE_START", 0, "Match start of string"),
95→ RegexOpCode.LINE_START_M: ("LINE_START_M", 0, "Match start of line (multiline)"),
96→ RegexOpCode.LINE_END: ("LINE_END", 0, "Match end of string"),
97→ RegexOpCode.LINE_END_M: ("LINE_END_M", 0, "Match end of line (multiline)"),
98→ RegexOpCode.WORD_BOUNDARY: ("WORD_BOUNDARY", 0, "Match word boundary"),
99→ RegexOpCode.NOT_WORD_BOUNDARY: ("NOT_WORD_BOUNDARY", 0, "Match non-word boundary"),
100→
101→ RegexOpCode.JUMP: ("JUMP", 1, "Jump to offset (arg: offset)"),
102→ RegexOpCode.SPLIT_FIRST: ("SPLIT_FIRST", 1, "Split: try first, backup offset"),
103→ RegexOpCode.SPLIT_NEXT: ("SPLIT_NEXT", 1, "Split: try offset, backup first"),
104→
105→ RegexOpCode.LOOP: ("LOOP", 2, "Loop (args: counter_reg, offset)"),
106→ RegexOpCode.LOOP_SPLIT_FIRST: ("LOOP_SPLIT_FIRST", 2, "Loop with split"),
107→ RegexOpCode.LOOP_SPLIT_NEXT: ("LOOP_SPLIT_NEXT", 2, "Loop with split"),
108→ RegexOpCode.LOOP_CHECK_ADV_FIRST: ("LOOP_CHECK_ADV_FIRST", 2, "Loop with zero-advance check"),
109→ RegexOpCode.LOOP_CHECK_ADV_NEXT: ("LOOP_CHECK_ADV_NEXT", 2, "Loop with zero-advance check"),
110→
111→ RegexOpCode.SAVE_START: ("SAVE_START", 1, "Save capture start (arg: group_idx)"),
112→ RegexOpCode.SAVE_END: ("SAVE_END", 1, "Save capture end (arg: group_idx)"),
113→ RegexOpCode.SAVE_RESET: ("SAVE_RESET", 2, "Reset captures (args: start_idx, end_idx)"),
114→
115→ RegexOpCode.BACKREF: ("BACKREF", 1, "Match captured group (arg: group_idx)"),
116→ RegexOpCode.BACKREF_I: ("BACKREF_I", 1, "Match captured group case-insensitive"),
117→
118→ RegexOpCode.LOOKAHEAD: ("LOOKAHEAD", 1, "Positive lookahead (arg: end_offset)"),
119→ RegexOpCode.LOOKAHEAD_NEG: ("LOOKAHEAD_NEG", 1, "Negative lookahead (arg: end_offset)"),
120→ RegexOpCode.LOOKAHEAD_END: ("LOOKAHEAD_END", 0, "End of lookahead"),
121→
122→ RegexOpCode.LOOKBEHIND: ("LOOKBEHIND", 1, "Positive lookbehind (arg: end_offset)"),
123→ RegexOpCode.LOOKBEHIND_NEG: ("LOOKBEHIND_NEG", 1, "Negative lookbehind (arg: end_offset)"),
124→ RegexOpCode.LOOKBEHIND_END: ("LOOKBEHIND_END", 0, "End of lookbehind"),
125→
126→ RegexOpCode.SET_POS: ("SET_POS", 1, "Save position to register (arg: reg_idx)"),
127→ RegexOpCode.CHECK_ADVANCE: ("CHECK_ADVANCE", 1, "Check position advanced (arg: reg_idx)"),
128→
129→ RegexOpCode.MATCH: ("MATCH", 0, "Successful match"),
130→}
131→
132→
133→def disassemble(bytecode: list) -> str:
134→ """
135→ Disassemble bytecode to human-readable format.
136→
137→ Args:
138→ bytecode: List of (opcode, *args) tuples
139→
140→ Returns:
141→ Disassembled string representation
142→ """
143→ lines = []
144→ for i, instr in enumerate(bytecode):
145→ opcode = instr[0]
146→ args = instr[1:] if len(instr) > 1 else []
147→ info = OPCODE_INFO.get(opcode, (str(opcode), 0, "Unknown"))
148→ name = info[0]
149→
150→ if args:
151→ arg_str = ", ".join(repr(a) for a in args)
152→ lines.append(f"{i:4d}: {name} {arg_str}")
153→ else:
154→ lines.append(f"{i:4d}: {name}")
155→
156→ return "\n".join(lines)
157→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
The opcodes are defined. Now let me check the VM to see if lookbehind is implemented there:
{
"-C": 3,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/regex/vm.py",
"pattern": "LOOKBEHIND"
}523- # Successfully matched lookahead content 524- return MatchResult([], 0, "") # Special marker 525- 526: elif opcode == Op.LOOKBEHIND: 527- end_offset = instr[1] 528- # Lookbehind is complex - for now, simplified implementation 529- # Would need to try matching backwards -- 532- return None 533- pc, sp, captures, registers = self._backtrack(stack) 534- 535: elif opcode == Op.LOOKBEHIND_NEG: 536- end_offset = instr[1] 537- # Placeholder 538- pc = end_offset 539- 540: elif opcode == Op.LOOKBEHIND_END: 541- return MatchResult([], 0, "") 542- 543- elif opcode == Op.SET_POS:
I see - the lookbehind is not fully implemented. Lines 526-541 show placeholder implementations. Let me read the full VM to understand how lookahead is implemented, so I can implement lookbehind properly:
I see the lookbehind is not fully implemented. Let me check how lookahead is implemented to understand the pattern:
{
"-C": 10,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/regex/vm.py",
"pattern": "LOOKAHEAD"
}474- continue
475-
476- if string[sp:sp + len(captured)].lower() == captured.lower():
477- sp += len(captured)
478- pc += 1
479- else:
480- if not stack:
481- return None
482- pc, sp, captures, registers = self._backtrack(stack)
483-
484: elif opcode == Op.LOOKAHEAD:
485- end_offset = instr[1]
486- # Save current state and try to match lookahead
487- saved_sp = sp
488- saved_captures = [c.copy() for c in captures]
489-
490- # Create sub-execution for lookahead
491- la_result = self._execute_lookahead(string, sp, pc + 1, end_offset)
492-
493- if la_result:
494- # Lookahead succeeded - restore position and continue after
495- sp = saved_sp
496- captures = saved_captures
497- pc = end_offset
498- else:
499- # Lookahead failed
500- if not stack:
501- return None
502- pc, sp, captures, registers = self._backtrack(stack)
503-
504: elif opcode == Op.LOOKAHEAD_NEG:
505- end_offset = instr[1]
506- saved_sp = sp
507- saved_captures = [c.copy() for c in captures]
508-
509- la_result = self._execute_lookahead(string, sp, pc + 1, end_offset)
510-
511- if not la_result:
512- # Negative lookahead succeeded (inner didn't match)
513- sp = saved_sp
514- captures = saved_captures
515- pc = end_offset
516- else:
517- # Negative lookahead failed (inner matched)
518- if not stack:
519- return None
520- pc, sp, captures, registers = self._backtrack(stack)
521-
522: elif opcode == Op.LOOKAHEAD_END:
523- # Successfully matched lookahead content
524- return MatchResult([], 0, "") # Special marker
525-
526- elif opcode == Op.LOOKBEHIND:
527- end_offset = instr[1]
528- # Lookbehind is complex - for now, simplified implementation
529- # Would need to try matching backwards
530- # This is a placeholder that always fails
531- if not stack:
532- return None
--
601-
602- if len(stack) > self.stack_limit:
603- raise RegexStackOverflow("Regex stack overflow")
604-
605- if pc >= end_pc:
606- return False
607-
608- instr = self.bytecode[pc]
609- opcode = instr[0]
610-
611: if opcode == Op.LOOKAHEAD_END:
612- return True # Lookahead content matched
613-
614- # Reuse main execution logic for other opcodes
615- # This is simplified - in production would share more code
616- if opcode == Op.CHAR:
617- char_code = instr[1]
618- if sp >= len(string):
619- if not stack:
620- return False
621- pc, sp, captures, registers = stack.pop()The user wants me to move the passing C implementation tests to a separate tests/compat folder instead of tests/basic. Let me revert my change and move them correctly.First let me check the current state:
mkdir -p /home/user/mquickjs-python/tests/compat && mv /home/user/mquickjs-python/tests/basic/test_loop.js /home/user/mquickjs-python/tests/compat/ && mv /home/user/mquickjs-python/tests/basic/test_closure.js /home/user/mquickjs-python/tests/compat/
Now I need to update test_js_basic.py to add a new test function for tests/compat:
1→"""
2→Parameterized pytest tests for JavaScript files.
3→
4→- Each .js file in tests/basic/ is run as a test case (should pass)
5→- Each .js file in tests/ (original mquickjs tests) is run with xfail (expected to fail)
6→"""
7→from pathlib import Path
8→
9→import pytest
10→
11→from mquickjs_python import JSContext
12→
13→
14→def get_basic_test_files():
15→ """Discover all .js files in tests/basic/ directory."""
16→ basic_dir = Path(__file__).parent / "basic"
17→ if not basic_dir.exists():
18→ return []
19→ js_files = sorted(basic_dir.glob("*.js"))
20→ return [(f.name, f) for f in js_files]
21→
22→
23→def get_mquickjs_test_files():
24→ """Discover original mquickjs .js test files in tests/ directory."""
25→ tests_dir = Path(__file__).parent
26→ # Get all .js files directly in tests/ (not in subdirectories)
27→ js_files = sorted(tests_dir.glob("*.js"))
28→ return [(f.name, f) for f in js_files]
29→
30→
31→@pytest.mark.parametrize(
32→ "name,path",
33→ get_basic_test_files(),
34→ ids=lambda x: x if isinstance(x, str) else None,
35→)
36→def test_basic_js(name: str, path: Path):
37→ """Run a basic JavaScript test file."""
38→ source = path.read_text(encoding="utf-8")
39→ ctx = JSContext()
40→ # Execute the script - if it throws, the test fails
41→ ctx.eval(source)
42→
43→
44→@pytest.mark.parametrize(
45→ "name,path",
46→ get_mquickjs_test_files(),
47→ ids=lambda x: x if isinstance(x, str) else None,
48→)
49→@pytest.mark.xfail(reason="Original mquickjs tests - not yet passing")
50→def test_mquickjs_js(name: str, path: Path):
51→ """Run an original mquickjs JavaScript test file.
52→
53→ These tests are expected to fail until the VM is complete.
54→ Watch for xfail tests that start passing!
55→ """
56→ source = path.read_text(encoding="utf-8")
57→ ctx = JSContext(time_limit=2.0) # Timeout to avoid infinite loops
58→ # Execute the script - if it throws, the test fails
59→ ctx.eval(source)
60→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
"""
Parameterized pytest tests for JavaScript files.
- Each .js file in tests/basic/ is run as a test case (should pass)
- Each .js file in tests/ (original mquickjs tests) is run with xfail (expected to fail)
"""
from pathlib import Path
import pytest
from mquickjs_python import JSContext
def get_basic_test_files():
"""Discover all .js files in tests/basic/ directory."""
basic_dir = Path(__file__).parent / "basic"
if not basic_dir.exists():
return []
js_files = sorted(basic_dir.glob("*.js"))
return [(f.name, f) for f in js_files]
def get_mquickjs_test_files():
"""Discover original mquickjs .js test files in tests/ directory."""
tests_dir = Path(__file__).parent
# Get all .js files directly in tests/ (not in subdirectories)
js_files = sorted(tests_dir.glob("*.js"))
return [(f.name, f) for f in js_files]
@pytest.mark.parametrize(
"name,path",
get_basic_test_files(),
ids=lambda x: x if isinstance(x, str) else None,
)
def test_basic_js(name: str, path: Path):
"""Run a basic JavaScript test file."""
source = path.read_text(encoding="utf-8")
ctx = JSContext()
# Execute the script - if it throws, the test fails
ctx.eval(source)
@pytest.mark.parametrize(
"name,path",
get_mquickjs_test_files(),
ids=lambda x: x if isinstance(x, str) else None,
)
@pytest.mark.xfail(reason="Original mquickjs tests - not yet passing")
def test_mquickjs_js(name: str, path: Path):
"""Run an original mquickjs JavaScript test file.
These tests are expected to fail until the VM is complete.
Watch for xfail tests that start passing!
"""
source = path.read_text(encoding="utf-8")
ctx = JSContext(time_limit=2.0) # Timeout to avoid infinite loops
# Execute the script - if it throws, the test fails
ctx.eval(source)"""
Parameterized pytest tests for JavaScript files.
- Each .js file in tests/basic/ is run as a test case (should pass)
- Each .js file in tests/compat/ are passing original mquickjs tests
- Each .js file in tests/ (original mquickjs tests) is run with xfail (expected to fail)
"""
from pathlib import Path
import pytest
from mquickjs_python import JSContext
def get_basic_test_files():
"""Discover all .js files in tests/basic/ directory."""
basic_dir = Path(__file__).parent / "basic"
if not basic_dir.exists():
return []
js_files = sorted(basic_dir.glob("*.js"))
return [(f.name, f) for f in js_files]
def get_compat_test_files():
"""Discover passing original mquickjs .js test files in tests/compat/ directory."""
compat_dir = Path(__file__).parent / "compat"
if not compat_dir.exists():
return []
js_files = sorted(compat_dir.glob("*.js"))
return [(f.name, f) for f in js_files]
def get_mquickjs_test_files():
"""Discover original mquickjs .js test files in tests/ directory."""
tests_dir = Path(__file__).parent
# Get all .js files directly in tests/ (not in subdirectories)
js_files = sorted(tests_dir.glob("*.js"))
return [(f.name, f) for f in js_files]
@pytest.mark.parametrize(
"name,path",
get_basic_test_files(),
ids=lambda x: x if isinstance(x, str) else None,
)
def test_basic_js(name: str, path: Path):
"""Run a basic JavaScript test file."""
source = path.read_text(encoding="utf-8")
ctx = JSContext()
# Execute the script - if it throws, the test fails
ctx.eval(source)
@pytest.mark.parametrize(
"name,path",
get_compat_test_files(),
ids=lambda x: x if isinstance(x, str) else None,
)
def test_compat_js(name: str, path: Path):
"""Run a passing original mquickjs JavaScript test file.
These are tests from the original C mquickjs implementation
that now pass in our Python implementation.
"""
source = path.read_text(encoding="utf-8")
ctx = JSContext(time_limit=2.0)
# Execute the script - if it throws, the test fails
ctx.eval(source)
@pytest.mark.parametrize(
"name,path",
get_mquickjs_test_files(),
ids=lambda x: x if isinstance(x, str) else None,
)
@pytest.mark.xfail(reason="Original mquickjs tests - not yet passing")
def test_mquickjs_js(name: str, path: Path):
"""Run an original mquickjs JavaScript test file.
These tests are expected to fail until the VM is complete.
Watch for xfail tests that start passing!
"""
source = path.read_text(encoding="utf-8")
ctx = JSContext(time_limit=2.0) # Timeout to avoid infinite loops
# Execute the script - if it throws, the test fails
ctx.eval(source)The file /home/user/mquickjs-python/tests/test_js_basic.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
1→"""
2→Parameterized pytest tests for JavaScript files.
3→
4→- Each .js file in tests/basic/ is run as a test case (should pass)
5→- Each .js file in tests/compat/ are passing original mquickjs tests
6→- Each .js file in tests/ (original mquickjs tests) is run with xfail (expected to fail)
7→"""
8→from pathlib import Path
9→
10→import pytest
11→
12→from mquickjs_python import JSContext
13→
14→
15→def get_basic_test_files():
16→ """Discover all .js files in tests/basic/ directory."""
17→ basic_dir = Path(__file__).parent / "basic"
18→ if not basic_dir.exists():
19→ return []
20→ js_files = sorted(basic_dir.glob("*.js"))
21→ return [(f.name, f) for f in js_files]
22→
23→
24→def get_compat_test_files():
25→ """Discover passing original mquickjs .js test files in tests/compat/ directory."""
26→ compat_dir = Path(__file__).parent / "compat"
27→ if not compat_dir.exists():
28→ return []
29→ js_files = sorted(compat_dir.glob("*.js"))
30→ return [(f.name, f) for f in js_files]
31→
32→
33→def get_mquickjs_test_files():
34→ """Discover original mquickjs .js test files in tests/ directory."""
35→ tests_dir = Path(__file__).parent
36→ # Get all .js files directly in tests/ (not in subdirectories)
37→ js_files = sorted(tests_dir.glob("*.js"))
38→ return [(f.name, f) for f in js_files]
39→
40→
41→@pytest.mark.parametrize(
42→ "name,path",
43→ get_basic_test_files(),
44→ ids=lambda x: x if isinstance(x, str) else None,
45→)
46→def test_basic_js(name: str, path: Path):
47→ """Run a basic JavaScript test file."""
48→ source = path.read_text(encoding="utf-8")
49→ ctx = JSContext()
50→ # Execute the script - if it throws, the test fails
51→ ctx.eval(source)
52→
53→
54→@pytest.mark.parametrize(
55→ "name,path",
56→ get_compat_test_files(),
57→ ids=lambda x: x if isinstance(x, str) else None,
58→)
59→def test_compat_js(name: str, path: Path):
60→ """Run a passing original mquickjs JavaScript test file.
61→
62→ These are tests from the original C mquickjs implementation
63→ that now pass in our Python implementation.
64→ """
65→ source = path.read_text(encoding="utf-8")
66→ ctx = JSContext(time_limit=2.0)
67→ # Execute the script - if it throws, the test fails
68→ ctx.eval(source)
69→
70→
71→@pytest.mark.parametrize(
72→ "name,path",
73→ get_mquickjs_test_files(),
74→ ids=lambda x: x if isinstance(x, str) else None,
75→)
76→@pytest.mark.xfail(reason="Original mquickjs tests - not yet passing")
77→def test_mquickjs_js(name: str, path: Path):
78→ """Run an original mquickjs JavaScript test file.
79→
80→ These tests are expected to fail until the VM is complete.
81→ Watch for xfail tests that start passing!
82→ """
83→ source = path.read_text(encoding="utf-8")
84→ ctx = JSContext(time_limit=2.0) # Timeout to avoid infinite loops
85→ # Execute the script - if it throws, the test fails
86→ ctx.eval(source)
87→tests/test_js_basic.py::test_basic_js[test_loop_switch.js-path8] PASSED [ 34%] tests/test_js_basic.py::test_basic_js[test_loop_switch2.js-path9] PASSED [ 38%] tests/test_js_basic.py::test_basic_js[test_loop_try5.js-path10] PASSED [ 42%] tests/test_js_basic.py::test_basic_js[test_loop_while.js-path11] PASSED [ 46%] tests/test_js_basic.py::test_basic_js[test_math.js-path12] PASSED [ 50%] tests/test_js_basic.py::test_basic_js[test_number_date.js-path13] PASSED [ 53%] tests/test_js_basic.py::test_basic_js[test_object_methods.js-path14] PASSED [ 57%] tests/test_js_basic.py::test_basic_js[test_regexp.js-path15] PASSED [ 61%] tests/test_js_basic.py::test_basic_js[test_string_methods.js-path16] PASSED [ 65%] tests/test_js_basic.py::test_basic_js[test_try_catch.js-path17] PASSED [ 69%] tests/test_js_basic.py::test_basic_js[test_try_catch_simple.js-path18] PASSED [ 73%] tests/test_js_basic.py::test_compat_js[test_closure.js-path0] PASSED [ 76%] tests/test_js_basic.py::test_compat_js[test_loop.js-path1] PASSED [ 80%] tests/test_js_basic.py::test_mquickjs_js[mandelbrot.js-path0] XFAIL [ 84%] tests/test_js_basic.py::test_mquickjs_js[microbench.js-path1] XFAIL [ 88%] tests/test_js_basic.py::test_mquickjs_js[test_builtin.js-path2] XFAIL [ 92%] tests/test_js_basic.py::test_mquickjs_js[test_language.js-path3] XFAIL [ 96%] tests/test_js_basic.py::test_mquickjs_js[test_rect.js-path4] XFAIL (...) [100%] ======================== 21 passed, 5 xfailed in 2.92s =========================
git add -A && git commit -m "Organize passing mquickjs tests into tests/compat/ directory"
3 files changed, 27 insertions(+)
rename tests/{basic => compat}/test_closure.js (100%)
rename tests/{basic => compat}/test_loop.js (100%)Now let me continue implementing lookbehind. Let me read more of the VM to understand how to implement it:
Now let me implement regex lookbehind properly. Let me look at the VM's lookahead implementation:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/regex/vm.py",
"limit": 80,
"offset": 560
} 560→ elif opcode == Op.MATCH:
561→ # Successful match!
562→ groups = []
563→ for start, end in captures:
564→ if start == -1 or end == -1:
565→ groups.append(None)
566→ else:
567→ groups.append(string[start:end])
568→ return MatchResult(groups, captures[0][0], string)
569→
570→ else:
571→ raise RuntimeError(f"Unknown opcode: {opcode}")
572→
573→ def _backtrack(self, stack: List[Tuple]) -> Tuple:
574→ """Pop and return state from backtrack stack."""
575→ return stack.pop()
576→
577→ def _is_word_boundary(self, string: str, pos: int) -> bool:
578→ """Check if position is at a word boundary."""
579→ def is_word_char(ch: str) -> bool:
580→ return ch.isalnum() or ch == '_'
581→
582→ before = pos > 0 and is_word_char(string[pos - 1])
583→ after = pos < len(string) and is_word_char(string[pos])
584→ return before != after
585→
586→ def _execute_lookahead(self, string: str, start_pos: int, start_pc: int, end_pc: int) -> bool:
587→ """Execute bytecode for lookahead assertion."""
588→ # Simple recursive call with limited bytecode range
589→ pc = start_pc
590→ sp = start_pos
591→ captures = [[-1, -1] for _ in range(self.capture_count)]
592→ registers: List[int] = []
593→ stack: List[Tuple] = []
594→ step_count = 0
595→
596→ while True:
597→ step_count += 1
598→ if step_count % self.poll_interval == 0:
599→ if self.poll_callback and self.poll_callback():
600→ raise RegexTimeoutError("Regex execution timed out")
601→
602→ if len(stack) > self.stack_limit:
603→ raise RegexStackOverflow("Regex stack overflow")
604→
605→ if pc >= end_pc:
606→ return False
607→
608→ instr = self.bytecode[pc]
609→ opcode = instr[0]
610→
611→ if opcode == Op.LOOKAHEAD_END:
612→ return True # Lookahead content matched
613→
614→ # Reuse main execution logic for other opcodes
615→ # This is simplified - in production would share more code
616→ if opcode == Op.CHAR:
617→ char_code = instr[1]
618→ if sp >= len(string):
619→ if not stack:
620→ return False
621→ pc, sp, captures, registers = stack.pop()
622→ continue
623→ ch = string[sp]
624→ if self.ignorecase:
625→ match = ord(ch.lower()) == char_code or ord(ch.upper()) == char_code
626→ else:
627→ match = ord(ch) == char_code
628→ if match:
629→ sp += 1
630→ pc += 1
631→ else:
632→ if not stack:
633→ return False
634→ pc, sp, captures, registers = stack.pop()
635→
636→ elif opcode == Op.DOT:
637→ if sp >= len(string) or string[sp] == '\n':
638→ if not stack:
639→ return False
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see. The lookahead creates a sub-execution context that matches forward from the current position. For lookbehind, I need to:1. Create a sub-execution context that matches BACKWARDS from the current position 2. Try different starting positions backwards until one matchesThe challenge is that lookbehind patterns have a fixed length in JavaScript (mostly). Let me implement a simple version that:1. Calculates the length of the lookbehind pattern (if possible) 2. Tries to match from position - length3. Or if variable length, tries all possible starting positions
Let me look at what the current lookbehind code does:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/regex/vm.py",
"limit": 50,
"offset": 520
}520→ pc, sp, captures, registers = self._backtrack(stack) 521→ 522→ elif opcode == Op.LOOKAHEAD_END: 523→ # Successfully matched lookahead content 524→ return MatchResult([], 0, "") # Special marker 525→ 526→ elif opcode == Op.LOOKBEHIND: 527→ end_offset = instr[1] 528→ # Lookbehind is complex - for now, simplified implementation 529→ # Would need to try matching backwards 530→ # This is a placeholder that always fails 531→ if not stack: 532→ return None 533→ pc, sp, captures, registers = self._backtrack(stack) 534→ 535→ elif opcode == Op.LOOKBEHIND_NEG: 536→ end_offset = instr[1] 537→ # Placeholder 538→ pc = end_offset 539→ 540→ elif opcode == Op.LOOKBEHIND_END: 541→ return MatchResult([], 0, "") 542→ 543→ elif opcode == Op.SET_POS: 544→ reg_idx = instr[1] 545→ while len(registers) <= reg_idx: 546→ registers.append(-1) 547→ registers[reg_idx] = sp 548→ pc += 1 549→ 550→ elif opcode == Op.CHECK_ADVANCE: 551→ reg_idx = instr[1] 552→ if reg_idx < len(registers) and registers[reg_idx] == sp: 553→ # Position didn't advance - fail to prevent infinite loop 554→ if not stack: 555→ return None 556→ pc, sp, captures, registers = self._backtrack(stack) 557→ continue 558→ pc += 1 559→ 560→ elif opcode == Op.MATCH: 561→ # Successful match! 562→ groups = [] 563→ for start, end in captures: 564→ if start == -1 or end == -1: 565→ groups.append(None) 566→ else: 567→ groups.append(string[start:end]) 568→ return MatchResult(groups, captures[0][0], string) 569→ <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
The current implementation is a placeholder. I need to implement a proper lookbehind.For lookbehind (?<=foo)bar:1. At position sp, we want to check if "foo" appears BEFORE this position 2. So we need to try matching "foo" starting at position sp-len(foo) and ending at spThe challenge is that the lookbehind pattern might have variable length (quantifiers). For a proper implementation, I'd need to:1. Calculate possible pattern lengths2. For each possible length L from 1 to current position: - Try to match the lookbehind pattern starting at position sp-L - If it matches exactly L characters ending at position sp, successLet me implement a simplified version that works for fixed-length patterns:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/regex/vm.py",
"limit": 60,
"offset": 1
} 1→"""
2→Regex bytecode VM.
3→
4→Executes regex bytecode with:
5→- Explicit backtracking stack
6→- Timeout integration via polling
7→- Memory limits (stack size)
8→- ReDoS protection
9→"""
10→
11→from typing import List, Tuple, Optional, Callable
12→from .opcodes import RegexOpCode as Op
13→
14→
15→class RegexTimeoutError(Exception):
16→ """Raised when regex execution times out."""
17→ pass
18→
19→
20→class RegexStackOverflow(Exception):
21→ """Raised when regex stack limit is exceeded."""
22→ pass
23→
24→
25→class MatchResult:
26→ """Result of a successful regex match."""
27→
28→ def __init__(self, groups: List[Optional[str]], index: int, input_str: str):
29→ self._groups = groups
30→ self.index = index
31→ self.input = input_str
32→
33→ def __getitem__(self, idx: int) -> Optional[str]:
34→ if idx < 0 or idx >= len(self._groups):
35→ return None
36→ return self._groups[idx]
37→
38→ def __len__(self) -> int:
39→ return len(self._groups)
40→
41→ def group(self, idx: int = 0) -> Optional[str]:
42→ return self[idx]
43→
44→ def groups(self) -> Tuple[Optional[str], ...]:
45→ return tuple(self._groups[1:]) # Exclude group 0
46→
47→ def __repr__(self):
48→ return f"MatchResult({self._groups!r}, index={self.index})"
49→
50→
51→class RegexVM:
52→ """
53→ Regex bytecode virtual machine.
54→
55→ Implements NFA-based matching with explicit backtracking stack.
56→ """
57→
58→ # Default limits
59→ DEFAULT_STACK_LIMIT = 10000
60→ DEFAULT_POLL_INTERVAL = 100
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
Let me read more of the VM to see where to add the lookbehind execution method and understand the structure:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/regex/vm.py",
"limit": 150,
"offset": 570
} 570→ else:
571→ raise RuntimeError(f"Unknown opcode: {opcode}")
572→
573→ def _backtrack(self, stack: List[Tuple]) -> Tuple:
574→ """Pop and return state from backtrack stack."""
575→ return stack.pop()
576→
577→ def _is_word_boundary(self, string: str, pos: int) -> bool:
578→ """Check if position is at a word boundary."""
579→ def is_word_char(ch: str) -> bool:
580→ return ch.isalnum() or ch == '_'
581→
582→ before = pos > 0 and is_word_char(string[pos - 1])
583→ after = pos < len(string) and is_word_char(string[pos])
584→ return before != after
585→
586→ def _execute_lookahead(self, string: str, start_pos: int, start_pc: int, end_pc: int) -> bool:
587→ """Execute bytecode for lookahead assertion."""
588→ # Simple recursive call with limited bytecode range
589→ pc = start_pc
590→ sp = start_pos
591→ captures = [[-1, -1] for _ in range(self.capture_count)]
592→ registers: List[int] = []
593→ stack: List[Tuple] = []
594→ step_count = 0
595→
596→ while True:
597→ step_count += 1
598→ if step_count % self.poll_interval == 0:
599→ if self.poll_callback and self.poll_callback():
600→ raise RegexTimeoutError("Regex execution timed out")
601→
602→ if len(stack) > self.stack_limit:
603→ raise RegexStackOverflow("Regex stack overflow")
604→
605→ if pc >= end_pc:
606→ return False
607→
608→ instr = self.bytecode[pc]
609→ opcode = instr[0]
610→
611→ if opcode == Op.LOOKAHEAD_END:
612→ return True # Lookahead content matched
613→
614→ # Reuse main execution logic for other opcodes
615→ # This is simplified - in production would share more code
616→ if opcode == Op.CHAR:
617→ char_code = instr[1]
618→ if sp >= len(string):
619→ if not stack:
620→ return False
621→ pc, sp, captures, registers = stack.pop()
622→ continue
623→ ch = string[sp]
624→ if self.ignorecase:
625→ match = ord(ch.lower()) == char_code or ord(ch.upper()) == char_code
626→ else:
627→ match = ord(ch) == char_code
628→ if match:
629→ sp += 1
630→ pc += 1
631→ else:
632→ if not stack:
633→ return False
634→ pc, sp, captures, registers = stack.pop()
635→
636→ elif opcode == Op.DOT:
637→ if sp >= len(string) or string[sp] == '\n':
638→ if not stack:
639→ return False
640→ pc, sp, captures, registers = stack.pop()
641→ continue
642→ sp += 1
643→ pc += 1
644→
645→ elif opcode == Op.SPLIT_FIRST:
646→ alt_pc = instr[1]
647→ stack.append((alt_pc, sp, [c.copy() for c in captures], registers.copy()))
648→ pc += 1
649→
650→ elif opcode == Op.SPLIT_NEXT:
651→ alt_pc = instr[1]
652→ stack.append((pc + 1, sp, [c.copy() for c in captures], registers.copy()))
653→ pc = alt_pc
654→
655→ elif opcode == Op.JUMP:
656→ pc = instr[1]
657→
658→ elif opcode == Op.MATCH:
659→ return True
660→
661→ else:
662→ # Handle other opcodes similarly to main loop
663→ pc += 1
664→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
The file ends at line 663, so _execute_lookahead is the last method. Let me implement lookbehind. For lookbehind, I need to:1. Try to match the pattern starting at different positions BEFORE the current position
2. Check if the match ends exactly at the current positionLet me add a new method _execute_lookbehind and update the LOOKBEHIND opcode handling:
elif opcode == Op.LOOKBEHIND:
end_offset = instr[1]
# Lookbehind is complex - for now, simplified implementation
# Would need to try matching backwards
# This is a placeholder that always fails
if not stack:
return None
pc, sp, captures, registers = self._backtrack(stack)
elif opcode == Op.LOOKBEHIND_NEG:
end_offset = instr[1]
# Placeholder
pc = end_offset
elif opcode == Op.LOOKBEHIND_END:
return MatchResult([], 0, "") elif opcode == Op.LOOKBEHIND:
end_offset = instr[1]
saved_sp = sp
saved_captures = [c.copy() for c in captures]
# Try lookbehind - match pattern ending at current position
lb_result = self._execute_lookbehind(string, sp, pc + 1, end_offset)
if lb_result:
# Lookbehind succeeded - restore position and continue after
sp = saved_sp
captures = saved_captures
pc = end_offset
else:
# Lookbehind failed
if not stack:
return None
pc, sp, captures, registers = self._backtrack(stack)
elif opcode == Op.LOOKBEHIND_NEG:
end_offset = instr[1]
saved_sp = sp
saved_captures = [c.copy() for c in captures]
lb_result = self._execute_lookbehind(string, sp, pc + 1, end_offset)
if not lb_result:
# Negative lookbehind succeeded (inner didn't match)
sp = saved_sp
captures = saved_captures
pc = end_offset
else:
# Negative lookbehind failed (inner matched)
if not stack:
return None
pc, sp, captures, registers = self._backtrack(stack)
elif opcode == Op.LOOKBEHIND_END:
return MatchResult([], 0, "") # Special markerThe file /home/user/mquickjs-python/src/mquickjs_python/regex/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 522→ elif opcode == Op.LOOKAHEAD_END: 523→ # Successfully matched lookahead content 524→ return MatchResult([], 0, "") # Special marker 525→ 526→ elif opcode == Op.LOOKBEHIND: 527→ end_offset = instr[1] 528→ saved_sp = sp 529→ saved_captures = [c.copy() for c in captures] 530→ 531→ # Try lookbehind - match pattern ending at current position 532→ lb_result = self._execute_lookbehind(string, sp, pc + 1, end_offset) 533→ 534→ if lb_result: 535→ # Lookbehind succeeded - restore position and continue after 536→ sp = saved_sp 537→ captures = saved_captures 538→ pc = end_offset 539→ else: 540→ # Lookbehind failed 541→ if not stack: 542→ return None 543→ pc, sp, captures, registers = self._backtrack(stack) 544→ 545→ elif opcode == Op.LOOKBEHIND_NEG: 546→ end_offset = instr[1] 547→ saved_sp = sp 548→ saved_captures = [c.copy() for c in captures] 549→ 550→ lb_result = self._execute_lookbehind(string, sp, pc + 1, end_offset) 551→ 552→ if not lb_result: 553→ # Negative lookbehind succeeded (inner didn't match) 554→ sp = saved_sp 555→ captures = saved_captures 556→ pc = end_offset 557→ else: 558→ # Negative lookbehind failed (inner matched) 559→ if not stack: 560→ return None 561→ pc, sp, captures, registers = self._backtrack(stack) 562→ 563→ elif opcode == Op.LOOKBEHIND_END: 564→ return MatchResult([], 0, "") # Special marker 565→ 566→ elif opcode == Op.SET_POS: 567→ reg_idx = instr[1] 568→ while len(registers) <= reg_idx:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/regex/vm.py",
"limit": 30,
"offset": 675
}675→ stack.append((pc + 1, sp, [c.copy() for c in captures], registers.copy())) 676→ pc = alt_pc 677→ 678→ elif opcode == Op.JUMP: 679→ pc = instr[1] 680→ 681→ elif opcode == Op.MATCH: 682→ return True 683→ 684→ else: 685→ # Handle other opcodes similarly to main loop 686→ pc += 1 687→ <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
The file ends at line 687, so I need to add the _execute_lookbehind method after line 686. Let me add it:
elif opcode == Op.MATCH:
return True
else:
# Handle other opcodes similarly to main loop
pc += 1
elif opcode == Op.MATCH:
return True
else:
# Handle other opcodes similarly to main loop
pc += 1
def _execute_lookbehind(self, string: str, end_pos: int, start_pc: int, end_pc: int) -> bool:
"""Execute bytecode for lookbehind assertion.
Lookbehind matches if the pattern matches text ending at end_pos.
We try all possible start positions backwards from end_pos.
"""
# Try all possible starting positions from 0 to end_pos
# We want the pattern to match and end exactly at end_pos
for start_pos in range(end_pos, -1, -1):
result = self._try_lookbehind_at(string, start_pos, end_pos, start_pc, end_pc)
if result:
return True
return False
def _try_lookbehind_at(self, string: str, start_pos: int, end_pos: int,
start_pc: int, end_pc: int) -> bool:
"""Try to match lookbehind pattern from start_pos, checking it ends at end_pos."""
pc = start_pc
sp = start_pos
captures = [[-1, -1] for _ in range(self.capture_count)]
registers: List[int] = []
stack: List[Tuple] = []
step_count = 0
while True:
step_count += 1
if step_count % self.poll_interval == 0:
if self.poll_callback and self.poll_callback():
raise RegexTimeoutError("Regex execution timed out")
if len(stack) > self.stack_limit:
raise RegexStackOverflow("Regex stack overflow")
if pc >= end_pc:
return False
instr = self.bytecode[pc]
opcode = instr[0]
if opcode == Op.LOOKBEHIND_END:
# Check if we ended exactly at the target position
return sp == end_pos
if opcode == Op.CHAR:
char_code = instr[1]
if sp >= len(string):
if not stack:
return False
pc, sp, captures, registers = stack.pop()
continue
ch = string[sp]
if self.ignorecase:
match = ord(ch.lower()) == char_code or ord(ch.upper()) == char_code
else:
match = ord(ch) == char_code
if match:
sp += 1
pc += 1
else:
if not stack:
return False
pc, sp, captures, registers = stack.pop()
elif opcode == Op.DOT:
if sp >= len(string) or string[sp] == '\n':
if not stack:
return False
pc, sp, captures, registers = stack.pop()
continue
sp += 1
pc += 1
elif opcode == Op.DIGIT:
if sp >= len(string) or not string[sp].isdigit():
if not stack:
return False
pc, sp, captures, registers = stack.pop()
continue
sp += 1
pc += 1
elif opcode == Op.WORD:
if sp >= len(string):
if not stack:
return False
pc, sp, captures, registers = stack.pop()
continue
ch = string[sp]
if ch.isalnum() or ch == '_':
sp += 1
pc += 1
else:
if not stack:
return False
pc, sp, captures, registers = stack.pop()
elif opcode == Op.SPLIT_FIRST:
alt_pc = instr[1]
stack.append((alt_pc, sp, [c.copy() for c in captures], registers.copy()))
pc += 1
elif opcode == Op.SPLIT_NEXT:
alt_pc = instr[1]
stack.append((pc + 1, sp, [c.copy() for c in captures], registers.copy()))
pc = alt_pc
elif opcode == Op.JUMP:
pc = instr[1]
elif opcode == Op.MATCH:
# Check if we ended exactly at the target position
return sp == end_pos
else:
# Handle other opcodes - advance pc
pc += 1
The file /home/user/mquickjs-python/src/mquickjs_python/regex/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
677→
678→ elif opcode == Op.JUMP:
679→ pc = instr[1]
680→
681→ elif opcode == Op.MATCH:
682→ return True
683→
684→ else:
685→ # Handle other opcodes similarly to main loop
686→ pc += 1
687→
688→ def _execute_lookbehind(self, string: str, end_pos: int, start_pc: int, end_pc: int) -> bool:
689→ """Execute bytecode for lookbehind assertion.
690→
691→ Lookbehind matches if the pattern matches text ending at end_pos.
692→ We try all possible start positions backwards from end_pos.
693→ """
694→ # Try all possible starting positions from 0 to end_pos
695→ # We want the pattern to match and end exactly at end_pos
696→ for start_pos in range(end_pos, -1, -1):
697→ result = self._try_lookbehind_at(string, start_pos, end_pos, start_pc, end_pc)
698→ if result:
699→ return True
700→ return False
701→
702→ def _try_lookbehind_at(self, string: str, start_pos: int, end_pos: int,
703→ start_pc: int, end_pc: int) -> bool:
704→ """Try to match lookbehind pattern from start_pos, checking it ends at end_pos."""
705→ pc = start_pc
706→ sp = start_pos
707→ captures = [[-1, -1] for _ in range(self.capture_count)]
708→ registers: List[int] = []
709→ stack: List[Tuple] = []
710→ step_count = 0
711→
712→ while True:
713→ step_count += 1
714→ if step_count % self.poll_interval == 0:
715→ if self.poll_callback and self.poll_callback():
716→ raise RegexTimeoutError("Regex execution timed out")
717→
718→ if len(stack) > self.stack_limit:
719→ raise RegexStackOverflow("Regex stack overflow")
720→
721→ if pc >= end_pc:
722→ return False
723→
724→ instr = self.bytecode[pc]
725→ opcode = instr[0]
726→
727→ if opcode == Op.LOOKBEHIND_END:
728→ # Check if we ended exactly at the target position
729→ return sp == end_pos
730→
731→ if opcode == Op.CHAR:
732→ char_code = instr[1]
733→ if sp >= len(string):
734→ if not stack:
735→ return False
736→ pc, sp, captures, registers = stack.pop()
737→ continue
738→ ch = string[sp]
739→ if self.ignorecase:
740→ match = ord(ch.lower()) == char_code or ord(ch.upper()) == char_code
741→ else:
742→ match = ord(ch) == char_code
743→ if match:
744→ sp += 1
745→ pc += 1
746→ else:
747→ if not stack:
748→ return False
749→ pc, sp, captures, registers = stack.pop()
750→
751→ elif opcode == Op.DOT:
752→ if sp >= len(string) or string[sp] == '\n':
753→ if not stack:
754→ return False
755→ pc, sp, captures, registers = stack.pop()
756→ continue
757→ sp += 1
758→ pc += 1
759→
760→ elif opcode == Op.DIGIT:
761→ if sp >= len(string) or not string[sp].isdigit():
762→ if not stack:
763→ return False
764→ pc, sp, captures, registers = stack.pop()
765→ continue
766→ sp += 1
767→ pc += 1
768→
769→ elif opcode == Op.WORD:
770→ if sp >= len(string):
771→ if not stack:
772→ return False
773→ pc, sp, captures, registers = stack.pop()
774→ continue
775→ ch = string[sp]
776→ if ch.isalnum() or ch == '_':
777→ sp += 1
778→ pc += 1
779→ else:
780→ if not stack:
781→ return False
782→ pc, sp, captures, registers = stack.pop()
783→
784→ elif opcode == Op.SPLIT_FIRST:
785→ alt_pc = instr[1]
786→ stack.append((alt_pc, sp, [c.copy() for c in captures], registers.copy()))
787→ pc += 1
788→
789→ elif opcode == Op.SPLIT_NEXT:
790→ alt_pc = instr[1]
791→ stack.append((pc + 1, sp, [c.copy() for c in captures], registers.copy()))
792→ pc = alt_pc
793→
794→ elif opcode == Op.JUMP:
795→ pc = instr[1]
796→
797→ elif opcode == Op.MATCH:
798→ # Check if we ended exactly at the target position
799→ return sp == end_pos
800→
801→ else:
802→ # Handle other opcodes - advance pc
803→ pc += 1
804→uv run pytest tests/test_regex.py::TestLookbehind -v 2>&1
============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python cachedir: .pytest_cache rootdir: /home/user/mquickjs-python configfile: pyproject.toml collecting ... collected 2 items tests/test_regex.py::TestLookbehind::test_positive_lookbehind XPASS [ 50%] tests/test_regex.py::TestLookbehind::test_negative_lookbehind XPASS [100%] ============================== 2 xpassed in 0.08s ==============================
Excellent! Both lookbehind tests pass. Let me remove the xfail markers from those tests:
{
"file_path": "/home/user/mquickjs-python/tests/test_regex.py",
"limit": 25,
"offset": 433
} 433→
434→
435→class TestLookbehind:
436→ """Test lookbehind assertions."""
437→
438→ @pytest.mark.xfail(reason="Lookbehind not yet implemented")
439→ def test_positive_lookbehind(self):
440→ """Positive lookbehind (?<=...)."""
441→ re = RegExp(r"(?<=foo)bar")
442→ assert re.test("foobar") is True
443→ assert re.test("bazbar") is False
444→
445→ @pytest.mark.xfail(reason="Lookbehind not yet implemented")
446→ def test_negative_lookbehind(self):
447→ """Negative lookbehind (?<!...)."""
448→ re = RegExp(r"(?<!foo)bar")
449→ assert re.test("bazbar") is True
450→ assert re.test("foobar") is False
451→
452→
453→class TestExec:
454→ """Test exec() method and match results."""
455→
456→ def test_exec_returns_array(self):
457→ """exec returns array-like result."""
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
class TestLookbehind:
"""Test lookbehind assertions."""
@pytest.mark.xfail(reason="Lookbehind not yet implemented")
def test_positive_lookbehind(self):
"""Positive lookbehind (?<=...)."""
re = RegExp(r"(?<=foo)bar")
assert re.test("foobar") is True
assert re.test("bazbar") is False
@pytest.mark.xfail(reason="Lookbehind not yet implemented")
def test_negative_lookbehind(self):
"""Negative lookbehind (?<!...)."""
re = RegExp(r"(?<!foo)bar")
assert re.test("bazbar") is True
assert re.test("foobar") is Falseclass TestLookbehind:
"""Test lookbehind assertions."""
def test_positive_lookbehind(self):
"""Positive lookbehind (?<=...)."""
re = RegExp(r"(?<=foo)bar")
assert re.test("foobar") is True
assert re.test("bazbar") is False
def test_negative_lookbehind(self):
"""Negative lookbehind (?<!...)."""
re = RegExp(r"(?<!foo)bar")
assert re.test("bazbar") is True
assert re.test("foobar") is FalseThe file /home/user/mquickjs-python/tests/test_regex.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
431→ assert re.test("foobaz") is True
432→ assert re.test("foobar") is False
433→
434→
435→class TestLookbehind:
436→ """Test lookbehind assertions."""
437→
438→ def test_positive_lookbehind(self):
439→ """Positive lookbehind (?<=...)."""
440→ re = RegExp(r"(?<=foo)bar")
441→ assert re.test("foobar") is True
442→ assert re.test("bazbar") is False
443→
444→ def test_negative_lookbehind(self):
445→ """Negative lookbehind (?<!...)."""
446→ re = RegExp(r"(?<!foo)bar")
447→ assert re.test("bazbar") is True
448→ assert re.test("foobar") is False
449→
450→
451→class TestExec:
452→ """Test exec() method and match results."""configfile: pyproject.toml collected 388 items tests/test_arrow_functions.py ............. [ 3%] tests/test_basic.py . [ 3%] tests/test_compatibility.py ............................................ [ 14%] . [ 15%] tests/test_function_methods.py ........... [ 18%] tests/test_js_basic.py .....................xxxxx [ 24%] tests/test_jscontext_regexp.py .................. [ 29%] tests/test_lexer.py .................................................... [ 42%] .. [ 43%] tests/test_parser.py ................................................... [ 56%] ........ [ 58%] tests/test_regex.py .................................................... [ 71%] .................................... [ 81%] tests/test_string_regex.py ................... [ 86%] tests/test_vm.py ...................................................... [100%] ======================== 383 passed, 5 xfailed in 4.79s ========================
383 passed, 5 xfailed. The lookbehind tests now pass and aren't xfailed anymore. Let me commit this:
git add -A && git commit -m "$(cat <<'EOF' Implement regex lookbehind assertions - Add _execute_lookbehind and _try_lookbehind_at methods to regex VM - Update LOOKBEHIND and LOOKBEHIND_NEG opcode handlers - Lookbehind tries all possible start positions backwards from current position - Remove xfail markers from lookbehind tests EOF )"
2 files changed, 149 insertions(+), 11 deletions(-)
To http://127.0.0.1:50794/git/simonw/mquickjs-python 6cf3a86..2c07659 claude/python-mquickjs-port-uPKcc -> claude/python-mquickjs-port-uPKcc branch 'claude/python-mquickjs-port-uPKcc' set up to track 'origin/claude/python-mquickjs-port-uPKcc'.
Todos have been modified successfully. Ensure that you continue to use the todo list to track your progress. Please proceed with the current tasks if applicable
All tasks are complete. Let me summarize what was accomplished:
void operator in compiler.pyTest results: 383 passed, 5 xfailed (down from 7-8 xfailed)
All tasks complete! Here's a summary of what was implemented:
Completed:
1. Void operator - void 0 returns undefined
2. For...of loops - for (x of arr) iterates values
3. Getter/setter syntax - get x() {} and set x(v) {} in object literals
4. Reserved words as properties - {if: 1} and obj.if now work
5. Try-finally-break - Finally blocks execute before break/continue/return
6. Regex lookbehind - (?<=foo)bar and (?<!foo)bar assertions
Test results: 383 passed, 5 xfailed
The 5 remaining xfailed tests are the original mquickjs tests that still need more features:
- mandelbrot.js
- microbench.js
- test_builtin.js
- test_language.js
- test_rect.js
The user wants me to analyze the remaining xfail tests (mandelbrot.js, microbench.js, test_builtin.js, test_language.js, test_rect.js) and build a todo list of features they need to pass.
Let me read each file to understand what features are missing.
1→function throw_error(msg) {
2→ throw Error(msg);
3→}
4→
5→function assert(actual, expected, message) {
6→ function get_full_type(o) {
7→ var type = typeof(o);
8→ if (type === 'object') {
9→ if (o === null)
10→ return 'null';
11→ if (o.constructor && o.constructor.name)
12→ return o.constructor.name;
13→ }
14→ return type;
15→ }
16→
17→ if (arguments.length == 1)
18→ expected = true;
19→
20→ if (typeof actual === typeof expected) {
21→ if (actual === expected) {
22→ if (actual !== 0 || (1 / actual) === (1 / expected))
23→ return;
24→ }
25→ if (typeof actual === 'number') {
26→ if (isNaN(actual) && isNaN(expected))
27→ return true;
28→ }
29→ if (typeof actual === 'object') {
30→ if (actual !== null && expected !== null
31→ && actual.constructor === expected.constructor
32→ && actual.toString() === expected.toString())
33→ return;
34→ }
35→ }
36→ // Should output the source file and line number and extract
37→ // the expression from the assert call
38→ throw_error("assertion failed: got " +
39→ get_full_type(actual) + ":|" + actual + "|, expected " +
40→ get_full_type(expected) + ":|" + expected + "|" +
41→ (message ? " (" + message + ")" : ""));
42→}
43→
44→function assert_throws(expected_error, func)
45→{
46→ var err = false;
47→ try {
48→ func();
49→ } catch(e) {
50→ err = true;
51→ if (!(e instanceof expected_error)) {
52→ // Should output the source file and line number and extract
53→ // the expression from the assert_throws() call
54→ throw_error("unexpected exception type");
55→ return;
56→ }
57→ }
58→ if (!err) {
59→ // Should output the source file and line number and extract
60→ // the expression from the assert_throws() call
61→ throw_error("expected exception");
62→ }
63→}
64→
65→function test_op1()
66→{
67→ var r, a;
68→ r = 1 + 2;
69→ assert(r, 3);
70→
71→ r = 1 - 2;
72→ assert(r, -1);
73→
74→ r = -1;
75→ assert(r, -1, "-1 === -1");
76→
77→ r = +2;
78→ assert(r, 2, "+2 === 2");
79→
80→ r = 2 * 3;
81→ assert(r, 6, "2 * 3 === 6");
82→
83→ r = 4 / 2;
84→ assert(r, 2, "4 / 2 === 2");
85→
86→ r = 4 % 3;
87→ assert(r, 1, "4 % 3 === 3");
88→
89→ r = 4 << 2;
90→ assert(r, 16, "4 << 2 === 16");
91→
92→ r = 1 << 0;
93→ assert(r, 1, "1 << 0 === 1");
94→
95→ r = 1 << 29;
96→ assert(r, 536870912, "1 << 29 === 536870912");
97→
98→ r = 1 << 30;
99→ assert(r, 1073741824, "1 << 30 === 1073741824");
100→
101→ r = 1 << 31;
102→ assert(r, -2147483648, "1 << 31 === -2147483648");
103→
104→ r = 1 << 32;
105→ assert(r, 1, "1 << 32 === 1");
106→
107→ r = (1 << 31) < 0;
108→ assert(r, true, "(1 << 31) < 0 === true");
109→
110→ r = -4 >> 1;
111→ assert(r, -2, "-4 >> 1 === -2");
112→
113→ r = -4 >>> 1;
114→ assert(r, 0x7ffffffe, "-4 >>> 1 === 0x7ffffffe");
115→
116→ r = -1 >>> 0;
117→ assert(r, 0xffffffff);
118→
119→ r = 1 & 1;
120→ assert(r, 1, "1 & 1 === 1");
121→
122→ r = 0 | 1;
123→ assert(r, 1, "0 | 1 === 1");
124→
125→ r = 1 ^ 1;
126→ assert(r, 0, "1 ^ 1 === 0");
127→
128→ r = ~1;
129→ assert(r, -2, "~1 === -2");
130→
131→ r = !1;
132→ assert(r, false, "!1 === false");
133→
134→ assert((1 < 2), true, "(1 < 2) === true");
135→
136→ assert((2 > 1), true, "(2 > 1) === true");
137→
138→ assert(('b' > 'a'), true, "('b' > 'a') === true");
139→
140→ assert(2 ** 8, 256, "2 ** 8 === 256");
141→
142→ /* minus zero */
143→ assert(1/(-0.0), -Infinity);
144→ a = 0;
145→ assert(1/(-a), -Infinity);
146→ assert(1/(0 * -6), -Infinity);
147→
148→ /* 31 bit overflow */
149→ a = 0x3fffffff;
150→ assert(a + 1, 0x40000000);
151→ a = -0x40000000;
152→ assert(-a, 0x40000000);
153→}
154→
155→function test_cvt()
156→{
157→ assert((NaN | 0), 0);
158→ assert((Infinity | 0), 0);
159→ assert(((-Infinity) | 0), 0);
160→ assert(("12345" | 0), 12345);
161→ assert(("0x12345" | 0), 0x12345);
162→ assert(((4294967296 * 3 - 4) | 0), -4);
163→
164→ assert(("12345" >>> 0), 12345);
165→ assert(("0x12345" >>> 0), 0x12345);
166→ assert((NaN >>> 0), 0);
167→ assert((Infinity >>> 0), 0);
168→ assert(((-Infinity) >>> 0), 0);
169→ assert(((4294967296 * 3 - 4) >>> 0), (4294967296 - 4));
170→}
171→
172→function test_eq()
173→{
174→ assert(null == undefined);
175→ assert(undefined == null);
176→ assert(true == 1);
177→ assert(0 == false);
178→ assert("" == 0);
179→ assert("123" == 123);
180→ assert("122" != 123);
181→// assert((new Number(1)) == 1);
182→// assert(2 == (new Number(2)));
183→// assert((new String("abc")) == "abc");
184→// assert({} != "abc");
185→}
186→
187→function test_inc_dec()
188→{
189→ var a, r;
190→
191→ a = 1;
192→ r = a++;
193→ assert(r === 1 && a === 2);
194→
195→ a = 1;
196→ r = ++a;
197→ assert(r === 2 && a === 2);
198→
199→ a = 1;
200→ r = a--;
201→ assert(r === 1 && a === 0);
202→
203→ a = 1;
204→ r = --a;
205→ assert(r === 0 && a === 0);
206→
207→ a = {x:true};
208→ a.x++;
209→ assert(a.x, 2, "++");
210→
211→ a = {x:true};
212→ a.x--;
213→ assert(a.x, 0, "--");
214→
215→ a = [true];
216→ a[0]++;
217→ assert(a[0], 2, "++");
218→
219→ a = {x:true};
220→ r = a.x++;
221→ assert(r === 1 && a.x === 2);
222→
223→ a = {x:true};
224→ r = a.x--;
225→ assert(r === 1 && a.x === 0);
226→
227→ a = [true];
228→ r = a[0]++;
229→ assert(r === 1 && a[0] === 2);
230→
231→ a = [true];
232→ r = a[0]--;
233→ assert(r === 1 && a[0] === 0);
234→}
235→
236→function F(x)
237→{
238→ this.x = x;
239→}
240→
241→function test_op2()
242→{
243→ var a, b;
244→ a = new Object;
245→ a.x = 1;
246→ assert(a.x, 1, "new");
247→ b = new F(2);
248→ assert(b.x, 2, "new");
249→ assert((b instanceof F), true, "instanceof F");
250→
251→ a = {x : 2};
252→ assert(("x" in a), true, "in");
253→ assert(("y" in a), false, "in");
254→
255→ a = {};
256→ assert((a instanceof Object), true, "instanceof Object");
257→ assert((a instanceof String), false, "instanceof String");
258→
259→ assert((typeof 1), "number", "typeof");
260→ assert((typeof Object), "function", "typeof");
261→ assert((typeof null), "object", "typeof");
262→ assert((typeof unknown_var), "undefined", "typeof");
263→
264→ a = {x: 1, y: 1};
265→ assert((delete a.x), true, "delete");
266→ assert(("x" in a), false, "delete in");
267→
268→ a = {x: 1, if: 2};
269→ assert(a.if, 2);
270→
271→ a = {x: 1, y: 2, __proto__: { z: 3 }};
272→ assert(a.x, 1);
273→ assert(a.y, 2);
274→ assert(Object.getPrototypeOf(a).z, 3);
275→
276→ /* getter/setter/method */
277→ b = 2;
278→ a = {get x() { return b; }, set x(v) { b = v; }, f(v) { return v + 1 },
279→ set: 10, get: 11 };
280→ assert(a.x, 2);
281→ a.x = 3;
282→ assert(a.x, 3);
283→ assert(a.f(3), 4);
284→ assert(a.set, 10);
285→ assert(a.get, 11);
286→
287→ a = { set() { return 1; }, get() { return 2; }}
288→ assert(a.set(), 1);
289→ assert(a.get(), 2);
290→}
291→
292→function test_prototype()
293→{
294→ function f() { }
295→ assert(f.prototype.constructor, f, "prototype");
296→}
297→
298→function test_arguments()
299→{
300→ function f2() {
301→ assert(arguments.length, 2, "arguments");
302→ assert(arguments[0], 1, "arguments");
303→ assert(arguments[1], 3, "arguments");
304→ }
305→ f2(1, 3);
306→}
307→
308→function test_to_primitive()
309→{
310→ var obj;
311→ obj = { x : "abc", y: 1234 };
312→ obj.toString = function () { return this.x; };
313→ obj.valueOf = function () { return this.y; };
314→ assert(obj + "", "1234");
315→ assert(obj * 1, 1234);
316→}
317→
318→function test_labels()
319→{
320→ do x: { break x; } while(0);
321→ if (1)
322→ x: { break x; }
323→ else
324→ x: { break x; }
325→ while (0) x: { break x; };
326→}
327→
328→function test_labels2()
329→{
330→ while (1) label: break
331→ var i = 0
332→ while (i < 3) label: {
333→ if (i > 0)
334→ break
335→ i++
336→ }
337→ assert(i == 1)
338→ for (;;) label: break
339→ for (i = 0; i < 3; i++) label: {
340→ if (i > 0)
341→ break
342→ }
343→ assert(i == 1)
344→}
345→
346→test_op1();
347→test_cvt();
348→test_eq();
349→test_inc_dec();
350→test_op2();
351→test_prototype();
352→test_arguments();
353→test_to_primitive();
354→test_labels();
355→test_labels2();
356→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
1→"use strict";
2→
3→function throw_error(msg) {
4→ throw Error(msg);
5→}
6→
7→function assert(actual, expected, message) {
8→ function get_full_type(o) {
9→ var type = typeof(o);
10→ if (type === 'object') {
11→ if (o === null)
12→ return 'null';
13→ if (o.constructor && o.constructor.name)
14→ return o.constructor.name;
15→ }
16→ return type;
17→ }
18→
19→ if (arguments.length == 1)
20→ expected = true;
21→
22→ if (typeof actual === typeof expected) {
23→ if (actual === expected) {
24→ if (actual !== 0 || (1 / actual) === (1 / expected))
25→ return;
26→ }
27→ if (typeof actual === 'number') {
28→ if (isNaN(actual) && isNaN(expected))
29→ return true;
30→ }
31→ if (typeof actual === 'object') {
32→ if (actual !== null && expected !== null
33→ && actual.constructor === expected.constructor
34→ && actual.toString() === expected.toString())
35→ return;
36→ }
37→ }
38→ // Should output the source file and line number and extract
39→ // the expression from the assert call
40→ throw_error("assertion failed: got " +
41→ get_full_type(actual) + ":|" + actual + "|, expected " +
42→ get_full_type(expected) + ":|" + expected + "|" +
43→ (message ? " (" + message + ")" : ""));
44→}
45→
46→function assert_throws(expected_error, func)
47→{
48→ var err = false;
49→ try {
50→ func();
51→ } catch(e) {
52→ err = true;
53→ if (!(e instanceof expected_error)) {
54→ // Should output the source file and line number and extract
55→ // the expression from the assert_throws() call
56→ throw_error("unexpected exception type");
57→ return;
58→ }
59→ }
60→ if (!err) {
61→ // Should output the source file and line number and extract
62→ // the expression from the assert_throws() call
63→ throw_error("expected exception");
64→ }
65→}
66→
67→function my_func(a, b)
68→{
69→ return a + b;
70→}
71→
72→function test_function()
73→{
74→ function f(a, b) {
75→ var i, tab = [];
76→ tab.push(this);
77→ for(i = 0; i < arguments.length; i++)
78→ tab.push(arguments[i]);
79→ return tab;
80→ }
81→ function constructor1(a) {
82→ this.x = a;
83→ }
84→
85→ var r, g;
86→
87→ r = my_func.call(null, 1, 2);
88→ assert(r, 3, "call");
89→
90→ r = my_func.apply(null, ["abc", 2]);
91→ assert(r, "abc2", "apply");
92→
93→ r = new Function("a", "b", "return a + b;");
94→ assert(r(2,3), 5, "function");
95→
96→ g = f.bind(1, 2);
97→// assert(g.length, 1);
98→// assert(g.name, "bound f");
99→ assert(g(3).toString(), "1,2,3");
100→
101→ if (0) {
102→ g = constructor1.bind(null, 1);
103→ r = new g();
104→ assert(r.x, 1);
105→ }
106→}
107→
108→function test()
109→{
110→ var r, a, b, c, err;
111→
112→ r = Error("hello");
113→ assert(r.message, "hello", "Error");
114→
115→ a = new Object();
116→ a.x = 1;
117→ assert(a.x, 1, "Object");
118→
119→ assert(Object.prototype.constructor, Object, "constructor");
120→ assert(Object.getPrototypeOf(a), Object.prototype, "getPrototypeOf");
121→ Object.defineProperty(a, "y", { value: 3, writable: true, configurable: true, enumerable: true });
122→ assert(a.y, 3, "defineProperty");
123→
124→ Object.defineProperty(a, "z", { get: function () { return 4; }, set: function(val) { this.z_val = val; }, configurable: true, enumerable: true });
125→ assert(a.z, 4, "get");
126→ a.z = 5;
127→ assert(a.z_val, 5, "set");
128→/*
129→ a = { get z() { return 4; }, set z(val) { this.z_val = val; } };
130→ assert(a.z, 4, "get");
131→ a.z = 5;
132→ assert(a.z_val, 5, "set");
133→*/
134→ a = {};
135→ b = Object.create(a);
136→ assert(Object.getPrototypeOf(b), a, "create");
137→ c = {u:2};
138→ Object.setPrototypeOf(a, c);
139→ assert(Object.getPrototypeOf(a), c, "setPrototypeOf");
140→
141→ a={};
142→ assert(a.toString(), "[object Object]", "toString");
143→ assert(Object.prototype.toString.call(1), "[object Number]", "toString");
144→/*
145→ a={x:1};
146→ assert(Object.isExtensible(a), true, "extensible");
147→ Object.preventExtensions(a);
148→
149→ err = false;
150→ try {
151→ a.y = 2;
152→ } catch(e) {
153→ err = true;
154→ }
155→ assert(Object.isExtensible(a), false, "extensible");
156→ assert(typeof a.y, "undefined", "extensible");
157→ assert(err);
158→*/
159→
160→ a = {x: 1};
161→ assert(a.hasOwnProperty("x"), true);
162→ assert(a.hasOwnProperty("y"), false);
163→ a = [1, 2];
164→ assert(a.hasOwnProperty(1), true);
165→ assert(a.hasOwnProperty(2), false);
166→}
167→
168→function test_enum()
169→{
170→ var a, tab;
171→ a = {x:1, y:1, z:3};
172→ tab = Object.keys(a);
173→ assert(tab.toString(), "x,y,z", "keys");
174→}
175→
176→function test_array()
177→{
178→ var a, err, i, log;
179→
180→ a = [1, 2, 3];
181→ assert(a.length, 3, "array");
182→ assert(a[2], 3, "array1");
183→
184→ a = new Array(10);
185→ assert(a.length, 10, "array2");
186→
187→ a = new Array(1, 2);
188→ assert(a[0] === 1 && a[1] === 2);
189→
190→ a = [1, 2, 3];
191→ a.length = 2;
192→ assert(a[0] === 1 && a[1] === 2 && a.length === 2);
193→
194→ a = [];
195→ a[0] = 10;
196→ a[1] = 3;
197→ assert(a.length, 2);
198→
199→/*
200→ a = [];
201→ a[1] = 10;
202→ a[4] = 3;
203→ assert(a.length, 5);
204→*/
205→
206→ a = [1,2];
207→ a.length = 5;
208→ a[4] = 1;
209→ a.length = 4;
210→ assert(a[4] !== 1);
211→
212→ a = [1,2,3];
213→ assert(a.join("-"), "1-2-3");
214→
215→ a = [1,2];
216→ assert(a.push(3, 4), 4);
217→ assert(a.toString(), "1,2,3,4");
218→
219→ a = [1,2,3];
220→ assert(a.pop(), 3);
221→ assert(a.toString(), "1,2");
222→
223→ /*
224→ a=[1,2,3,4,5];
225→ Object.defineProperty(a, "3", { configurable: false });
226→ err = false;
227→ try {
228→ a.length = 2;
229→ } catch(e) {
230→ err = true;
231→ }
232→ assert(err && a.toString() === "1,2,3,4");
233→ */
234→ assert(Array.isArray([]), true);
235→ assert(Array.isArray({}), false);
236→
237→ a = [1, 2, 3];
238→ assert(a.reverse().toString(), "3,2,1");
239→
240→ a = [1, 2, 3];
241→ a = a.concat(4, [5, 6], 7);
242→ assert(a.toString(), "1,2,3,4,5,6,7");
243→
244→ a = [1, 2, 3];
245→ assert(a.shift(), 1);
246→ assert(a.toString(), "2,3");
247→
248→ a = [3,4];
249→ assert(a.unshift(1,2), 4);
250→ assert(a.toString(), "1,2,3,4");
251→
252→ a = [10, 11, 10, 11]
253→ assert(a.indexOf(11), 1);
254→ assert(a.indexOf(9), -1);
255→ assert(a.indexOf(11, 2), 3);
256→ assert(a.lastIndexOf(11), 3);
257→ assert(a.lastIndexOf(11, 2), 1);
258→
259→ assert([1, 2, 3, 4].slice(1, 3).toString(), "2,3");
260→ assert([1, 2, 3, 4].slice(1).toString(), "2,3,4");
261→
262→ log="";
263→ assert([1, 2, 3, 4].every(function(val, k) { log += val; assert(k, (val - 1)); return val != 5 }), true);
264→ assert(log, "1234");
265→
266→ log = "";
267→ assert([1, 2, 3, 4].some(function(val, k) { log += val; assert(k, (val - 1)); return val == 5 }), false);
268→ assert(log, "1234");
269→
270→ log = "";
271→ assert([1, 2, 3, 4].forEach(function(val, k) { log += val; assert(k, (val - 1)); }), void 0);
272→ assert(log, "1234");
273→
274→ log = "";
275→ a = [1, 2, 3, 4].map(function(val, k) { assert(k, (val - 1)); return val + 1; });
276→ assert(a.toString(), "2,3,4,5");
277→
278→ log = "";
279→ a = [1, 2, 3, 4].filter(function(val, k) { assert(k, (val - 1)); return val == 2 || val == 3; });
280→ assert(a.toString(), "2,3");
281→
282→ assert(["1", 2, 3, 4].reduce(function(acc, val, k) { assert(k, (val - 1)); return acc + val; }), "1234");
283→ assert([1, 2, 3, 4].reduce(function(acc, val, k) { assert(k, (val - 1)); return acc + val; }, "0"), "01234");
284→
285→ assert([1, 2, 3, "4"].reduceRight(function(acc, val, k) { assert(k, (val - 1)); return acc + val; }), "4321");
286→ assert([1, 2, 3, 4].reduceRight(function(acc, val, k) { assert(k, (val - 1)); return acc + val; }, "5"), "54321");
287→
288→ a = [1, 2, 3, 4];
289→ assert(a.splice(1, 2, 10, 11, 12).toString(), "2,3");
290→ assert(a.toString(), "1,10,11,12,4");
291→
292→ a = [1, 2, 3, 4];
293→ assert(a.splice(1, 2, 10).toString(), "2,3");
294→ assert(a.toString(), "1,10,4");
295→
296→ a = [5, 4, 3, 2, 1];
297→ a.sort();
298→ assert(a[0], 1);
299→ assert(a.toString(), "1,2,3,4,5");
300→
301→ a = [1, 2, 3, 4, 5];
302→ a.sort(function(a, b) { return (a < b) - (a > b) } );
303→ assert(a.toString(), "5,4,3,2,1");
304→
305→ /* verify that the sort is stable and that 'undefined' is correctly handled */
306→ a = [ "b0", "z0", undefined, "b1", "a0", undefined, "z1", "a1", "a2"];
307→ a.sort(function(a, b) { return (a[0] > b[0]) - (a[0] < b[0]) } );
308→ assert(a.toString(), "a0,a1,a2,b0,b1,z0,z1,,");
309→}
310→
311→/* non standard array behaviors */
312→function test_array_ext()
313→{
314→ var a;
315→ a = [1, 2, 3];
316→ assert_throws(TypeError, function () { a[1.2] = 1; } );
317→ assert_throws(TypeError, function () { a[NaN] = 1; } );
318→ assert_throws(TypeError, function () { a.NaN = 1; } );
319→ assert_throws(TypeError, function () { a[Infinity] = 1; } );
320→ assert_throws(TypeError, function () { a.Infinity = 1; } );
321→ assert_throws(TypeError, function () { a[-Infinity] = 1; } );
322→ assert_throws(TypeError, function () { a["1.2"] = 1; } );
323→ assert_throws(TypeError, function () { a["NaN"] = 1; } );
324→ assert_throws(TypeError, function () { a["Infinity"] = 1; } );
325→ assert_throws(TypeError, function () { a["-Infinity"] = 1; } );
326→}
327→
328→function test_string()
329→{
330→ var a;
331→ a = String("abc");
332→ assert(a.length, 3, "string");
333→ assert(a[1], "b", "string");
334→ assert(a.charCodeAt(1), 0x62, "string");
335→ assert(String.fromCharCode(65), "A", "string");
336→ assert(String.fromCharCode(65, 66, 67), "ABC", "string");
337→ assert(a.charAt(1), "b");
338→ assert(a.charAt(-1), "");
339→ assert(a.charAt(3), "");
340→
341→ a = "abcd";
342→ assert(a.substring(1, 3), "bc", "substring");
343→ a = String.fromCharCode(0x20ac);
344→ assert(a.charCodeAt(0), 0x20ac, "unicode");
345→ assert(a, "€", "unicode");
346→ assert(a, "\u20ac", "unicode");
347→ assert(a, "\u{20ac}", "unicode");
348→ assert("a", "\x61", "unicode");
349→
350→ a = "\u{10ffff}";
351→ assert(a.length, 2, "unicode");
352→ assert(a, "\u{dbff}\u{dfff}", "unicode");
353→ assert(a.codePointAt(0), 0x10ffff);
354→ assert(a.codePointAt(1), 0xdfff);
355→ assert(String.fromCodePoint(0x10ffff), a);
356→
357→ assert("a".concat("b", "c", 123), "abc123");
358→
359→ assert("abcabc".indexOf("cab"), 2);
360→ assert("abcabc".indexOf("cab2"), -1);
361→ assert("abc".indexOf("c"), 2);
362→ assert("abcabc".lastIndexOf("ab"), 3);
363→
364→ a = "a,b,c".split(",");
365→ assert(a.length === 3 && a[0] === "a" && a[1] === "b" && a[2] === "c");
366→ a = ",b,c".split(",");
367→ assert(a.length === 3 && a[0] === "" && a[1] === "b" && a[2] === "c");
368→ a = "a,b,".split(",");
369→ assert(a.length === 3 && a[0] === "a" && a[1] === "b" && a[2] === "");
370→
371→// assert((1,eval)('"\0"'), "\0");
372→ assert("123AbCd€".toLowerCase(), "123abcd€");
373→ assert("123AbCd€".toUpperCase(), "123ABCD€");
374→ assert(" ab€cd ".trim(), "ab€cd");
375→ assert(" ab€cd ".trimStart(), "ab€cd ");
376→ assert(" ab€cd ".trimEnd(), " ab€cd");
377→ assert("abcabc".replace("b", "a$$b$&"), "aa$bbcabc");
378→ assert("abcabc".replaceAll("b", "a$$b$&"),"aa$bbcaa$bbc");
379→}
380→
381→/* specific tests for internal UTF-8 storage */
382→function test_string2()
383→{
384→ var str = "hé€\u{101234}o";
385→ assert(str, "h\xe9\u20ac\udbc4\u{de34}o", "parse");
386→ assert(str.length, 6, "length");
387→ assert(str.slice(1, 2), "é", "slice");
388→ assert(str.slice(1, 3), "é€", "slice");
389→ assert(str.slice(2, 5), "€\u{101234}", "slice");
390→ assert(str.slice(2, 4), "€\u{dbc4}", "slice");
391→ assert(str.slice(4, 6), "\u{de34}o", "slice");
392→ assert("hé€" + "\u{101234}o", str, "concat 1");
393→ assert("h\xe9\u20ac\udbc4" + "\u{de34}o", str, "concat 2");
394→
395→ var ch = "\udbc4\u{de34}";
396→ assert(ch.slice(0, 2), "\udbc4\u{de34}", "slice 1");
397→ assert(ch.slice(0, 1), "\udbc4", "slice 1");
398→ assert(ch.slice(1, 2), "\u{de34}", "slice 1");
399→
400→ assert("\udbc4" + "\u{de34}", "\u{101234}", "concat 3");
401→ assert("\udbc4" + "o\u{de34}", "\udbc4o\u{de34}", "concat 4");
402→
403→ assert(str[0], "h", "char 1");
404→ assert(str[1], "é", "char 2");
405→ assert(str[3], "\u{dbc4}", "char 3");
406→ assert(str[4], "\u{de34}", "char 4");
407→ assert(str.charCodeAt(3), 0xdbc4, "char 4");
408→ assert("€"[0], "€", "char 5");
409→ assert("\u{101234}"[0], "\u{dbc4}", "char 6");
410→ assert("\u{101234}"[1], "\u{de34}", "char 6");
411→
412→ assert("\udbc4" <= "\udbc4", true);
413→ assert("\udbc3" < "\u{101234}", true);
414→ assert("\udbc4" < "\u{101234}", true);
415→ assert("\udbc5" > "\u{101234}", true);
416→
417→ assert("\u{101234}" > "\udbc3", true);
418→ assert("\u{101234}" > "\udbc4", true);
419→ assert("\u{101234}" < "\udbc5", true);
420→
421→ assert("\u{101233}" < "\u{101234}", true);
422→}
423→
424→function test_math()
425→{
426→ var a;
427→ a = 1.4;
428→ assert(Math.floor(a), 1);
429→ assert(Math.ceil(a), 2);
430→ assert(Math.imul(0x12345678, 123), -1088058456);
431→ assert(Math.fround(0.1), 0.10000000149011612);
432→}
433→
434→function test_number()
435→{
436→ assert(+" 123 ", 123);
437→ assert(+"0b111", 7);
438→ assert(+"0o123", 83);
439→
440→ assert(parseInt("123"), 123);
441→ assert(parseInt(" 123r"), 123);
442→ assert(parseInt("0x123"), 0x123);
443→ assert(parseInt("0o123"), 0);
444→ assert(parseFloat("0x1234"), 0);
445→ assert(parseFloat("Infinity"), Infinity);
446→ assert(parseFloat("-Infinity"), -Infinity);
447→ assert(parseFloat("123.2"), 123.2);
448→ assert(parseFloat("123.2e3"), 123200);
449→
450→ assert((25).toExponential(), "2.5e+1");
451→ assert((25).toExponential(0), "3e+1");
452→ assert((-25).toExponential(0), "-3e+1");
453→ assert((2.5).toPrecision(1), "3");
454→ assert((-2.5).toPrecision(1), "-3");
455→ assert((25).toPrecision(1), "3e+1");
456→ assert((1.125).toFixed(2), "1.13");
457→ assert((-1.125).toFixed(2), "-1.13");
458→ assert((-1e-10).toFixed(0), "-0");
459→}
460→
461→function test_global_eval()
462→{
463→ var r, g_eval = (1,eval);
464→
465→ r = g_eval("1+1;");
466→ assert(r, 2, "eval");
467→
468→ /* z is created as a global variable */
469→ r = g_eval("var z=2; z;");
470→ assert(r, 2, "eval");
471→ assert(z, 2);
472→
473→ assert(g_eval("if (1) 2; else 3;"), 2);
474→ assert(g_eval("if (0) 2; else 3;"), 3);
475→
476→ z = 2;
477→ assert(g_eval("z"), 2);
478→
479→ g_eval("z = 3");
480→ assert(z, 3);
481→}
482→
483→function test_typed_array()
484→{
485→ var buffer, a, i;
486→
487→ a = new Uint8Array(4);
488→ assert(a.length, 4);
489→ for(i = 0; i < a.length; i++)
490→ a[i] = i;
491→ assert(a.toString(), "0,1,2,3");
492→ a[0] = -1;
493→ assert(a[0], 255);
494→
495→ a = new Int8Array(3);
496→ a[0] = 255;
497→ assert(a[0], -1);
498→
499→ a = new Int32Array(3);
500→ a[0] = Math.pow(2, 32) - 1;
501→ assert(a[0], -1);
502→ assert(a.BYTES_PER_ELEMENT, 4);
503→
504→ a = new Uint8ClampedArray(4);
505→ a[0] = -100;
506→ a[1] = 1.5;
507→ a[2] = 0.5;
508→ a[3] = 1233.5;
509→ assert(a.toString(), "0,2,0,255");
510→
511→ buffer = new ArrayBuffer(16);
512→ assert(buffer.byteLength, 16);
513→ a = new Uint32Array(buffer, 12, 1);
514→ assert(a.length, 1);
515→ a[0] = -1;
516→
517→ a = new Uint16Array(buffer, 2);
518→ a[0] = -1;
519→
520→ a = new Float32Array(buffer, 8, 1);
521→ a[0] = 1;
522→
523→ a = new Uint8Array(buffer);
524→
525→ assert(a.toString(), "0,0,255,255,0,0,0,0,0,0,128,63,255,255,255,255");
526→
527→ assert(a.buffer, buffer);
528→
529→ a = new Uint8Array([1, 2, 3, 4]);
530→ assert(a.toString(), "1,2,3,4");
531→ if (0) {
532→ a.set([10, 11], 2);
533→ assert(a.toString(), "1,2,10,11");
534→ }
535→
536→ a = new Uint8Array([1, 2, 3, 4]);
537→ a = a.subarray(1, 3);
538→ assert(a.toString(), "2,3");
539→}
540→
541→function repeat(a, n)
542→{
543→ var i, r;
544→ r = "";
545→ while (n != 0) {
546→ if (n & 1)
547→ r += a;
548→ a += a;
549→ n >>>= 1;
550→ }
551→ return r;
552→}
553→
554→/* return [s, line_num, col_num] where line_num and col_num are the
555→ position of the '@' character in 'str'. 's' is str without the '@'
556→ character */
557→function get_string_pos(str)
558→{
559→ var p, line_num, col_num, s, q, r;
560→ p = str.indexOf('@');
561→ assert(p >= 0, true);
562→ q = 0;
563→ line_num = 1;
564→ for(;;) {
565→ r = str.indexOf('\n', q);
566→ if (r < 0 || r >= p)
567→ break;
568→ q = r + 1;
569→ line_num++;
570→ }
571→ col_num = p - q + 1;
572→ s = str.slice(0, p) + str.slice(p + 1);
573→ return [s, line_num, col_num];
574→}
575→
576→function check_error_pos(e, expected_error, line_num, col_num, level)
577→{
578→ var expected_pos, tab, line;
579→ level |= 0;
580→ expected_pos = ":" + line_num + ":" + col_num;
581→ tab = e.stack.split("\n");
582→ line = tab[level];
583→ if (line.slice(-1) == ')')
584→ line = line.slice(0, -1);
585→ if (line.indexOf(expected_pos) < 0) {
586→ throw_error("unexpected line or column number. error=|" + e.message +
587→ "| got |" + line + "|, expected |" + expected_pos + "|");
588→ }
589→}
590→
591→function assert_json_error(str, line_num, col_num)
592→{
593→ var err = false;
594→ var expected_pos, tab;
595→
596→ tab = get_string_pos(str);
597→
598→ try {
599→ JSON.parse(tab[0]);
600→ } catch(e) {
601→ err = true;
602→ if (!(e instanceof SyntaxError)) {
603→ throw_error("unexpected exception type");
604→ return;
605→ }
606→ /* XXX: the way quickjs returns JSON errors is not similar to Node or spiderMonkey */
607→ check_error_pos(e, SyntaxError, tab[1], tab[2]);
608→ }
609→ if (!err) {
610→ throw_error("expected exception");
611→ }
612→}
613→
614→function test_json()
615→{
616→ var a, s, n;
617→
618→ s = '{"x":1,"y":true,"z":null,"a":[1,2,false],"1234":"str"}';
619→ a = JSON.parse(s);
620→ assert(a.x, 1);
621→ assert(a.y, true);
622→ assert(a.z, null);
623→ assert(a[1234], "str");
624→ assert(JSON.stringify(a), s);
625→
626→ assert(JSON.stringify({x: 1, y: undefined, z:2}), '{"x":1,"z":2}');
627→
628→ /* larger stack */
629→ n = 100;
630→ s = repeat("[", n) + repeat("]", n);
631→ a = JSON.parse(s);
632→ assert(JSON.stringify(a), s);
633→
634→// assert_json_error('\n" \\@x"');
635→// assert_json_error('\n{ "a": @x }"');
636→}
637→
638→function test_large_eval_parse_stack()
639→{
640→ var n = 1000;
641→ var str;
642→
643→ str = repeat("(", n) + "1" + repeat(")", n);
644→ assert((1,eval)(str), 1);
645→
646→ str = repeat("{", n) + "1;" + repeat("}", n);
647→ assert((1,eval)(str), 1);
648→
649→ str = repeat("[", n) + "1" + repeat("]", n) + repeat("[0]", n);
650→ assert((1,eval)(str), 1);
651→}
652→
653→function test_regexp()
654→{
655→ var a, str, n;
656→
657→ str = "abbbbbc";
658→ a = /(b+)c/.exec(str);
659→ assert(a[0], "bbbbbc");
660→ assert(a[1], "bbbbb");
661→ assert(a.index, 1);
662→ assert(a.input, str);
663→ a = /(b+)c/.test(str);
664→ assert(a, true);
665→ assert(/\x61/.exec("a")[0], "a");
666→ assert(/\u0061/.exec("a")[0], "a");
667→ assert(/\ca/.exec("\x01")[0], "\x01");
668→ assert(/\\a/.exec("\\a")[0], "\\a");
669→ assert(/\c0/.exec("\\c0")[0], "\\c0");
670→
671→ a = /(\.(?=com|org)|\/)/.exec("ah.com");
672→ assert(a.index === 2 && a[0] === ".");
673→
674→ a = /(\.(?!com|org)|\/)/.exec("ah.com");
675→ assert(a, null);
676→
677→ a = /(?=(a+))/.exec("baaabac");
678→ assert(a.index === 1 && a[0] === "" && a[1] === "aaa");
679→
680→ a = /(z)((a+)?(b+)?(c))*/.exec("zaacbbbcac");
681→ assert(a, ["zaacbbbcac","z","ac","a", undefined,"c"]);
682→
683→// a = (1,eval)("/\0a/");
684→// assert(a.toString(), "/\0a/");
685→// assert(a.exec("\0a")[0], "\0a");
686→
687→// assert(/{1a}/.toString(), "/{1a}/");
688→// a = /a{1+/.exec("a{11");
689→// assert(a, ["a{11"]);
690→
691→ /* test zero length matches */
692→ a = /(?:(?=(abc)))a/.exec("abc");
693→ assert(a, ["a", "abc"]);
694→ a = /(?:(?=(abc)))?a/.exec("abc");
695→ assert(a, ["a", undefined]);
696→ a = /(?:(?=(abc))){0,2}a/.exec("abc");
697→ assert(a, ["a", undefined]);
698→ a = /(?:|[\w])+([0-9])/.exec("123a23");
699→ assert(a, ["123a23", "3"]);
700→ a = /()*?a/.exec(",");
701→ assert(a, null);
702→
703→ /* test \b escape */
704→ assert(/[\q{a\b}]/.test("a\b"), true);
705→ assert(/[\b]/.test("\b"), true);
706→
707→ /* test case insensitive matching (test262 hardly tests it) */
708→ assert("aAbBcC".replace(/[^b]/gui, "X"), "XXbBXX");
709→ assert("aAbBcC".replace(/[^A-B]/gui, "X"), "aAbBXX");
710→
711→ /* case where lastIndex points to the second element of a
712→ surrogate pair */
713→ a = /(?:)/gu;
714→ a.lastIndex = 1;
715→ a.exec("🐱");
716→ assert(a.lastIndex, 0);
717→
718→ /* test backreferences */
719→ assert(/(abc)\1/.exec("abcabc"), ["abcabc", "abc"]);
720→ assert(/(abc)\1/i.exec("aBcaBC"), ["aBcaBC", "aBc"]);
721→
722→ /* large parse stack */
723→ n = 10000;
724→ a = new RegExp(repeat("(?:", n) + "a+" + repeat(")", n));
725→ assert(a.exec("aa"), ["aa"]);
726→
727→ /* additional functions */
728→
729→ a = "abbbc".match(/b+/);
730→ assert(a, [ "bbb" ]);
731→ assert("abcaaad".match(/a+/g), [ "a", "aaa" ]);
732→
733→ assert("abc".search(/b/), 1);
734→ assert("abc".search(/d/), -1);
735→
736→ assert("abbbbcbbd".replace(/b+/, "€$&"), "a€bbbbcbbd");
737→ assert("abbbbcbbd".replace(/b+/g, "€$&"), "a€bbbbc€bbd");
738→ assert("abbbbccccd".replace(/(b+)(c+)/g, "_$1_$2_"), "a_bbbb_cccc_d");
739→ assert("abbbbcd".replace(/b+/g, "_$`_$&_$'_"), "a_a_bbbb_cd_cd");
740→
741→ assert("abc".split(/b/), ["a", "c"]);
742→ assert("ab".split(/a*/g), ["", "b"]);
743→ assert("ab".split(/a*?/g), ["a", "b"]);
744→ assert("abc".split(/b/), ["a", "c"]);
745→ assert("A<B>bold</B>and<CODE>coded</CODE>".split(/<(\/)?([^<>]+)>/), ["A", undefined, "B", "bold", "/", "B", "and", undefined, "CODE", "coded", "/", "CODE", ""]);
746→}
747→
748→function eval_error(eval_str, expected_error, level)
749→{
750→ var err = false;
751→ var expected_pos, tab;
752→
753→ tab = get_string_pos(eval_str);
754→
755→ try {
756→ (1, eval)(tab[0]);
757→ } catch(e) {
758→ err = true;
759→ if (!(e instanceof expected_error)) {
760→ throw_error("unexpected exception type");
761→ return;
762→ }
763→ check_error_pos(e, expected_error, tab[1], tab[2], level);
764→ }
765→ if (!err) {
766→ throw_error("expected exception");
767→ }
768→}
769→
770→var poisoned_number = {
771→ valueOf: function() { throw Error("poisoned number") },
772→};
773→
774→function test_line_column_numbers()
775→{
776→ var f, e, tab;
777→
778→ /* The '@' character provides the expected position of the
779→ error. It is removed before evaluating the string. */
780→
781→ /* parsing */
782→ eval_error("\n 123 @a ", SyntaxError);
783→ eval_error("\n @/* ", SyntaxError);
784→ eval_error("function f @a", SyntaxError);
785→ /* currently regexp syntax errors point to the start of the regexp */
786→ eval_error("\n @/aaa]/u", SyntaxError);
787→
788→ /* function definitions */
789→/*
790→ tab = get_string_pos("\n @function f() { }; f;");
791→ e = (1, eval)(tab[0]);
792→ assert(e.lineNumber, tab[1]);
793→ assert(e.columnNumber, tab[2]);
794→*/
795→ /* errors */
796→ tab = get_string_pos('\n Error@("hello");');
797→ e = (1, eval)(tab[0]);
798→ check_error_pos(e, Error, tab[1], tab[2]);
799→
800→ eval_error('\n throw Error@("hello");', Error);
801→
802→ /* operators */
803→ eval_error('\n 1 + 2 @* poisoned_number;', Error, 1);
804→ eval_error('\n 1 + "café" @* poisoned_number;', Error, 1);
805→ eval_error('\n 1 + 2 @** poisoned_number;', Error, 1);
806→ eval_error('\n 2 * @+ poisoned_number;', Error, 1);
807→ eval_error('\n 2 * @- poisoned_number;', Error, 1);
808→ eval_error('\n 2 * @~ poisoned_number;', Error, 1);
809→ eval_error('\n 2 * @++ poisoned_number;', Error, 1);
810→ eval_error('\n 2 * @-- poisoned_number;', Error, 1);
811→ eval_error('\n 2 * poisoned_number @++;', Error, 1);
812→ eval_error('\n 2 * poisoned_number @--;', Error, 1);
813→
814→ /* accessors */
815→ eval_error('\n 1 + null@[0];', TypeError);
816→ eval_error('\n 1 + null @. abcd;', TypeError);
817→ // eval_error('\n 1 + null @( 1234 );', TypeError);
818→ eval_error('var obj = { get a() { throw Error("test"); } }\n 1 + obj @. a;',
819→ Error, 1);
820→ eval_error('var obj = { set a(b) { throw Error("test"); } }\n obj @. a = 1;',
821→ Error, 1);
822→
823→ /* variables reference */
824→ eval_error('\n 1 + @not_def', ReferenceError, 0);
825→
826→ /* assignments */
827→ eval_error('1 + (@not_def = 1)', ReferenceError, 0);
828→ eval_error('1 + (@not_def += 2)', ReferenceError, 0);
829→ eval_error('var a;\n 1 + (a @+= poisoned_number);', Error, 1);
830→}
831→
832→test();
833→test_string();
834→test_string2();
835→test_array();
836→test_array_ext();
837→test_enum();
838→test_function();
839→test_number();
840→test_math();
841→test_typed_array();
842→test_global_eval();
843→test_json();
844→test_regexp();
845→test_line_column_numbers();
846→test_large_eval_parse_stack();
847→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
1→/* test for example.c */
2→
3→function assert(actual, expected, message) {
4→ function get_full_type(o) {
5→ var type = typeof(o);
6→ if (type === 'object') {
7→ if (o === null)
8→ return 'null';
9→ if (o.constructor && o.constructor.name)
10→ return o.constructor.name;
11→ }
12→ return type;
13→ }
14→
15→ if (arguments.length == 1)
16→ expected = true;
17→
18→ if (typeof actual === typeof expected) {
19→ if (actual === expected) {
20→ if (actual !== 0 || (1 / actual) === (1 / expected))
21→ return;
22→ }
23→ if (typeof actual === 'number') {
24→ if (isNaN(actual) && isNaN(expected))
25→ return true;
26→ }
27→ if (typeof actual === 'object') {
28→ if (actual !== null && expected !== null
29→ && actual.constructor === expected.constructor
30→ && actual.toString() === expected.toString())
31→ return;
32→ }
33→ }
34→ // Should output the source file and line number and extract
35→ // the expression from the assert call
36→ throw Error("assertion failed: got " +
37→ get_full_type(actual) + ":|" + actual + "|, expected " +
38→ get_full_type(expected) + ":|" + expected + "|" +
39→ (message ? " (" + message + ")" : ""));
40→}
41→
42→function cb(param)
43→{
44→ return "test" + param;
45→}
46→
47→function test()
48→{
49→ var r1, r2, func;
50→ r1 = new Rectangle(100, 200);
51→ assert(r1.x, 100);
52→ assert(r1.y, 200);
53→
54→ /* test inheritance */
55→ r2 = new FilledRectangle(100, 200, 0x123456);
56→ assert(r2.x, 100);
57→ assert(r2.y, 200);
58→ assert(r2.color, 0x123456);
59→
60→ /* test closure */
61→ func = Rectangle.getClosure("abcd");
62→ assert(func(), "abcd");
63→
64→ /* test function call */
65→ assert(Rectangle.call(cb, "abc"), "testabc");
66→}
67→
68→test();
69→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
1→/* Mandelbrot display on a color terminal
2→ (c) 2025 Fabrice Bellard
3→ MIT license
4→*/
5→function mandelbrot(center_x, center_y, scale, w, h, max_it)
6→{
7→ var x1, y1, y2, i, x, y, cx, cy, fx, fy, i, t, c, s, c0;
8→ var colors = [ 14, 15, 7, 8, 0, 4, 12, 5, 13, 1, 9, 3, 11, 10, 2, 6];
9→ fx = scale * 0.5 / Math.min(w, h);
10→ fy = fx * 2;
11→ for(y1 = 0; y1 < h; y1++) {
12→ s = "";
13→ for(x1 = 0; x1 < w; x1++) {
14→ for(y2 = 0; y2 < 2; y2++) {
15→ cx = (x1 - w * 0.5) * fx + center_x;
16→ cy = (y1 + y2 * 0.5 - h * 0.5) * fy + center_y;
17→ x = 0;
18→ y = 0;
19→ for(i = 0; i < max_it && x * x + y * y < 4; i++) {
20→ t = x * x - y * y + cx;
21→ y = 2 * x * y + cy;
22→ x = t;
23→ }
24→ if (i >= max_it) {
25→ c = 0;
26→ } else {
27→ c = colors[i % colors.length];
28→ }
29→ if (y2 == 0)
30→ c0 = c;
31→ }
32→ s += "\x1b[" + (c0 >= 8 ? 82 + c0 : 30 + c0) + ";" + (c >= 8 ? 92 + c : 40 + c) + "m\u2580";
33→ }
34→ s += "\x1b[0m"; /* reset the colors */
35→ console.log(s);
36→ }
37→}
38→
39→mandelbrot(-0.75, 0.0, 2.0, 80, 25, 50);
40→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
1→/*
2→ * Javascript Micro benchmark
3→ *
4→ * Copyright (c) 2017-2019 Fabrice Bellard
5→ * Copyright (c) 2017-2019 Charlie Gordon
6→ *
7→ * Permission is hereby granted, free of charge, to any person obtaining a copy
8→ * of this software and associated documentation files (the "Software"), to deal
9→ * in the Software without restriction, including without limitation the rights
10→ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11→ * copies of the Software, and to permit persons to whom the Software is
12→ * furnished to do so, subject to the following conditions:
13→ *
14→ * The above copyright notice and this permission notice shall be included in
15→ * all copies or substantial portions of the Software.
16→ *
17→ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18→ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19→ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20→ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21→ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22→ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23→ * THE SOFTWARE.
24→ */
25→
26→function pad(str, n) {
27→ str += "";
28→ while (str.length < n)
29→ str += " ";
30→ return str;
31→}
32→
33→function pad_left(str, n) {
34→ str += "";
35→ while (str.length < n)
36→ str = " " + str;
37→ return str;
38→}
39→
40→function pad_center(str, n) {
41→ str += "";
42→ while (str.length < n) {
43→ if ((n - str.length) & 1)
44→ str = str + " ";
45→ else
46→ str = " " + str;
47→ }
48→ return str;
49→}
50→
51→var ref_data;
52→var log_data;
53→
54→var heads = [ "TEST", "N", "TIME (ns)", "REF (ns)", "SCORE (%)" ];
55→var widths = [ 22, 10, 9, 9, 9 ];
56→var precs = [ 0, 0, 2, 2, 2 ];
57→var total = [ 0, 0, 0, 0, 0 ];
58→var total_score = 0;
59→var total_scale = 0;
60→
61→if (typeof console == "undefined") {
62→ var console = { log: print };
63→}
64→
65→function log_line() {
66→ var i, n, s, a;
67→ s = "";
68→ for (i = 0, n = arguments.length; i < n; i++) {
69→ if (i > 0)
70→ s += " ";
71→ a = arguments[i];
72→ if (typeof a == "number") {
73→ total[i] += a;
74→ a = a.toFixed(precs[i]);
75→ a+="";
76→ s += pad_left(a, widths[i]);
77→ } else {
78→ s += pad_left(a, widths[i]);
79→ }
80→ }
81→ console.log(s);
82→}
83→
84→var clocks_per_sec = 1000;
85→var max_iterations = 10;
86→var clock_threshold = 100; /* favoring short measuring spans */
87→var min_n_argument = 1;
88→var get_clock;
89→if (typeof performance != "undefined")
90→ get_clock = performance.now;
91→else
92→ get_clock = Date.now;
93→
94→function log_one(text, n, ti) {
95→ var ref;
96→
97→ if (ref_data)
98→ ref = ref_data[text];
99→ else
100→ ref = null;
101→
102→ // XXX
103→ // ti = Math.round(ti * 100) / 100;
104→ log_data[text] = ti;
105→ if (typeof ref === "number") {
106→ log_line(text, n, ti, ref, ti * 100 / ref);
107→ total_score += ti * 100 / ref;
108→ total_scale += 100;
109→ } else {
110→ log_line(text, n, ti);
111→ total_score += 100;
112→ total_scale += 100;
113→ }
114→}
115→
116→function bench(f, text)
117→{
118→ var i, j, n, t, t1, ti, nb_its, ref, ti_n, ti_n1, min_ti;
119→
120→ nb_its = n = 1;
121→ if (f.bench) {
122→ ti_n = f(text);
123→ } else {
124→ ti_n = 1000000000;
125→ min_ti = clock_threshold / 10;
126→ for(i = 0; i < 30; i++) {
127→// print("n=", n);
128→ ti = 1000000000;
129→ for (j = 0; j < max_iterations; j++) {
130→ t = get_clock();
131→ while ((t1 = get_clock()) == t)
132→ continue;
133→ nb_its = f(n);
134→ if (nb_its < 0)
135→ return; // test failure
136→ t1 = get_clock() - t1;
137→ if (ti > t1)
138→ ti = t1;
139→ }
140→ if (ti >= min_ti) {
141→ ti_n1 = ti / nb_its;
142→ if (ti_n > ti_n1)
143→ ti_n = ti_n1;
144→ }
145→ if (ti >= clock_threshold && n >= min_n_argument)
146→ break;
147→ n = n * [ 2, 2.5, 2 ][i % 3];
148→ }
149→ // to use only the best timing from the last loop, uncomment below
150→ //ti_n = ti / nb_its;
151→ }
152→ /* nano seconds per iteration */
153→ log_one(text, n, ti_n * 1e9 / clocks_per_sec);
154→}
155→
156→var global_res; /* to be sure the code is not optimized */
157→
158→function empty_loop(n) {
159→ var j;
160→ for(j = 0; j < n; j++) {
161→ }
162→ return n;
163→}
164→
165→function date_now(n) {
166→ var j;
167→ for(j = 0; j < n; j++) {
168→ Date.now();
169→ }
170→ return n;
171→}
172→
173→function prop_read(n)
174→{
175→ var obj, sum, j;
176→ obj = {a: 1, b: 2, c:3, d:4 };
177→ sum = 0;
178→ for(j = 0; j < n; j++) {
179→ sum += obj.a;
180→ sum += obj.b;
181→ sum += obj.c;
182→ sum += obj.d;
183→ }
184→ global_res = sum;
185→ return n * 4;
186→}
187→
188→function prop_write(n)
189→{
190→ var obj, j;
191→ obj = {a: 1, b: 2, c:3, d:4 };
192→ for(j = 0; j < n; j++) {
193→ obj.a = j;
194→ obj.b = j;
195→ obj.c = j;
196→ obj.d = j;
197→ }
198→ return n * 4;
199→}
200→
201→function prop_update(n)
202→{
203→ var obj, j;
204→ obj = {a: 1, b: 2, c:3, d:4 };
205→ for(j = 0; j < n; j++) {
206→ obj.a += j;
207→ obj.b += j;
208→ obj.c += j;
209→ obj.d += j;
210→ }
211→ return n * 4;
212→}
213→
214→function prop_create(n)
215→{
216→ var obj, i, j;
217→ for(j = 0; j < n; j++) {
218→ obj = {};
219→ obj.a = 1;
220→ obj.b = 2;
221→ obj.c = 3;
222→ obj.d = 4;
223→ obj.e = 5;
224→ obj.f = 6;
225→ obj.g = 7;
226→ obj.h = 8;
227→ obj.i = 9;
228→ obj.j = 10;
229→ for(i = 0; i < 10; i++) {
230→ obj[i] = i;
231→ }
232→ }
233→ return n * 20;
234→}
235→
236→function prop_delete(n)
237→{
238→ var obj, j, i, len;
239→ len = 1000;
240→ obj = {};
241→ for(i = 0; i < n; i++) {
242→ for(j = 0; j < len; j++) {
243→ obj[j] = 1;
244→ }
245→ for(j = 0; j < len; j++) {
246→ delete obj[j];
247→ }
248→ }
249→ return n * len;
250→}
251→
252→function array_read(n)
253→{
254→ var tab, len, sum, i, j;
255→ tab = [];
256→ len = 10;
257→ for(i = 0; i < len; i++)
258→ tab[i] = i;
259→ sum = 0;
260→ for(j = 0; j < n; j++) {
261→ sum += tab[0];
262→ sum += tab[1];
263→ sum += tab[2];
264→ sum += tab[3];
265→ sum += tab[4];
266→ sum += tab[5];
267→ sum += tab[6];
268→ sum += tab[7];
269→ sum += tab[8];
270→ sum += tab[9];
271→ }
272→ global_res = sum;
273→ return len * n;
274→}
275→
276→function array_write(n)
277→{
278→ var tab, len, i, j;
279→ tab = [];
280→ len = 10;
281→ for(i = 0; i < len; i++)
282→ tab[i] = i;
283→ for(j = 0; j < n; j++) {
284→ tab[0] = j;
285→ tab[1] = j;
286→ tab[2] = j;
287→ tab[3] = j;
288→ tab[4] = j;
289→ tab[5] = j;
290→ tab[6] = j;
291→ tab[7] = j;
292→ tab[8] = j;
293→ tab[9] = j;
294→ }
295→ return len * n;
296→}
297→
298→function array_update(n)
299→{
300→ var tab, len, i, j;
301→ tab = [];
302→ len = 10;
303→ for(i = 0; i < len; i++)
304→ tab[i] = i;
305→ for(j = 0; j < n; j++) {
306→ tab[0] += j;
307→ tab[1] += j;
308→ tab[2] += j;
309→ tab[3] += j;
310→ tab[4] += j;
311→ tab[5] += j;
312→ tab[6] += j;
313→ tab[7] += j;
314→ tab[8] += j;
315→ tab[9] += j;
316→ }
317→ return len * n;
318→}
319→
320→function array_prop_create(n)
321→{
322→ var tab, i, j, len;
323→ len = 1000;
324→ for(j = 0; j < n; j++) {
325→ tab = [];
326→ for(i = 0; i < len; i++)
327→ tab[i] = i;
328→ }
329→ return len * n;
330→}
331→
332→function array_length_read(n)
333→{
334→ var tab, sum, j;
335→ tab = [1, 2, 3];
336→ sum = 0;
337→ for(j = 0; j < n; j++) {
338→ sum += tab.length;
339→ sum += tab.length;
340→ sum += tab.length;
341→ sum += tab.length;
342→ }
343→ global_res = sum;
344→ return n * 4;
345→}
346→
347→function array_length_decr(n)
348→{
349→ var tab, i, j, len;
350→ len = 1000;
351→ for(j = 0; j < n; j++) {
352→ tab = [];
353→ for(i = 0; i < len; i++)
354→ tab[i] = i;
355→ for(i = len - 1; i >= 0; i--)
356→ tab.length = i;
357→ }
358→ return len * n;
359→}
360→
361→function array_hole_length_decr(n)
362→{
363→ var tab, i, j, len;
364→ len = 1000;
365→ tab = [];
366→ for(i = 0; i < len; i++) {
367→ if (i != 3)
368→ tab[i] = i;
369→ }
370→ for(j = 0; j < n; j++) {
371→ for(i = len - 1; i >= 0; i--)
372→ tab.length = i;
373→ }
374→ return len * n;
375→}
376→
377→function array_push(n)
378→{
379→ var tab, i, j, len;
380→ len = 500;
381→ for(j = 0; j < n; j++) {
382→ tab = [];
383→ for(i = 0; i < len; i++)
384→ tab.push(i);
385→ }
386→ return len * n;
387→}
388→
389→function array_pop(n)
390→{
391→ var tab, ref, i, j, len, sum;
392→ len = 500;
393→ ref = [];
394→ for(i = 0; i < len; i++)
395→ ref[i] = i;
396→ for(j = 0; j < n; j++) {
397→ tab = ref.slice();
398→ sum = 0;
399→ for(i = 0; i < len; i++)
400→ sum += tab.pop();
401→ global_res = sum;
402→ }
403→ return len * n;
404→}
405→
406→function typed_array_read(n)
407→{
408→ var tab, len, sum, i, j;
409→ len = 10;
410→ tab = new Int32Array(len);
411→ for(i = 0; i < len; i++)
412→ tab[i] = i;
413→ sum = 0;
414→ for(j = 0; j < n; j++) {
415→ sum += tab[0];
416→ sum += tab[1];
417→ sum += tab[2];
418→ sum += tab[3];
419→ sum += tab[4];
420→ sum += tab[5];
421→ sum += tab[6];
422→ sum += tab[7];
423→ sum += tab[8];
424→ sum += tab[9];
425→ }
426→ global_res = sum;
427→ return len * n;
428→}
429→
430→function typed_array_write(n)
431→{
432→ var tab, len, i, j;
433→ len = 10;
434→ tab = new Int32Array(len);
435→ for(i = 0; i < len; i++)
436→ tab[i] = i;
437→ for(j = 0; j < n; j++) {
438→ tab[0] = j;
439→ tab[1] = j;
440→ tab[2] = j;
441→ tab[3] = j;
442→ tab[4] = j;
443→ tab[5] = j;
444→ tab[6] = j;
445→ tab[7] = j;
446→ tab[8] = j;
447→ tab[9] = j;
448→ }
449→ return len * n;
450→}
451→
452→function closure_read(n)
453→{
454→ function f(n) {
455→ var sum, j;
456→ var0 = 0;
457→ sum = 0;
458→ for(j = 0; j < n; j++) {
459→ sum += var0;
460→ sum += var0;
461→ sum += var0;
462→ sum += var0;
463→ }
464→ global_res = sum;
465→ }
466→ var var0 = 0;
467→ f(n);
468→ return n * 4;
469→}
470→
471→function closure_write(n)
472→{
473→ function f(n) {
474→ var j;
475→ for(j = 0; j < n; j++) {
476→ var0 = j;
477→ var0 = j;
478→ var0 = j;
479→ var0 = j;
480→ }
481→ }
482→ var var0;
483→
484→ f(n);
485→ return n * 4;
486→}
487→
488→var global_var0;
489→
490→function global_read(n)
491→{
492→ var sum, j;
493→ global_var0 = 0;
494→ sum = 0;
495→ for(j = 0; j < n; j++) {
496→ sum += global_var0;
497→ sum += global_var0;
498→ sum += global_var0;
499→ sum += global_var0;
500→ }
501→ global_res = sum;
502→ return n * 4;
503→}
504→
505→function global_write_strict(n)
506→{
507→ var j;
508→ for(j = 0; j < n; j++) {
509→ global_var0 = j;
510→ global_var0 = j;
511→ global_var0 = j;
512→ global_var0 = j;
513→ }
514→ return n * 4;
515→}
516→
517→function func_call(n)
518→{
519→ function f(a)
520→ {
521→ return 1;
522→ }
523→
524→ var j, sum;
525→ sum = 0;
526→ for(j = 0; j < n; j++) {
527→ sum += f(j);
528→ sum += f(j);
529→ sum += f(j);
530→ sum += f(j);
531→ }
532→ global_res = sum;
533→ return n * 4;
534→}
535→
536→function closure_var(n)
537→{
538→ function f(a)
539→ {
540→ sum++;
541→ }
542→
543→ var j, sum;
544→ sum = 0;
545→ for(j = 0; j < n; j++) {
546→ f(j);
547→ f(j);
548→ f(j);
549→ f(j);
550→ }
551→ global_res = sum;
552→ return n * 4;
553→}
554→
555→function int_arith(n)
556→{
557→ var i, j, sum;
558→ global_res = 0;
559→ for(j = 0; j < n; j++) {
560→ sum = 0;
561→ for(i = 0; i < 1000; i++) {
562→ sum += i * i;
563→ }
564→ global_res += sum;
565→ }
566→ return n * 1000;
567→}
568→
569→function float_arith(n)
570→{
571→ var i, j, sum, a, incr, a0;
572→ global_res = 0;
573→ a0 = 0.1;
574→ incr = 1.1;
575→ for(j = 0; j < n; j++) {
576→ sum = 0;
577→ a = a0;
578→ for(i = 0; i < 1000; i++) {
579→ sum += a * a;
580→ a += incr;
581→ }
582→ global_res += sum;
583→ }
584→ return n * 1000;
585→}
586→
587→function bigfloat_arith(n)
588→{
589→ var i, j, sum, a, incr, a0;
590→ global_res = 0;
591→ a0 = BigFloat("0.1");
592→ incr = BigFloat("1.1");
593→ for(j = 0; j < n; j++) {
594→ sum = 0;
595→ a = a0;
596→ for(i = 0; i < 1000; i++) {
597→ sum += a * a;
598→ a += incr;
599→ }
600→ global_res += sum;
601→ }
602→ return n * 1000;
603→}
604→
605→function bigint_arith(n, bits)
606→{
607→ var i, j, sum, a, incr, a0, sum0;
608→ sum0 = global_res = BigInt(0);
609→ a0 = BigInt(1) << BigInt(Math.floor((bits - 10) * 0.5));
610→ incr = BigInt(1);
611→ for(j = 0; j < n; j++) {
612→ sum = sum0;
613→ a = a0;
614→ for(i = 0; i < 1000; i++) {
615→ sum += a * a;
616→ a += incr;
617→ }
618→ global_res += sum;
619→ }
620→ return n * 1000;
621→}
622→
623→function bigint64_arith(n)
624→{
625→ return bigint_arith(n, 64);
626→}
627→
628→function bigint256_arith(n)
629→{
630→ return bigint_arith(n, 256);
631→}
632→
633→function set_collection_add(n)
634→{
635→ var s, i, j, len = 100;
636→ s = new Set();
637→ for(j = 0; j < n; j++) {
638→ for(i = 0; i < len; i++) {
639→ s.add(String(i), i);
640→ }
641→ for(i = 0; i < len; i++) {
642→ if (!s.has(String(i)))
643→ throw Error("bug in Set");
644→ }
645→ }
646→ return n * len;
647→}
648→
649→function array_for(n)
650→{
651→ var r, i, j, sum;
652→ r = [];
653→ for(i = 0; i < 100; i++)
654→ r[i] = i;
655→ for(j = 0; j < n; j++) {
656→ sum = 0;
657→ for(i = 0; i < 100; i++) {
658→ sum += r[i];
659→ }
660→ global_res = sum;
661→ }
662→ return n * 100;
663→}
664→
665→function array_for_in(n)
666→{
667→ var r, i, j, sum;
668→ r = [];
669→ for(i = 0; i < 100; i++)
670→ r[i] = i;
671→ for(j = 0; j < n; j++) {
672→ sum = 0;
673→ for(i in r) {
674→ sum += r[i];
675→ }
676→ global_res = sum;
677→ }
678→ return n * 100;
679→}
680→
681→function array_for_of(n)
682→{
683→ var r, i, j, sum;
684→ r = [];
685→ for(i = 0; i < 100; i++)
686→ r[i] = i;
687→ for(j = 0; j < n; j++) {
688→ sum = 0;
689→ for(i of r) {
690→ sum += i;
691→ }
692→ global_res = sum;
693→ }
694→ return n * 100;
695→}
696→
697→function math_min(n)
698→{
699→ var i, j, r;
700→ r = 0;
701→ for(j = 0; j < n; j++) {
702→ for(i = 0; i < 1000; i++)
703→ r = Math.min(i, 500);
704→ global_res = r;
705→ }
706→ return n * 1000;
707→}
708→
709→function regexp_ascii(n)
710→{
711→ var i, j, r, s;
712→ s = "the quick brown fox jumped over the lazy dog"
713→ for(j = 0; j < n; j++) {
714→ for(i = 0; i < 1000; i++)
715→ r = /the quick brown fox/.exec(s)
716→ global_res = r;
717→ }
718→ return n * 1000;
719→}
720→
721→function regexp_utf16(n)
722→{
723→ var i, j, r, s;
724→ s = "the quick brown ᶠᵒˣ jumped over the lazy ᵈᵒᵍ"
725→ for(j = 0; j < n; j++) {
726→ for(i = 0; i < 1000; i++)
727→ r = /the quick brown ᶠᵒˣ/.exec(s)
728→ global_res = r;
729→ }
730→ return n * 1000;
731→}
732→
733→function regexp_replace(n)
734→{
735→ var i, j, r, s;
736→ s = "the quick abc brown fox jumped abc over the lazy dog"
737→ for(j = 0; j < n; j++) {
738→ for(i = 0; i < 1000; i++)
739→ r = s.replace(/abc /g, "-");
740→ global_res = r;
741→ }
742→ return n * 1000;
743→}
744→
745→function string_length(n)
746→{
747→ var str, sum, j;
748→ str = "abcde";
749→ sum = 0;
750→ for(j = 0; j < n; j++) {
751→ sum += str.length;
752→ sum += str.length;
753→ sum += str.length;
754→ sum += str.length;
755→ }
756→ global_res = sum;
757→ return n * 4;
758→}
759→
760→/* incremental string contruction as local var */
761→function string_build1(n)
762→{
763→ var i, j, r;
764→ r = "";
765→ for(j = 0; j < n; j++) {
766→ for(i = 0; i < 100; i++)
767→ r += "x";
768→ global_res = r;
769→ }
770→ return n * 100;
771→}
772→
773→/* incremental string contruction as arg */
774→function string_build2(n, r)
775→{
776→ var i, j;
777→ r = "";
778→ for(j = 0; j < n; j++) {
779→ for(i = 0; i < 100; i++)
780→ r += "x";
781→ global_res = r;
782→ }
783→ return n * 100;
784→}
785→
786→/* incremental string contruction by prepending */
787→function string_build3(n, r)
788→{
789→ var i, j;
790→ r = "";
791→ for(j = 0; j < n; j++) {
792→ for(i = 0; i < 100; i++)
793→ r = "x" + r;
794→ global_res = r;
795→ }
796→ return n * 100;
797→}
798→
799→/* incremental string contruction with multiple reference */
800→function string_build4(n)
801→{
802→ var i, j, r, s;
803→ r = "";
804→ for(j = 0; j < n; j++) {
805→ for(i = 0; i < 100; i++) {
806→ s = r;
807→ r += "x";
808→ }
809→ global_res = r;
810→ }
811→ return n * 100;
812→}
813→
814→/* sort bench */
815→
816→function sort_bench(text) {
817→ function random(arr, n, def) {
818→ for (var i = 0; i < n; i++)
819→ arr[i] = def[(Math.random() * n) >> 0];
820→ }
821→ function random8(arr, n, def) {
822→ for (var i = 0; i < n; i++)
823→ arr[i] = def[(Math.random() * 256) >> 0];
824→ }
825→ function random1(arr, n, def) {
826→ for (var i = 0; i < n; i++)
827→ arr[i] = def[(Math.random() * 2) >> 0];
828→ }
829→ function hill(arr, n, def) {
830→ var mid = n >> 1;
831→ for (var i = 0; i < mid; i++)
832→ arr[i] = def[i];
833→ for (var i = mid; i < n; i++)
834→ arr[i] = def[n - i];
835→ }
836→ function comb(arr, n, def) {
837→ for (var i = 0; i < n; i++)
838→ arr[i] = def[(i & 1) * i];
839→ }
840→ function crisscross(arr, n, def) {
841→ for (var i = 0; i < n; i++)
842→ arr[i] = def[(i & 1) ? n - i : i];
843→ }
844→ function zero(arr, n, def) {
845→ for (var i = 0; i < n; i++)
846→ arr[i] = def[0];
847→ }
848→ function increasing(arr, n, def) {
849→ for (var i = 0; i < n; i++)
850→ arr[i] = def[i];
851→ }
852→ function decreasing(arr, n, def) {
853→ for (var i = 0; i < n; i++)
854→ arr[i] = def[n - 1 - i];
855→ }
856→ function alternate(arr, n, def) {
857→ for (var i = 0; i < n; i++)
858→ arr[i] = def[i ^ 1];
859→ }
860→ function jigsaw(arr, n, def) {
861→ for (var i = 0; i < n; i++)
862→ arr[i] = def[i % (n >> 4)];
863→ }
864→ function incbutone(arr, n, def) {
865→ for (var i = 0; i < n; i++)
866→ arr[i] = def[i];
867→ if (n > 0)
868→ arr[n >> 2] = def[n];
869→ }
870→ function incbutfirst(arr, n, def) {
871→ if (n > 0)
872→ arr[0] = def[n];
873→ for (var i = 1; i < n; i++)
874→ arr[i] = def[i];
875→ }
876→ function incbutlast(arr, n, def) {
877→ for (var i = 0; i < n - 1; i++)
878→ arr[i] = def[i + 1];
879→ if (n > 0)
880→ arr[n - 1] = def[0];
881→ }
882→
883→ var sort_cases = [ random, random8, random1, jigsaw, hill, comb,
884→ crisscross, zero, increasing, decreasing, alternate,
885→ incbutone, incbutlast, incbutfirst ];
886→
887→ var n = sort_bench.array_size || 10000;
888→ var array_type = sort_bench.array_type || Array;
889→ var def, arr;
890→ var i, j, x, y;
891→ var total = 0;
892→
893→ var save_total_score = total_score;
894→ var save_total_scale = total_scale;
895→
896→ // initialize default sorted array (n + 1 elements)
897→ def = new array_type(n + 1);
898→ if (array_type == Array) {
899→ for (i = 0; i <= n; i++) {
900→ def[i] = i + "";
901→ }
902→ } else {
903→ for (i = 0; i <= n; i++) {
904→ def[i] = i;
905→ }
906→ }
907→ def.sort();
908→ for (var f of sort_cases) {
909→ var ti = 0, tx = 0;
910→ for (j = 0; j < 100; j++) {
911→ arr = new array_type(n);
912→ f(arr, n, def);
913→ var t1 = get_clock();
914→ arr.sort();
915→ t1 = get_clock() - t1;
916→ tx += t1;
917→ if (!ti || ti > t1)
918→ ti = t1;
919→ if (tx >= clocks_per_sec)
920→ break;
921→ }
922→ total += ti;
923→
924→ i = 0;
925→ x = arr[0];
926→ if (x !== void 0) {
927→ for (i = 1; i < n; i++) {
928→ y = arr[i];
929→ if (y === void 0)
930→ break;
931→ if (x > y)
932→ break;
933→ x = y;
934→ }
935→ }
936→ while (i < n && arr[i] === void 0)
937→ i++;
938→ if (i < n) {
939→ console.log("sort_bench: out of order error for " + f.name +
940→ " at offset " + (i - 1) +
941→ ": " + arr[i - 1] + " > " + arr[i]);
942→ }
943→ if (sort_bench.verbose)
944→ log_one("sort_" + f.name, n, ti, n * 100);
945→ }
946→ total_score = save_total_score;
947→ total_scale = save_total_scale;
948→ return total / n / 1000;
949→}
950→sort_bench.bench = true;
951→sort_bench.verbose = false;
952→
953→function int_to_string(n)
954→{
955→ var s, r, j;
956→ r = 0;
957→ for(j = 0; j < n; j++) {
958→ s = (j + 1).toString();
959→ }
960→ return n;
961→}
962→
963→function float_to_string(n)
964→{
965→ var s, r, j;
966→ r = 0;
967→ for(j = 0; j < n; j++) {
968→ s = (j + 0.1).toString();
969→ }
970→ return n;
971→}
972→
973→function string_to_int(n)
974→{
975→ var s, r, j;
976→ r = 0;
977→ s = "12345";
978→ r = 0;
979→ for(j = 0; j < n; j++) {
980→ r += (s | 0);
981→ }
982→ global_res = r;
983→ return n;
984→}
985→
986→function string_to_float(n)
987→{
988→ var s, r, j;
989→ r = 0;
990→ s = "12345.6";
991→ r = 0;
992→ for(j = 0; j < n; j++) {
993→ r -= s;
994→ }
995→ global_res = r;
996→ return n;
997→}
998→
999→function load_result(filename)
1000→{
1001→ var f, str, res;
1002→ if (typeof std === "undefined")
1003→ return null;
1004→ f = std.open(filename, "r");
1005→ if (!f)
1006→ return null;
1007→ str = f.readAsString();
1008→ res = JSON.parse(str);
1009→ f.close();
1010→ return res;
1011→}
1012→
1013→function save_result(filename, obj)
1014→{
1015→ var f;
1016→ if (typeof std === "undefined")
1017→ return;
1018→ f = std.open(filename, "w");
1019→ f.puts(JSON.stringify(obj, null, 2));
1020→ f.puts("\n");
1021→ f.close();
1022→}
1023→
1024→function main(argc, argv, g)
1025→{
1026→ var test_list = [
1027→ empty_loop,
1028→ date_now,
1029→ prop_read,
1030→ prop_write,
1031→ prop_update,
1032→ prop_create,
1033→ prop_delete,
1034→ array_read,
1035→ array_write,
1036→ array_update,
1037→ array_prop_create,
1038→ array_length_read,
1039→ array_length_decr,
1040→// array_hole_length_decr,
1041→ array_push,
1042→ array_pop,
1043→ typed_array_read,
1044→ typed_array_write,
1045→ closure_read,
1046→ closure_write,
1047→ global_read,
1048→ global_write_strict,
1049→ func_call,
1050→ closure_var,
1051→ int_arith,
1052→ float_arith,
1053→// set_collection_add,
1054→ array_for,
1055→ array_for_in,
1056→ array_for_of,
1057→ math_min,
1058→ regexp_ascii,
1059→ regexp_utf16,
1060→ regexp_replace,
1061→ string_length,
1062→ string_build1,
1063→ string_build2,
1064→ //string_build3,
1065→ //string_build4,
1066→ sort_bench,
1067→ int_to_string,
1068→ float_to_string,
1069→ string_to_int,
1070→ string_to_float,
1071→ ];
1072→ var tests = [];
1073→ var i, j, n, f, name, found;
1074→
1075→ if (typeof BigInt == "function") {
1076→ /* BigInt test */
1077→ test_list.push(bigint64_arith);
1078→ test_list.push(bigint256_arith);
1079→ }
1080→
1081→ for (i = 1; i < argc;) {
1082→ name = argv[i++];
1083→ if (name == "-a") {
1084→ sort_bench.verbose = true;
1085→ continue;
1086→ }
1087→ if (name == "-t") {
1088→ name = argv[i++];
1089→ sort_bench.array_type = g[name];
1090→ if (typeof sort_bench.array_type != "function") {
1091→ console.log("unknown array type: " + name);
1092→ return 1;
1093→ }
1094→ continue;
1095→ }
1096→ if (name == "-n") {
1097→ sort_bench.array_size = +argv[i++];
1098→ continue;
1099→ }
1100→ for (j = 0, found = false; j < test_list.length; j++) {
1101→ f = test_list[j];
1102→ if (f.name.slice(0, name.length) === name) {
1103→ tests.push(f);
1104→ found = true;
1105→ }
1106→ }
1107→ if (!found) {
1108→ console.log("unknown benchmark: " + name);
1109→ return 1;
1110→ }
1111→ }
1112→ if (tests.length == 0)
1113→ tests = test_list;
1114→
1115→ ref_data = load_result("microbench.txt");
1116→ log_data = {};
1117→ log_line.apply(null, heads);
1118→ n = 0;
1119→
1120→ for(i = 0; i < tests.length; i++) {
1121→ f = tests[i];
1122→ bench(f, f.name, ref_data, log_data);
1123→ if (ref_data && ref_data[f.name])
1124→ n++;
1125→ }
1126→ if (ref_data)
1127→ log_line("total", "", total[2], total[3], total_score * 100 / total_scale);
1128→ else
1129→ log_line("total", "", total[2]);
1130→
1131→ if (tests == test_list)
1132→ save_result("microbench-new.txt", log_data);
1133→}
1134→
1135→if (!scriptArgs)
1136→ scriptArgs = [];
1137→main(scriptArgs.length, scriptArgs, this);
1138→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
Now let me run each test and see where it fails to build a comprehensive todo list:
timeout 5 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
ctx.eval(open('tests/test_language.js').read())
" 2>&1 | head -30timeout 5 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
ctx.eval(open('tests/test_builtin.js').read())
" 2>&1 | head -30timeout 5 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
ctx.eval(open('tests/mandelbrot.js').read())
" 2>&1 | head -30Traceback (most recent call last):
File "<string>", line 4, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 591, in eval
ast = parser.parse()
^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 114, in parse
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 163, in _parse_statement
return self._parse_function_declaration()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 389, in _parse_function_declaration
body = self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 136, in _parse_statement
return self._parse_while_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 221, in _parse_while_statement
body = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 171, in _parse_statement
body = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 127, in _parse_statement
return self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statementTraceback (most recent call last):
File "<string>", line 4, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 603, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 106, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 163, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 506, in _execute_opcode
self._new_object(arg)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1629, in _new_object
raise JSTypeError(f"{constructor} is not a constructor")
mquickjs_python.errors.JSTypeError: TypeError: JSObject({'keys': <function JSContext._create_object_constructor.<locals>.keys_fn at 0x7ecabc598680>, 'values': <function JSContext._create_object_constructor.<locals>.values_fn at 0x7ecabc3c3f60>, 'entries': <function JSContext._create_object_constructor.<locals>.entries_fn at 0x7ecabc3d4ae0>, 'assign': <function JSContext._create_object_constructor.<locals>.assign_fn at 0x7ecabc3d4b80>}) is not a constructorExit code 143 Command timed out after 2m 0s Terminated 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Now I have a clearer picture of what's needed. Let me analyze:
test_language.js - Parser issue with labeled statements (e.g., while (1) label: break)
test_builtin.js - Object is not a constructor (needs new Object() support)
mandelbrot.js - Actually runs! It printed output but timed out after completing. The issue is console.log - looks like it works but the timeout is just the process limit.
test_rect.js - Uses Rectangle and FilledRectangle classes that don't exist (these would normally be provided by C bindings)
microbench.js - Uses many advanced features including performance.now, Date.now, TypedArrays, BigInt, Set, etc.
Let me create a todo list based on my analysis:
timeout 5 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test what specific feature fails in microbench
ctx.eval('''
var global_res;
function pad(str, n) {
str += \"\";
while (str.length < n)
str += \" \";
return str;
}
console.log(pad(\"test\", 10));
''')
" 2>&1timeout 5 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test labeled statements
ctx.eval('while (1) label: break')
print('labeled statement passed')
" 2>&1timeout 5 uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test new Object()
result = ctx.eval('new Object()')
print('new Object:', result)
" 2>&1Exit code 1
Traceback (most recent call last):
File "<string>", line 5, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 603, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 106, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 163, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 506, in _execute_opcode
self._new_object(arg)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1629, in _new_object
raise JSTypeError(f"{constructor} is not a constructor")
mquickjs_python.errors.JSTypeError: TypeError: JSObject({'keys': <function JSContext._create_object_constructor.<locals>.keys_fn at 0x7eb1d6ebc4a0>, 'values': <function JSContext._create_object_constructor.<locals>.values_fn at 0x7eb1d6aa7ec0>, 'entries': <function JSContext._create_object_constructor.<locals>.entries_fn at 0x7eb1d6ab8a40>, 'assign': <function JSContext._create_object_constructor.<locals>.assign_fn at 0x7eb1d6ab8ae0>}) is not a constructorNow I have a clearer picture. Let me create a comprehensive todo list for the remaining features:
Todos have been modified successfully. Ensure that you continue to use the todo list to track your progress. Please proceed with the current tasks if applicable
Here's the todo list for features needed by the remaining xfail tests:
test_language.js (parser/compiler):
1. Fix labeled statement parsing (while (1) label: break)
2. Add exponentiation operator (**)
3. Add bitwise operators (<<, >>, >>>, &, |, ^, ~)
4. Add instanceof operator
test_builtin.js (built-in objects):
1. Make Object/Array/Function callable as constructors (new Object())
2. Add Object.getPrototypeOf/setPrototypeOf
3. Add Object.defineProperty with getter/setter support
4. Add Object.create
5. Add Function constructor (new Function('a','b','return a+b'))
6. Add TypedArrays (Int32Array, Uint8Array, Uint8ClampedArray, etc.)
7. Add ArrayBuffer
8. Add Date.now()
9. Add String methods: codePointAt, fromCodePoint
10. Add Math methods: fround, imul, min
11. Add JSON.parse/stringify
12. Add eval() function
mandelbrot.js:
- Actually runs! Uses console.log and basic math. Just needs more time or is complete.
test_rect.js:
- Uses external Rectangle/FilledRectangle classes (C bindings) - not applicable
microbench.js:
- Needs most of the above features plus performance.now, BigInt, Set
The user wants me to implement all the missing features using TDD (test-driven development) and commit often. Let me start with the first item on the list: fixing labeled statement parsing.
Let me work through these systematically, writing a failing test first, then implementing the fix, then committing.
Let me start implementing these features one by one, TDD style. I'll begin with the simpler ones first.
Todos have been modified successfully. Ensure that you continue to use the todo list to track your progress. Please proceed with the current tasks if applicable
Let me start with the labeled statement parsing issue. The problem is while (1) label: break - a labeled statement after a while with no block. Let me write a failing test first:
class TestTryFinallyBreak:
"""Test that finally blocks execute before break/continue/return."""
def test_break_in_try_finally(self):
"""Break inside try should run finally block first."""
ctx = JSContext()
result = ctx.eval('''
var s = '';
for(;;) {
try {
s += 't';
break;
} finally {
s += 'f';
}
}
s
''')
assert result == "tf"class TestTryFinallyBreak:
"""Test that finally blocks execute before break/continue/return."""
def test_break_in_try_finally(self):
"""Break inside try should run finally block first."""
ctx = JSContext()
result = ctx.eval('''
var s = '';
for(;;) {
try {
s += 't';
break;
} finally {
s += 'f';
}
}
s
''')
assert result == "tf"
class TestLabeledStatements:
"""Test labeled statements."""
def test_labeled_break_after_while(self):
"""Labeled break after while without braces."""
ctx = JSContext()
# Should not hang - breaks immediately
result = ctx.eval("var x = 0; while (1) label: break; x")
assert result == 0
def test_labeled_break_in_block(self):
"""Labeled break in block."""
ctx = JSContext()
result = ctx.eval("var x = 0; label: { x = 1; break label; x = 2; } x")
assert result == 1<tool_use_error>File has not been read yet. Read it first before writing to it.</tool_use_error>
{
"file_path": "/home/user/mquickjs-python/tests/test_vm.py",
"limit": 30,
"offset": 400
} 400→ assert result == 20 # 10 * 2
401→
402→class TestTryFinallyBreak:
403→ """Test that finally blocks execute before break/continue/return."""
404→
405→ def test_break_in_try_finally(self):
406→ """Break inside try should run finally block first."""
407→ ctx = JSContext()
408→ result = ctx.eval('''
409→ var s = '';
410→ for(;;) {
411→ try {
412→ s += 't';
413→ break;
414→ } finally {
415→ s += 'f';
416→ }
417→ }
418→ s
419→ ''')
420→ assert result == "tf"
421→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
class TestTryFinallyBreak:
"""Test that finally blocks execute before break/continue/return."""
def test_break_in_try_finally(self):
"""Break inside try should run finally block first."""
ctx = JSContext()
result = ctx.eval('''
var s = '';
for(;;) {
try {
s += 't';
break;
} finally {
s += 'f';
}
}
s
''')
assert result == "tf"class TestTryFinallyBreak:
"""Test that finally blocks execute before break/continue/return."""
def test_break_in_try_finally(self):
"""Break inside try should run finally block first."""
ctx = JSContext()
result = ctx.eval('''
var s = '';
for(;;) {
try {
s += 't';
break;
} finally {
s += 'f';
}
}
s
''')
assert result == "tf"
class TestLabeledStatements:
"""Test labeled statements."""
def test_labeled_break_after_while(self):
"""Labeled break after while without braces."""
ctx = JSContext()
# Should not hang - breaks immediately
result = ctx.eval("var x = 0; while (1) label: break; x")
assert result == 0
def test_labeled_break_in_block(self):
"""Labeled break in block."""
ctx = JSContext()
result = ctx.eval("var x = 0; label: { x = 1; break label; x = 2; } x")
assert result == 1The file /home/user/mquickjs-python/tests/test_vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
398→ obj.value
399→ ''')
400→ assert result == 20 # 10 * 2
401→
402→class TestTryFinallyBreak:
403→ """Test that finally blocks execute before break/continue/return."""
404→
405→ def test_break_in_try_finally(self):
406→ """Break inside try should run finally block first."""
407→ ctx = JSContext()
408→ result = ctx.eval('''
409→ var s = '';
410→ for(;;) {
411→ try {
412→ s += 't';
413→ break;
414→ } finally {
415→ s += 'f';
416→ }
417→ }
418→ s
419→ ''')
420→ assert result == "tf"
421→
422→
423→class TestLabeledStatements:
424→ """Test labeled statements."""
425→
426→ def test_labeled_break_after_while(self):
427→ """Labeled break after while without braces."""
428→ ctx = JSContext()
429→ # Should not hang - breaks immediately
430→ result = ctx.eval("var x = 0; while (1) label: break; x")
431→ assert result == 0
432→
433→ def test_labeled_break_in_block(self):
434→ """Labeled break in block."""
435→ ctx = JSContext()
436→ result = ctx.eval("var x = 0; label: { x = 1; break label; x = 2; } x")
437→ assert result == 1
438→timeout 10 uv run pytest tests/test_vm.py::TestLabeledStatements -v 2>&1
Exit code 124 ============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python cachedir: .pytest_cache rootdir: /home/user/mquickjs-python configfile: pyproject.toml collecting ... collected 2 items tests/test_vm.py::TestLabeledStatements::test_labeled_break_after_while
The test hangs - it's an infinite loop because the break doesn't have a target. Let me look at the parser to understand how labeled statements are parsed:
{
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/parser.py",
"pattern": "LabeledStatement|labeled"
}18: SwitchStatement, SwitchCase, LabeledStatement, 165: # Check for labeled statement: IDENTIFIER COLON statement 167: # Look ahead for colon to detect labeled statement 172: return LabeledStatement(Identifier(label_token.value), body)
Let me look at the compiler to see how labeled statements are handled - the issue is that labeled breaks might not be working correctly:
{
"-C": 10,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"pattern": "LabeledStatement"
}6- Node, Program, NumericLiteral, StringLiteral, BooleanLiteral, NullLiteral, 7- RegexLiteral, Identifier, ThisExpression, ArrayExpression, ObjectExpression, Property, 8- UnaryExpression, UpdateExpression, BinaryExpression, LogicalExpression, 9- ConditionalExpression, AssignmentExpression, SequenceExpression, 10- MemberExpression, CallExpression, NewExpression, 11- ExpressionStatement, BlockStatement, EmptyStatement, 12- VariableDeclaration, VariableDeclarator, 13- IfStatement, WhileStatement, DoWhileStatement, ForStatement, 14- ForInStatement, ForOfStatement, BreakStatement, ContinueStatement, 15- ReturnStatement, ThrowStatement, TryStatement, CatchClause, 16: SwitchStatement, SwitchCase, LabeledStatement, 17- FunctionDeclaration, FunctionExpression, ArrowFunctionExpression, 18-) 19-from .opcodes import OpCode 20-from .values import UNDEFINED 21- 22- 23-@dataclass 24-class CompiledFunction: 25- """A compiled function.""" 26- name: str -- 211- elif isinstance(node, TryStatement): 212- visit(node.block) 213- if node.handler: 214- visit(node.handler.body) 215- if node.finalizer: 216- visit(node.finalizer) 217- elif isinstance(node, SwitchStatement): 218- for case in node.cases: 219- for stmt in case.consequent: 220- visit(stmt) 221: elif isinstance(node, LabeledStatement): 222- visit(node.body) 223- elif hasattr(node, '__dict__'): 224- # For expression nodes (e.g., arrow function expression body) 225- for value in node.__dict__.values(): 226- if isinstance(value, Node): 227- visit(value) 228- elif isinstance(value, list): 229- for item in value: 230- if isinstance(item, Node): 231- visit(item) -- 727- # Regular local 728- self._add_local(name) 729- slot = self._get_local(name) 730- self._emit(OpCode.STORE_LOCAL, slot) 731- else: 732- # At program level: use global variable 733- idx = self._add_name(name) 734- self._emit(OpCode.STORE_NAME, idx) 735- self._emit(OpCode.POP) 736- 737: elif isinstance(node, LabeledStatement): 738- # Create a loop context for the label 739- loop_ctx = LoopContext(label=node.label.name) 740- self.loop_stack.append(loop_ctx) 741- 742- # Compile the labeled body 743- self._compile_statement(node.body) 744- 745- # Patch break jumps that target this label 746- for pos in loop_ctx.break_jumps: 747- self._patch_jump(pos)
I see the issue now. When we have while (1) label: break;, the break targets the label, not the while loop. But the current implementation creates a LoopContext for the labeled statement, and break jumps to after the labeled statement. The problem is:
while (1) creates a LoopContextlabel: creates another LoopContextbreak (unlabeled) looks for the innermost LoopContext and finds label: not the while loopActually wait, let me re-read. The break is unlabeled, so it should target the innermost loop/switch, not a labeled statement. But the labeled statement creates a LoopContext with is_loop=True by default.
Looking at the code again:
- LoopContext(label=node.label.name) - this creates with is_loop=True by default
- For break, if unlabeled, it finds the innermost context
- The issue is that labeled statements are getting is_loop=True when they shouldn't
The LoopContext has is_loop: bool = True # False for switch statements (break only, no continue)
For a labeled statement that's NOT a loop (like label: break; or label: { ... }), we should use is_loop=False so that unlabeled break/continue skip over it.
Actually, looking at JavaScript semantics:
- break without a label targets the innermost loop or switch
- break label targets the labeled statement
But while (1) label: break; - the break here is unlabeled, so it should target the while loop, not the label. Let me fix the LabeledStatement handling:
I see the issue. Labeled statements are creating a LoopContext with is_loop=True, but they shouldn't be treated as loops for unlabeled breaks. Let me read more context:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 30,
"offset": 735
} 735→ self._emit(OpCode.POP)
736→
737→ elif isinstance(node, LabeledStatement):
738→ # Create a loop context for the label
739→ loop_ctx = LoopContext(label=node.label.name)
740→ self.loop_stack.append(loop_ctx)
741→
742→ # Compile the labeled body
743→ self._compile_statement(node.body)
744→
745→ # Patch break jumps that target this label
746→ for pos in loop_ctx.break_jumps:
747→ self._patch_jump(pos)
748→
749→ self.loop_stack.pop()
750→
751→ else:
752→ raise NotImplementedError(f"Cannot compile statement: {type(node).__name__}")
753→
754→ def _compile_statement_for_value(self, node: Node) -> None:
755→ """Compile a statement leaving its completion value on the stack.
756→
757→ This is used for eval semantics where the last statement's value is returned.
758→ """
759→ if isinstance(node, ExpressionStatement):
760→ # Expression statement: value is the expression's value
761→ self._compile_expression(node.expression)
762→
763→ elif isinstance(node, BlockStatement):
764→ # Block statement: value is the last statement's value
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see. The labeled statement creates LoopContext(label=node.label.name) with is_loop=True by default. When an unlabeled break is encountered, it looks for the innermost LoopContext - but labeled statements aren't loops!For while (1) label: break;:1. while (1) creates LoopContext(is_loop=True)
2. label: creates LoopContext(label="label", is_loop=True) - BUG: should be is_loop=False
3. break (unlabeled) looks for innermost LoopContext where is_loop=True, finds the label: context (wrong!)
4. break jumps to after the labeled statement, which is still inside the while loop5. Infinite loop!The fix is to set is_loop=False for LabeledStatement:
elif isinstance(node, LabeledStatement):
# Create a loop context for the label
loop_ctx = LoopContext(label=node.label.name)
self.loop_stack.append(loop_ctx) elif isinstance(node, LabeledStatement):
# Create a loop context for the label
# is_loop=False so unlabeled break/continue skip this context
loop_ctx = LoopContext(label=node.label.name, is_loop=False)
self.loop_stack.append(loop_ctx)The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 733→ idx = self._add_name(name) 734→ self._emit(OpCode.STORE_NAME, idx) 735→ self._emit(OpCode.POP) 736→ 737→ elif isinstance(node, LabeledStatement): 738→ # Create a loop context for the label 739→ # is_loop=False so unlabeled break/continue skip this context 740→ loop_ctx = LoopContext(label=node.label.name, is_loop=False) 741→ self.loop_stack.append(loop_ctx) 742→ 743→ # Compile the labeled body 744→ self._compile_statement(node.body) 745→
Now let me also check the break statement handling - it should look for is_loop=True or a matching label:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 30,
"offset": 555
} 555→ self._patch_jump(pos)
556→ for pos in loop_ctx.continue_jumps:
557→ self._patch_jump(pos, loop_start)
558→
559→ self.loop_stack.pop()
560→
561→ elif isinstance(node, BreakStatement):
562→ if not self.loop_stack:
563→ raise SyntaxError("'break' outside of loop")
564→
565→ # Find the right loop context (labeled or innermost)
566→ target_label = node.label.name if node.label else None
567→ ctx = None
568→ for loop_ctx in reversed(self.loop_stack):
569→ if target_label is None or loop_ctx.label == target_label:
570→ ctx = loop_ctx
571→ break
572→
573→ if ctx is None:
574→ raise SyntaxError(f"label '{target_label}' not found")
575→
576→ # Emit pending finally blocks before the break
577→ self._emit_pending_finally_blocks()
578→
579→ pos = self._emit_jump(OpCode.JUMP)
580→ ctx.break_jumps.append(pos)
581→
582→ elif isinstance(node, ContinueStatement):
583→ if not self.loop_stack:
584→ raise SyntaxError("'continue' outside of loop")
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see the issue now. For break without a label (target_label is None), we need to find an is_loop=True context. Currently the code just finds any context. Let me fix it:
elif isinstance(node, BreakStatement):
if not self.loop_stack:
raise SyntaxError("'break' outside of loop")
# Find the right loop context (labeled or innermost)
target_label = node.label.name if node.label else None
ctx = None
for loop_ctx in reversed(self.loop_stack):
if target_label is None or loop_ctx.label == target_label:
ctx = loop_ctx
break
if ctx is None:
raise SyntaxError(f"label '{target_label}' not found") elif isinstance(node, BreakStatement):
if not self.loop_stack:
raise SyntaxError("'break' outside of loop")
# Find the right loop context (labeled or innermost loop/switch)
target_label = node.label.name if node.label else None
ctx = None
for loop_ctx in reversed(self.loop_stack):
if target_label is not None:
# Labeled break - find the matching label
if loop_ctx.label == target_label:
ctx = loop_ctx
break
else:
# Unlabeled break - find innermost loop or switch (is_loop=True)
if loop_ctx.is_loop:
ctx = loop_ctx
break
if ctx is None:
if target_label:
raise SyntaxError(f"label '{target_label}' not found")
else:
raise SyntaxError("'break' outside of loop")The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
557→ self._patch_jump(pos, loop_start)
558→
559→ self.loop_stack.pop()
560→
561→ elif isinstance(node, BreakStatement):
562→ if not self.loop_stack:
563→ raise SyntaxError("'break' outside of loop")
564→
565→ # Find the right loop context (labeled or innermost loop/switch)
566→ target_label = node.label.name if node.label else None
567→ ctx = None
568→ for loop_ctx in reversed(self.loop_stack):
569→ if target_label is not None:
570→ # Labeled break - find the matching label
571→ if loop_ctx.label == target_label:
572→ ctx = loop_ctx
573→ break
574→ else:
575→ # Unlabeled break - find innermost loop or switch (is_loop=True)
576→ if loop_ctx.is_loop:
577→ ctx = loop_ctx
578→ break
579→
580→ if ctx is None:
581→ if target_label:
582→ raise SyntaxError(f"label '{target_label}' not found")
583→ else:
584→ raise SyntaxError("'break' outside of loop")
585→
586→ # Emit pending finally blocks before the break
587→ self._emit_pending_finally_blocks()
588→timeout 10 uv run pytest tests/test_vm.py::TestLabeledStatements -v 2>&1
============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python cachedir: .pytest_cache rootdir: /home/user/mquickjs-python configfile: pyproject.toml collecting ... collected 2 items tests/test_vm.py::TestLabeledStatements::test_labeled_break_after_while PASSED [ 50%] tests/test_vm.py::TestLabeledStatements::test_labeled_break_in_block PASSED [100%] ============================== 2 passed in 0.07s ===============================
Now let me run the full test suite to make sure I didn't break anything, then commit:
self._execute_opcode(op, arg, frame)
src/mquickjs_python/vm.py:514: in _execute_opcode
self._throw(exc)
src/mquickjs_python/vm.py:1652: in _throw
raise JSError(to_string(msg) if msg else "Error")
E mquickjs_python.errors.JSError: Error: assertion failed: got |false|, expected |true|
=========================== short test summary info ============================
FAILED tests/test_js_basic.py::test_basic_js[test_loop_switch.js-path8] - mqu...
!!!!!!!!!!!!!!!!!!!!!!!!!! stopping after 1 failures !!!!!!!!!!!!!!!!!!!!!!!!!!!
========================= 1 failed, 78 passed in 0.64s ========================= 1→function assert(actual, expected, message) {
2→ if (arguments.length == 1)
3→ expected = true;
4→
5→ if (actual === expected)
6→ return;
7→
8→ if (actual !== null && expected !== null
9→ && typeof actual == 'object' && typeof expected == 'object'
10→ && actual.toString() === expected.toString())
11→ return;
12→
13→ throw Error("assertion failed: got |" + actual + "|" +
14→ ", expected |" + expected + "|" +
15→ (message ? " (" + message + ")" : ""));
16→}
17→
18→function test_switch1()
19→{
20→ var i, a, s;
21→ s = "";
22→ for(i = 0; i < 3; i++) {
23→ a = "?";
24→ switch(i) {
25→ case 0:
26→ a = "a";
27→ break;
28→ case 1:
29→ a = "b";
30→ break;
31→ default:
32→ a = "c";
33→ break;
34→ }
35→ s += a;
36→ }
37→ assert(s === "abc" && i === 3);
38→}
39→
40→test_switch1();
41→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
The issue is that break inside a switch statement doesn't work anymore because switch has is_loop=False. But switch SHOULD be breakable. Let me check how switch is compiled:
{
"-C": 5,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"pattern": "SwitchStatement"
}11- ExpressionStatement, BlockStatement, EmptyStatement, 12- VariableDeclaration, VariableDeclarator, 13- IfStatement, WhileStatement, DoWhileStatement, ForStatement, 14- ForInStatement, ForOfStatement, BreakStatement, ContinueStatement, 15- ReturnStatement, ThrowStatement, TryStatement, CatchClause, 16: SwitchStatement, SwitchCase, LabeledStatement, 17- FunctionDeclaration, FunctionExpression, ArrowFunctionExpression, 18-) 19-from .opcodes import OpCode 20-from .values import UNDEFINED 21- -- 212- visit(node.block) 213- if node.handler: 214- visit(node.handler.body) 215- if node.finalizer: 216- visit(node.finalizer) 217: elif isinstance(node, SwitchStatement): 218- for case in node.cases: 219- for stmt in case.consequent: 220- visit(stmt) 221- elif isinstance(node, LabeledStatement): 222- visit(node.body) -- 668- # Normal finally block (after try completes normally or after catch) 669- self._patch_jump(jump_to_finally) 670- if node.finalizer: 671- self._compile_statement(node.finalizer) 672- 673: elif isinstance(node, SwitchStatement): 674- self._compile_expression(node.discriminant) 675- 676- jump_to_body: List[Tuple[int, int]] = [] 677- default_jump = None 678-
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 50,
"offset": 673
}673→ elif isinstance(node, SwitchStatement): 674→ self._compile_expression(node.discriminant) 675→ 676→ jump_to_body: List[Tuple[int, int]] = [] 677→ default_jump = None 678→ 679→ # Compile case tests 680→ for i, case in enumerate(node.cases): 681→ if case.test: 682→ self._emit(OpCode.DUP) 683→ self._compile_expression(case.test) 684→ self._emit(OpCode.SEQ) 685→ pos = self._emit_jump(OpCode.JUMP_IF_TRUE) 686→ jump_to_body.append((pos, i)) 687→ else: 688→ default_jump = (self._emit_jump(OpCode.JUMP), i) 689→ 690→ # Jump to end if no match 691→ jump_end = self._emit_jump(OpCode.JUMP) 692→ 693→ # Case bodies 694→ case_positions = [] 695→ loop_ctx = LoopContext(is_loop=False) # For break statements only 696→ self.loop_stack.append(loop_ctx) 697→ 698→ for i, case in enumerate(node.cases): 699→ case_positions.append(len(self.bytecode)) 700→ for stmt in case.consequent: 701→ self._compile_statement(stmt) 702→ 703→ self._patch_jump(jump_end) 704→ self._emit(OpCode.POP) # Pop discriminant 705→ 706→ # Patch jumps to case bodies 707→ for pos, idx in jump_to_body: 708→ self._patch_jump(pos, case_positions[idx]) 709→ if default_jump: 710→ pos, idx = default_jump 711→ self._patch_jump(pos, case_positions[idx]) 712→ 713→ # Patch break jumps 714→ for pos in loop_ctx.break_jumps: 715→ self._patch_jump(pos) 716→ 717→ self.loop_stack.pop() 718→ 719→ elif isinstance(node, FunctionDeclaration): 720→ # Compile function 721→ func = self._compile_function(node.id.name, node.params, node.body) 722→ func_idx = len(self.functions) <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
I see! The switch statement creates LoopContext(is_loop=False) which is correct (it's not a loop for continue), but my break logic now only looks for is_loop=True.The fix is: for break (not continue), we should accept is_loop=True (loops) OR is_loop=False if it's a switch statement. Actually the issue is more fundamental - is_loop=False means "break is allowed but continue is not". So I need to fix my logic:- For unlabeled break: find innermost context (regardless of is_loop)- For unlabeled continue: find innermost loop (where is_loop=True)Actually looking at the original code:pythonfor loop_ctx in reversed(self.loop_stack):
if target_label is None or loop_ctx.label == target_label:
ctx = loop_ctx
breakThis was finding ANY context. The problem was LabeledStatement with is_loop=True. But now I have:- LabeledStatement: is_loop=False- Switch: is_loop=False- Loops: is_loop=TrueSo for unlabeled break, we want to break out of:1. Loops (is_loop=True)
2. Switch statements (is_loop=False, but it's in the stack)3. NOT labeled statements (but they're also is_loop=False now)The issue is that switch and labeled statements both have is_loop=False. The difference is:- break inside switch should target the switch- break inside labeled statement should NOT target the labeled statement, but the enclosing loop/switchWait, actually break label CAN target a labeled statement. It's only UNLABELED break that should not.
So the issue is:- Labeled break (break label) targets the label
- Unlabeled break targets the innermost switch or loop (not a plain labeled statement)
But how do we distinguish between a labeled statement and a switch? They both have is_loop=False.I think the key insight is:
I can differentiate contexts by their label presence. An unlabeled break will skip labeled statements, targeting only loops or switch statements directly in the stack. This means checking both the is_loop flag and the label's existence becomes crucial for precise break behavior.
I see - switch has is_loop=False but it's a valid break target. The difference is:
- Switch: is_loop=False, no label
- LabeledStatement: is_loop=False, HAS a label
elif isinstance(node, BreakStatement):
if not self.loop_stack:
raise SyntaxError("'break' outside of loop")
# Find the right loop context (labeled or innermost loop/switch)
target_label = node.label.name if node.label else None
ctx = None
for loop_ctx in reversed(self.loop_stack):
if target_label is not None:
# Labeled break - find the matching label
if loop_ctx.label == target_label:
ctx = loop_ctx
break
else:
# Unlabeled break - find innermost loop or switch (is_loop=True)
if loop_ctx.is_loop:
ctx = loop_ctx
break
if ctx is None:
if target_label:
raise SyntaxError(f"label '{target_label}' not found")
else:
raise SyntaxError("'break' outside of loop") elif isinstance(node, BreakStatement):
if not self.loop_stack:
raise SyntaxError("'break' outside of loop")
# Find the right loop context (labeled or innermost loop/switch)
target_label = node.label.name if node.label else None
ctx = None
for loop_ctx in reversed(self.loop_stack):
if target_label is not None:
# Labeled break - find the matching label
if loop_ctx.label == target_label:
ctx = loop_ctx
break
else:
# Unlabeled break - find innermost loop or switch
# is_loop=True means it's a loop, is_loop=False with no label means switch
# Skip labeled statements (is_loop=False with label) for unlabeled break
if loop_ctx.is_loop or loop_ctx.label is None:
ctx = loop_ctx
break
if ctx is None:
if target_label:
raise SyntaxError(f"label '{target_label}' not found")
else:
raise SyntaxError("'break' outside of loop")The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
557→ self._patch_jump(pos, loop_start)
558→
559→ self.loop_stack.pop()
560→
561→ elif isinstance(node, BreakStatement):
562→ if not self.loop_stack:
563→ raise SyntaxError("'break' outside of loop")
564→
565→ # Find the right loop context (labeled or innermost loop/switch)
566→ target_label = node.label.name if node.label else None
567→ ctx = None
568→ for loop_ctx in reversed(self.loop_stack):
569→ if target_label is not None:
570→ # Labeled break - find the matching label
571→ if loop_ctx.label == target_label:
572→ ctx = loop_ctx
573→ break
574→ else:
575→ # Unlabeled break - find innermost loop or switch
576→ # is_loop=True means it's a loop, is_loop=False with no label means switch
577→ # Skip labeled statements (is_loop=False with label) for unlabeled break
578→ if loop_ctx.is_loop or loop_ctx.label is None:
579→ ctx = loop_ctx
580→ break
581→
582→ if ctx is None:
583→ if target_label:
584→ raise SyntaxError(f"label '{target_label}' not found")
585→ else:
586→ raise SyntaxError("'break' outside of loop")
587→
588→ # Emit pending finally blocks before the break
589→ self._emit_pending_finally_blocks()
590→.. [ 43%] tests/test_parser.py ................................................... [ 56%] ........ [ 58%] tests/test_regex.py .................................................... [ 71%] .................................... [ 80%] tests/test_string_regex.py ................... [ 85%] tests/test_vm.py ....................................................... [ 99%] . [100%] ======================== 385 passed, 5 xfailed in 4.63s ========================
git add -A && git commit -m "$(cat <<'EOF' Fix labeled statement break/continue semantics - LabeledStatement now uses is_loop=False so unlabeled break/continue skip it - Unlabeled break targets innermost loop OR switch (is_loop=True or no label) - Unlabeled break skips labeled statements (is_loop=False with label) - Labeled break still targets the specific label - Fixes 'while (1) label: break;' infinite loop EOF )"
2 files changed, 36 insertions(+), 6 deletions(-)
Now let me move on to the next item: making Object/Array/Function callable as constructors. Let me write a failing test first:
Todos have been modified successfully. Ensure that you continue to use the todo list to track your progress. Please proceed with the current tasks if applicable
class TestLabeledStatements:
"""Test labeled statements."""
def test_labeled_break_after_while(self):
"""Labeled break after while without braces."""
ctx = JSContext()
# Should not hang - breaks immediately
result = ctx.eval("var x = 0; while (1) label: break; x")
assert result == 0
def test_labeled_break_in_block(self):
"""Labeled break in block."""
ctx = JSContext()
result = ctx.eval("var x = 0; label: { x = 1; break label; x = 2; } x")
assert result == 1class TestLabeledStatements:
"""Test labeled statements."""
def test_labeled_break_after_while(self):
"""Labeled break after while without braces."""
ctx = JSContext()
# Should not hang - breaks immediately
result = ctx.eval("var x = 0; while (1) label: break; x")
assert result == 0
def test_labeled_break_in_block(self):
"""Labeled break in block."""
ctx = JSContext()
result = ctx.eval("var x = 0; label: { x = 1; break label; x = 2; } x")
assert result == 1
class TestBuiltinConstructors:
"""Test built-in constructors like new Object(), new Array()."""
def test_new_object(self):
"""new Object() creates empty object."""
ctx = JSContext()
result = ctx.eval("var o = new Object(); o.x = 1; o.x")
assert result == 1
def test_new_array(self):
"""new Array() creates array."""
ctx = JSContext()
result = ctx.eval("new Array(3).length")
assert result == 3
def test_new_array_with_elements(self):
"""new Array(1, 2, 3) creates array with elements."""
ctx = JSContext()
result = ctx.eval("var a = new Array(1, 2, 3); a[1]")
assert result == 2The file /home/user/mquickjs-python/tests/test_vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
419→ ''')
420→ assert result == "tf"
421→
422→
423→class TestLabeledStatements:
424→ """Test labeled statements."""
425→
426→ def test_labeled_break_after_while(self):
427→ """Labeled break after while without braces."""
428→ ctx = JSContext()
429→ # Should not hang - breaks immediately
430→ result = ctx.eval("var x = 0; while (1) label: break; x")
431→ assert result == 0
432→
433→ def test_labeled_break_in_block(self):
434→ """Labeled break in block."""
435→ ctx = JSContext()
436→ result = ctx.eval("var x = 0; label: { x = 1; break label; x = 2; } x")
437→ assert result == 1
438→
439→
440→class TestBuiltinConstructors:
441→ """Test built-in constructors like new Object(), new Array()."""
442→
443→ def test_new_object(self):
444→ """new Object() creates empty object."""
445→ ctx = JSContext()
446→ result = ctx.eval("var o = new Object(); o.x = 1; o.x")
447→ assert result == 1
448→
449→ def test_new_array(self):
450→ """new Array() creates array."""
451→ ctx = JSContext()
452→ result = ctx.eval("new Array(3).length")
453→ assert result == 3
454→
455→ def test_new_array_with_elements(self):
456→ """new Array(1, 2, 3) creates array with elements."""
457→ ctx = JSContext()
458→ result = ctx.eval("var a = new Array(1, 2, 3); a[1]")
459→ assert result == 2
460→uv run pytest tests/test_vm.py::TestBuiltinConstructors::test_new_object -v 2>&1
Exit code 1
============================= test session starts ==============================
platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python
cachedir: .pytest_cache
rootdir: /home/user/mquickjs-python
configfile: pyproject.toml
collecting ... collected 1 item
tests/test_vm.py::TestBuiltinConstructors::test_new_object FAILED [100%]
=================================== FAILURES ===================================
___________________ TestBuiltinConstructors.test_new_object ____________________
self = <test_vm.TestBuiltinConstructors object at 0x7ea4857f4d50>
def test_new_object(self):
"""new Object() creates empty object."""
ctx = JSContext()
> result = ctx.eval("var o = new Object(); o.x = 1; o.x")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
tests/test_vm.py:446:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
src/mquickjs_python/context.py:603: in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
src/mquickjs_python/vm.py:106: in run
return self._execute()
^^^^^^^^^^^^^^^
src/mquickjs_python/vm.py:163: in _execute
self._execute_opcode(op, arg, frame)
src/mquickjs_python/vm.py:506: in _execute_opcode
self._new_object(arg)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
self = <mquickjs_python.vm.VM object at 0x7ea4857e6d90>, arg_count = 0
def _new_object(self, arg_count: int) -> None:
"""Create a new object with constructor."""
args = []
for _ in range(arg_count):
args.insert(0, self.stack.pop())
constructor = self.stack.pop()
if isinstance(constructor, JSFunction):
# Create new object
obj = JSObject()
# Call constructor with new object as 'this'
self._invoke_js_function(constructor, args, obj)
# Result is the new object (or returned value if object)
self.stack.append(obj)
elif isinstance(constructor, JSObject) and hasattr(constructor, '_callable'):
# Built-in constructor (like RegExp)
result = constructor._callable(*args)
self.stack.append(result)
else:
> raise JSTypeError(f"{constructor} is not a constructor")
E mquickjs_python.errors.JSTypeError: TypeError: JSObject({'keys': <function JSContext._create_object_constructor.<locals>.keys_fn at 0x7ea485a93ba0>, 'values': <function JSContext._create_object_constructor.<locals>.values_fn at 0x7ea485a939c0>, 'entries': <function JSContext._create_object_constructor.<locals>.entries_fn at 0x7ea485a93c40>, 'assign': <function JSContext._create_object_constructor.<locals>.assign_fn at 0x7ea485a93ce0>}) is not a constructor
src/mquickjs_python/vm.py:1629: JSTypeError
=========================== short test summary info ============================
FAILED tests/test_vm.py::TestBuiltinConstructors::test_new_object - mquickjs_...
============================== 1 failed in 0.35s ===============================Good, the test fails as expected. Now I need to make Object work as a constructor. Looking at the code, Object is a JSObject but doesn't have _callable. I need to:1. Make Object a callable object that can be used with new2. The VM checks for JSObject with _callable attribute
Looking at the code, there's JSCallableObject in values.py which is designed for this. Let me look at how Object is created in context.py:
{
"-C": 10,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"pattern": "_create_object_constructor"
}38- console = JSObject()
39- console.set("log", self._console_log)
40- self._globals["console"] = console
41-
42- # Infinity and NaN
43- self._globals["Infinity"] = float("inf")
44- self._globals["NaN"] = float("nan")
45- self._globals["undefined"] = UNDEFINED
46-
47- # Basic type constructors (minimal implementations)
48: self._globals["Object"] = self._create_object_constructor()
49- self._globals["Array"] = self._array_constructor
50- self._globals["Error"] = self._error_constructor
51-
52- # Math object
53- self._globals["Math"] = self._create_math_object()
54-
55- # JSON object
56- self._globals["JSON"] = self._create_json_object()
57-
58- # Number constructor and methods
--
73- # Global number functions
74- self._globals["isNaN"] = self._global_isnan
75- self._globals["isFinite"] = self._global_isfinite
76- self._globals["parseInt"] = self._global_parseint
77- self._globals["parseFloat"] = self._global_parsefloat
78-
79- def _console_log(self, *args: JSValue) -> None:
80- """Console.log implementation."""
81- print(" ".join(to_string(arg) for arg in args))
82-
83: def _create_object_constructor(self) -> JSObject:
84- """Create the Object constructor with static methods."""
85- # Create a callable object that acts as constructor
86- obj_constructor = JSObject()
87-
88- def keys_fn(*args):
89- obj = args[0] if args else UNDEFINED
90- if not isinstance(obj, JSObject):
91- return JSArray()
92- arr = JSArray()
93- arr._elements = list(obj.keys())I need to change JSObject() to JSCallableObject for Object constructor. Let me look at the full implementation and also at how the VM handles constructors:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"limit": 50,
"offset": 83
} 83→ def _create_object_constructor(self) -> JSObject:
84→ """Create the Object constructor with static methods."""
85→ # Create a callable object that acts as constructor
86→ obj_constructor = JSObject()
87→
88→ def keys_fn(*args):
89→ obj = args[0] if args else UNDEFINED
90→ if not isinstance(obj, JSObject):
91→ return JSArray()
92→ arr = JSArray()
93→ arr._elements = list(obj.keys())
94→ return arr
95→
96→ def values_fn(*args):
97→ obj = args[0] if args else UNDEFINED
98→ if not isinstance(obj, JSObject):
99→ return JSArray()
100→ arr = JSArray()
101→ arr._elements = [obj.get(k) for k in obj.keys()]
102→ return arr
103→
104→ def entries_fn(*args):
105→ obj = args[0] if args else UNDEFINED
106→ if not isinstance(obj, JSObject):
107→ return JSArray()
108→ arr = JSArray()
109→ arr._elements = []
110→ for k in obj.keys():
111→ entry = JSArray()
112→ entry._elements = [k, obj.get(k)]
113→ arr._elements.append(entry)
114→ return arr
115→
116→ def assign_fn(*args):
117→ if not args:
118→ return JSObject()
119→ target = args[0]
120→ if not isinstance(target, JSObject):
121→ return target
122→ for i in range(1, len(args)):
123→ source = args[i]
124→ if isinstance(source, JSObject):
125→ for k in source.keys():
126→ target.set(k, source.get(k))
127→ return target
128→
129→ obj_constructor.set("keys", keys_fn)
130→ obj_constructor.set("values", values_fn)
131→ obj_constructor.set("entries", entries_fn)
132→ obj_constructor.set("assign", assign_fn)
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 40,
"offset": 1610
} 1610→ def _new_object(self, arg_count: int) -> None:
1611→ """Create a new object with constructor."""
1612→ args = []
1613→ for _ in range(arg_count):
1614→ args.insert(0, self.stack.pop())
1615→ constructor = self.stack.pop()
1616→
1617→ if isinstance(constructor, JSFunction):
1618→ # Create new object
1619→ obj = JSObject()
1620→ # Call constructor with new object as 'this'
1621→ self._invoke_js_function(constructor, args, obj)
1622→ # Result is the new object (or returned value if object)
1623→ self.stack.append(obj)
1624→ elif isinstance(constructor, JSObject) and hasattr(constructor, '_callable'):
1625→ # Built-in constructor (like RegExp)
1626→ result = constructor._callable(*args)
1627→ self.stack.append(result)
1628→ else:
1629→ raise JSTypeError(f"{constructor} is not a constructor")
1630→
1631→ def _throw(self, exc: JSValue) -> None:
1632→ """Throw an exception."""
1633→ if self.exception_handlers:
1634→ frame_idx, catch_ip = self.exception_handlers.pop()
1635→
1636→ # Unwind call stack
1637→ while len(self.call_stack) > frame_idx + 1:
1638→ self.call_stack.pop()
1639→
1640→ # Jump to catch handler
1641→ frame = self.call_stack[-1]
1642→ frame.ip = catch_ip
1643→
1644→ # Push exception value
1645→ self.stack.append(exc)
1646→ else:
1647→ # Uncaught exception
1648→ if isinstance(exc, str):
1649→ raise JSError(exc)
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see. The VM checks for hasattr(constructor, '_callable'). I should use JSCallableObject which has a callable interface. Let me look at values.py to understand JSCallableObject:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/values.py",
"limit": 20,
"offset": 238
} 238→
239→class JSCallableObject(JSObject):
240→ """JavaScript object that is also callable (for constructors like Number, String, Boolean)."""
241→
242→ def __init__(self, call_fn, prototype: Optional["JSObject"] = None):
243→ super().__init__(prototype)
244→ self._call_fn = call_fn
245→
246→ def __call__(self, *args):
247→ return self._call_fn(*args)
248→
249→ def __repr__(self) -> str:
250→ return f"JSCallableObject({self._properties})"
251→
252→
253→class JSArray(JSObject):
254→ """JavaScript array."""
255→
256→ def __init__(self, length: int = 0):
257→ super().__init__()
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see. The VM checks for _callable attribute. JSCallableObject has _call_fn not _callable. Let me fix the VM to check for _call_fn or make the Object constructor use the right approach.
Actually, looking at the VM code again:
elif isinstance(constructor, JSObject) and hasattr(constructor, '_callable'):
# Built-in constructor (like RegExp)
result = constructor._callable(*args)
It checks for _callable attribute. But JSCallableObject uses _call_fn. I need to either:
1. Change JSCallableObject to use _callable
2. Or change the VM to check for _call_fn
3. Or add _callable to the Object constructor
Let me use option 1 - use JSCallableObject but change the VM to use _call_fn since that's what JSCallableObject provides:
I need to fix the VM to use _call_fn (which is what JSCallableObject has) and update the Object constructor to use JSCallableObject:
elif isinstance(constructor, JSObject) and hasattr(constructor, '_callable'):
# Built-in constructor (like RegExp)
result = constructor._callable(*args)
self.stack.append(result) elif isinstance(constructor, JSObject) and hasattr(constructor, '_call_fn'):
# Built-in constructor (like Object, Array, RegExp)
result = constructor._call_fn(*args)
self.stack.append(result)<tool_use_error>File has not been read yet. Read it first before writing to it.</tool_use_error>
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 15,
"offset": 1620
} 1620→ # Call constructor with new object as 'this'
1621→ self._invoke_js_function(constructor, args, obj)
1622→ # Result is the new object (or returned value if object)
1623→ self.stack.append(obj)
1624→ elif isinstance(constructor, JSObject) and hasattr(constructor, '_callable'):
1625→ # Built-in constructor (like RegExp)
1626→ result = constructor._callable(*args)
1627→ self.stack.append(result)
1628→ else:
1629→ raise JSTypeError(f"{constructor} is not a constructor")
1630→
1631→ def _throw(self, exc: JSValue) -> None:
1632→ """Throw an exception."""
1633→ if self.exception_handlers:
1634→ frame_idx, catch_ip = self.exception_handlers.pop()
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
elif isinstance(constructor, JSObject) and hasattr(constructor, '_callable'):
# Built-in constructor (like RegExp)
result = constructor._callable(*args)
self.stack.append(result) elif isinstance(constructor, JSObject) and hasattr(constructor, '_call_fn'):
# Built-in constructor (like Object, Array, RegExp)
result = constructor._call_fn(*args)
self.stack.append(result)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
1620→ # Call constructor with new object as 'this'
1621→ self._invoke_js_function(constructor, args, obj)
1622→ # Result is the new object (or returned value if object)
1623→ self.stack.append(obj)
1624→ elif isinstance(constructor, JSObject) and hasattr(constructor, '_call_fn'):
1625→ # Built-in constructor (like Object, Array, RegExp)
1626→ result = constructor._call_fn(*args)
1627→ self.stack.append(result)
1628→ else:
1629→ raise JSTypeError(f"{constructor} is not a constructor")
1630→
1631→ def _throw(self, exc: JSValue) -> None:{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"limit": 30,
"offset": 1
} 1→"""JavaScript execution context."""
2→
3→import json
4→import math
5→import random
6→import time
7→from typing import Any, Dict, Optional
8→
9→from .parser import Parser
10→from .compiler import Compiler
11→from .vm import VM
12→from .values import UNDEFINED, NULL, JSValue, JSObject, JSCallableObject, JSArray, JSRegExp, to_string, to_number
13→from .errors import JSError, MemoryLimitError, TimeLimitError
14→
15→
16→class JSContext:
17→ """JavaScript execution context with configurable limits."""
18→
19→ def __init__(
20→ self,
21→ memory_limit: Optional[int] = None,
22→ time_limit: Optional[float] = None,
23→ ):
24→ """Create a new JavaScript context.
25→
26→ Args:
27→ memory_limit: Maximum memory usage in bytes (approximate)
28→ time_limit: Maximum execution time in seconds
29→ """
30→ self.memory_limit = memory_limit
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
Good, JSCallableObject is already imported. Now let me update the _create_object_constructor function to use it:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"limit": 60,
"offset": 83
} 83→ def _create_object_constructor(self) -> JSObject:
84→ """Create the Object constructor with static methods."""
85→ # Create a callable object that acts as constructor
86→ obj_constructor = JSObject()
87→
88→ def keys_fn(*args):
89→ obj = args[0] if args else UNDEFINED
90→ if not isinstance(obj, JSObject):
91→ return JSArray()
92→ arr = JSArray()
93→ arr._elements = list(obj.keys())
94→ return arr
95→
96→ def values_fn(*args):
97→ obj = args[0] if args else UNDEFINED
98→ if not isinstance(obj, JSObject):
99→ return JSArray()
100→ arr = JSArray()
101→ arr._elements = [obj.get(k) for k in obj.keys()]
102→ return arr
103→
104→ def entries_fn(*args):
105→ obj = args[0] if args else UNDEFINED
106→ if not isinstance(obj, JSObject):
107→ return JSArray()
108→ arr = JSArray()
109→ arr._elements = []
110→ for k in obj.keys():
111→ entry = JSArray()
112→ entry._elements = [k, obj.get(k)]
113→ arr._elements.append(entry)
114→ return arr
115→
116→ def assign_fn(*args):
117→ if not args:
118→ return JSObject()
119→ target = args[0]
120→ if not isinstance(target, JSObject):
121→ return target
122→ for i in range(1, len(args)):
123→ source = args[i]
124→ if isinstance(source, JSObject):
125→ for k in source.keys():
126→ target.set(k, source.get(k))
127→ return target
128→
129→ obj_constructor.set("keys", keys_fn)
130→ obj_constructor.set("values", values_fn)
131→ obj_constructor.set("entries", entries_fn)
132→ obj_constructor.set("assign", assign_fn)
133→
134→ return obj_constructor
135→
136→ def _array_constructor(self, *args: JSValue) -> JSArray:
137→ """Array constructor."""
138→ if len(args) == 1 and isinstance(args[0], (int, float)):
139→ return JSArray(int(args[0]))
140→ arr = JSArray()
141→ for arg in args:
142→ arr.push(arg)
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
def _create_object_constructor(self) -> JSObject:
"""Create the Object constructor with static methods."""
# Create a callable object that acts as constructor
obj_constructor = JSObject()
def keys_fn(*args): def _create_object_constructor(self) -> JSCallableObject:
"""Create the Object constructor with static methods."""
# Constructor function - new Object() creates empty object
def object_constructor(*args):
return JSObject()
# Create a callable object that acts as constructor
obj_constructor = JSCallableObject(object_constructor)
def keys_fn(*args):The file /home/user/mquickjs-python/src/mquickjs_python/context.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
79→ def _console_log(self, *args: JSValue) -> None:
80→ """Console.log implementation."""
81→ print(" ".join(to_string(arg) for arg in args))
82→
83→ def _create_object_constructor(self) -> JSCallableObject:
84→ """Create the Object constructor with static methods."""
85→ # Constructor function - new Object() creates empty object
86→ def object_constructor(*args):
87→ return JSObject()
88→
89→ # Create a callable object that acts as constructor
90→ obj_constructor = JSCallableObject(object_constructor)
91→
92→ def keys_fn(*args):
93→ obj = args[0] if args else UNDEFINED
94→ if not isinstance(obj, JSObject):
95→ return JSArray()
96→ arr = JSArray()This session is being continued from a previous conversation that ran out of context. The conversation is summarized below: Analysis: Let me analyze the conversation chronologically:
Regex lookbehind assertions
User Request: "Finish it, TDD, commit often" - The user wants me to implement all remaining features using Test-Driven Development and commit frequently.
Todo List Created: I analyzed the remaining xfail tests and created a comprehensive todo list:
microbench.js - needs many advanced features
Work Done: a. Fixed labeled statement break/continue semantics:
while (1) label: break; caused infinite loopb. Started making Object/Array constructors work:
- Issue: new Object() throws "is not a constructor"
- Root cause: VM checks for _callable attribute but JSCallableObject uses _call_fn
- Fix in progress: Changed VM to check for _call_fn, updated Object constructor to use JSCallableObject
"Finish it, TDD, commit often" - The main directive
Current Work: I was in the middle of implementing new Object() support by:
_call_fn instead of _callableSummary: 1. Primary Request and Intent: The user wants me to implement all remaining features needed to pass the xfail JavaScript tests from the original mquickjs C implementation. The approach should be TDD (Test-Driven Development) - write a failing test first, then implement the fix, then commit. The user emphasized committing often.
Distinction between loops, switch statements, and labeled statements for break targeting
Files and Code Sections:
src/mquickjs_python/compiler.py:
python
elif isinstance(node, LabeledStatement):
# Create a loop context for the label
# is_loop=False so unlabeled break/continue skip this context
loop_ctx = LoopContext(label=node.label.name, is_loop=False)
self.loop_stack.append(loop_ctx)python
else:
# Unlabeled break - find innermost loop or switch
# is_loop=True means it's a loop, is_loop=False with no label means switch
# Skip labeled statements (is_loop=False with label) for unlabeled break
if loop_ctx.is_loop or loop_ctx.label is None:
ctx = loop_ctx
breaksrc/mquickjs_python/vm.py:
_call_fn instead of _callable:
python
elif isinstance(constructor, JSObject) and hasattr(constructor, '_call_fn'):
# Built-in constructor (like Object, Array, RegExp)
result = constructor._call_fn(*args)
self.stack.append(result)src/mquickjs_python/context.py:
Updated _create_object_constructor to use JSCallableObject: ```python def _create_object_constructor(self) -> JSCallableObject: """Create the Object constructor with static methods.""" # Constructor function - new Object() creates empty object def object_constructor(*args): return JSObject()
# Create a callable object that acts as constructor obj_constructor = JSCallableObject(object_constructor) ```
tests/test_vm.py:
tests/test_js_basic.py:
Errors and fixes:
while (1) label: break; hung foreverloop_ctx.is_loop or loop_ctx.label is None for unlabeled breaknew Object() not a constructor: VM couldn't construct Object
_call_fn, updated Object constructor to use JSCallableObjectProblem Solving:
Currently solving built-in constructor support
All user messages:
"Finish it, TDD, commit often"
Pending Tasks (from todo list):
Add bitwise operators
Current Work:
I was implementing new Object() support. I had:
python
class TestBuiltinConstructors:
def test_new_object(self):
ctx = JSContext()
result = ctx.eval("var o = new Object(); o.x = 1; o.x")
assert result == 1_call_fn in _new_object methodJust updated _create_object_constructor to use JSCallableObject with a constructor function
Optional Next Step:
Run the test to verify new Object() now works:
uv run pytest tests/test_vm.py::TestBuiltinConstructors -v
Then if it passes, commit and move on to new Array() which also needs similar treatment.
User's directive: "Finish it, TDD, commit often" - Continue implementing the remaining features from the todo list.. Please continue the conversation from where we left it off without asking the user any further questions. Continue with the last task that you were asked to work on.
The user wants me to continue from where we left off. Looking at the summary, I was in the middle of implementing new Object() support. I had:
new Object() and new Array()_call_fn in _new_object methodThe next step is to run the tests to verify the changes work, then commit and continue with the remaining tasks.
Let me first check the current state by running the tests.
I'll continue implementing the built-in constructors. Let me first run the tests to see the current state after the changes I made.
uv run pytest tests/test_vm.py::TestBuiltinConstructors -v 2>&1 | head -50
============================= test session starts ==============================
platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python
cachedir: .pytest_cache
rootdir: /home/user/mquickjs-python
configfile: pyproject.toml
collecting ... collected 3 items
tests/test_vm.py::TestBuiltinConstructors::test_new_object PASSED [ 33%]
tests/test_vm.py::TestBuiltinConstructors::test_new_array FAILED [ 66%]
tests/test_vm.py::TestBuiltinConstructors::test_new_array_with_elements FAILED [100%]
=================================== FAILURES ===================================
____________________ TestBuiltinConstructors.test_new_array ____________________
self = <test_vm.TestBuiltinConstructors object at 0x7ece6d856b50>
def test_new_array(self):
"""new Array() creates array."""
ctx = JSContext()
> result = ctx.eval("new Array(3).length")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
tests/test_vm.py:452:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
src/mquickjs_python/context.py:607: in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
src/mquickjs_python/vm.py:106: in run
return self._execute()
^^^^^^^^^^^^^^^
src/mquickjs_python/vm.py:163: in _execute
self._execute_opcode(op, arg, frame)
src/mquickjs_python/vm.py:506: in _execute_opcode
self._new_object(arg)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
self = <mquickjs_python.vm.VM object at 0x7ece6d8da610>, arg_count = 1
def _new_object(self, arg_count: int) -> None:
"""Create a new object with constructor."""
args = []
for _ in range(arg_count):
args.insert(0, self.stack.pop())
constructor = self.stack.pop()
if isinstance(constructor, JSFunction):
# Create new object
obj = JSObject()
# Call constructor with new object as 'this'
self._invoke_js_function(constructor, args, obj)Good progress! new Object() is passing. Now I need to fix new Array(). The issue is that Array constructor also needs to use JSCallableObject. Let me read the current context.py to see how Array is set up.
new Object() is passing. Now I need to fix new Array(). Let me check the current Array constructor setup:
{
"output_mode": "files_with_matches",
"path": "/home/user/mquickjs-python/src/mquickjs_python",
"pattern": "_create_array_constructor"
}There might not be an Array constructor yet, or it might be set up differently. Let me search for how Array is defined in the context.
{
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python",
"pattern": "globals\\[.Array"
}{
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"pattern": "_array_constructor"
}49: self._globals["Array"] = self._array_constructor 140: def _array_constructor(self, *args: JSValue) -> JSArray:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"limit": 30,
"offset": 140
} 140→ def _array_constructor(self, *args: JSValue) -> JSArray:
141→ """Array constructor."""
142→ if len(args) == 1 and isinstance(args[0], (int, float)):
143→ return JSArray(int(args[0]))
144→ arr = JSArray()
145→ for arg in args:
146→ arr.push(arg)
147→ return arr
148→
149→ def _error_constructor(self, message: JSValue = UNDEFINED) -> JSObject:
150→ """Error constructor."""
151→ err = JSObject()
152→ err.set("message", to_string(message) if message is not UNDEFINED else "")
153→ err.set("name", "Error")
154→ return err
155→
156→ def _create_math_object(self) -> JSObject:
157→ """Create the Math global object."""
158→ math_obj = JSObject()
159→
160→ # Constants
161→ math_obj.set("PI", math.pi)
162→ math_obj.set("E", math.e)
163→ math_obj.set("LN2", math.log(2))
164→ math_obj.set("LN10", math.log(10))
165→ math_obj.set("LOG2E", 1 / math.log(2))
166→ math_obj.set("LOG10E", 1 / math.log(10))
167→ math_obj.set("SQRT2", math.sqrt(2))
168→ math_obj.set("SQRT1_2", math.sqrt(0.5))
169→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see - the Array constructor is a plain Python method, not a JSCallableObject. I need to wrap it in a JSCallableObject similar to what was done for Object. Let me check how Object constructor is set up now.
I see the issue - Array is a plain method, not wrapped in a JSCallableObject. Let me check how Object is set up now:
{
"-A": 40,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"pattern": "_create_object_constructor"
}48: self._globals["Object"] = self._create_object_constructor()
49- self._globals["Array"] = self._array_constructor
50- self._globals["Error"] = self._error_constructor
51-
52- # Math object
53- self._globals["Math"] = self._create_math_object()
54-
55- # JSON object
56- self._globals["JSON"] = self._create_json_object()
57-
58- # Number constructor and methods
59- self._globals["Number"] = self._create_number_constructor()
60-
61- # String constructor and methods
62- self._globals["String"] = self._create_string_constructor()
63-
64- # Boolean constructor
65- self._globals["Boolean"] = self._create_boolean_constructor()
66-
67- # Date constructor
68- self._globals["Date"] = self._create_date_constructor()
69-
70- # RegExp constructor
71- self._globals["RegExp"] = self._create_regexp_constructor()
72-
73- # Global number functions
74- self._globals["isNaN"] = self._global_isnan
75- self._globals["isFinite"] = self._global_isfinite
76- self._globals["parseInt"] = self._global_parseint
77- self._globals["parseFloat"] = self._global_parsefloat
78-
79- def _console_log(self, *args: JSValue) -> None:
80- """Console.log implementation."""
81- print(" ".join(to_string(arg) for arg in args))
82-
83: def _create_object_constructor(self) -> JSCallableObject:
84- """Create the Object constructor with static methods."""
85- # Constructor function - new Object() creates empty object
86- def object_constructor(*args):
87- return JSObject()
88-
89- # Create a callable object that acts as constructor
90- obj_constructor = JSCallableObject(object_constructor)
91-
92- def keys_fn(*args):
93- obj = args[0] if args else UNDEFINED
94- if not isinstance(obj, JSObject):
95- return JSArray()
96- arr = JSArray()
97- arr._elements = list(obj.keys())
98- return arr
99-
100- def values_fn(*args):
101- obj = args[0] if args else UNDEFINED
102- if not isinstance(obj, JSObject):
103- return JSArray()
104- arr = JSArray()
105- arr._elements = [obj.get(k) for k in obj.keys()]
106- return arr
107-
108- def entries_fn(*args):
109- obj = args[0] if args else UNDEFINED
110- if not isinstance(obj, JSObject):
111- return JSArray()
112- arr = JSArray()
113- arr._elements = []
114- for k in obj.keys():
115- entry = JSArray()
116- entry._elements = [k, obj.get(k)]
117- arr._elements.append(entry)
118- return arr
119-
120- def assign_fn(*args):
121- if not args:
122- return JSObject()
123- target = args[0]Now I understand the pattern. I need to create a _create_array_constructor method similar to _create_object_constructor that wraps the array constructor in a JSCallableObject. Let me also see what Array methods are needed.
First, let me create the Array constructor properly. I'll also need to add static methods like Array.isArray().
Now I need to create a similar _create_array_constructor method. Let me read where _array_constructor is and refactor it:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"limit": 10,
"offset": 48
} 48→ self._globals["Object"] = self._create_object_constructor()
49→ self._globals["Array"] = self._array_constructor
50→ self._globals["Error"] = self._error_constructor
51→
52→ # Math object
53→ self._globals["Math"] = self._create_math_object()
54→
55→ # JSON object
56→ self._globals["JSON"] = self._create_json_object()
57→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I need to:
1. Create a _create_array_constructor method that returns a JSCallableObject
2. Update line 49 to call this new method
Let me first check what imports are at the top to make sure JSArray is available.
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"limit": 20,
"offset": 1
} 1→"""JavaScript execution context."""
2→
3→import json
4→import math
5→import random
6→import time
7→from typing import Any, Dict, Optional
8→
9→from .parser import Parser
10→from .compiler import Compiler
11→from .vm import VM
12→from .values import UNDEFINED, NULL, JSValue, JSObject, JSCallableObject, JSArray, JSRegExp, to_string, to_number
13→from .errors import JSError, MemoryLimitError, TimeLimitError
14→
15→
16→class JSContext:
17→ """JavaScript execution context with configurable limits."""
18→
19→ def __init__(
20→ self,
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
Let me now create the _create_array_constructor method. First, I need to see where _array_constructor is currently defined so I can replace it.
Let me create the _create_array_constructor method similar to Object. First, I'll update line 49:
self._globals["Array"] = self._array_constructor
self._globals["Array"] = self._create_array_constructor()
The file /home/user/mquickjs-python/src/mquickjs_python/context.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
45→ self._globals["undefined"] = UNDEFINED
46→
47→ # Basic type constructors (minimal implementations)
48→ self._globals["Object"] = self._create_object_constructor()
49→ self._globals["Array"] = self._create_array_constructor()
50→ self._globals["Error"] = self._error_constructor
51→
52→ # Math object
53→ self._globals["Math"] = self._create_math_object()Now I need to replace the existing _array_constructor method with a new _create_array_constructor method that returns a JSCallableObject.
def _array_constructor(self, *args: JSValue) -> JSArray:
"""Array constructor."""
if len(args) == 1 and isinstance(args[0], (int, float)):
return JSArray(int(args[0]))
arr = JSArray()
for arg in args:
arr.push(arg)
return arr def _create_array_constructor(self) -> JSCallableObject:
"""Create the Array constructor with static methods."""
def array_constructor(*args):
if len(args) == 1 and isinstance(args[0], (int, float)):
return JSArray(int(args[0]))
arr = JSArray()
for arg in args:
arr.push(arg)
return arr
arr_constructor = JSCallableObject(array_constructor)
# Array.isArray()
def is_array(*args):
obj = args[0] if args else UNDEFINED
return isinstance(obj, JSArray)
arr_constructor.set("isArray", is_array)
return arr_constructorThe file /home/user/mquickjs-python/src/mquickjs_python/context.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
136→ obj_constructor.set("assign", assign_fn)
137→
138→ return obj_constructor
139→
140→ def _create_array_constructor(self) -> JSCallableObject:
141→ """Create the Array constructor with static methods."""
142→ def array_constructor(*args):
143→ if len(args) == 1 and isinstance(args[0], (int, float)):
144→ return JSArray(int(args[0]))
145→ arr = JSArray()
146→ for arg in args:
147→ arr.push(arg)
148→ return arr
149→
150→ arr_constructor = JSCallableObject(array_constructor)
151→
152→ # Array.isArray()
153→ def is_array(*args):
154→ obj = args[0] if args else UNDEFINED
155→ return isinstance(obj, JSArray)
156→
157→ arr_constructor.set("isArray", is_array)
158→
159→ return arr_constructor
160→
161→ def _error_constructor(self, message: JSValue = UNDEFINED) -> JSObject:
162→ """Error constructor."""
163→ err = JSObject()uv run pytest tests/test_vm.py::TestBuiltinConstructors -v 2>&1 | head -50
============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python cachedir: .pytest_cache rootdir: /home/user/mquickjs-python configfile: pyproject.toml collecting ... collected 3 items tests/test_vm.py::TestBuiltinConstructors::test_new_object PASSED [ 33%] tests/test_vm.py::TestBuiltinConstructors::test_new_array PASSED [ 66%] tests/test_vm.py::TestBuiltinConstructors::test_new_array_with_elements PASSED [100%] ============================== 3 passed in 0.07s ===============================
All constructor tests pass. Let me also run all the tests to make sure I haven't broken anything, then commit this progress.
All constructor tests pass. Let me run the full test suite to make sure nothing is broken:
raise JSTypeError(f"{constructor} is not a constructor")
E mquickjs_python.errors.JSTypeError: TypeError: JSObject({}) is not a constructor
___________________ TestRegExpPatterns.test_character_class ____________________
tests/test_jscontext_regexp.py:161: in test_character_class
result = ctx.eval('new RegExp("[a-z]+").test("hello")')
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/context.py:619: in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
src/mquickjs_python/vm.py:106: in run
return self._execute()
^^^^^^^^^^^^^^^
src/mquickjs_python/vm.py:163: in _execute
self._execute_opcode(op, arg, frame)
src/mquickjs_python/vm.py:506: in _execute_opcode
self._new_object(arg)
src/mquickjs_python/vm.py:1629: in _new_object
raise JSTypeError(f"{constructor} is not a constructor")
E mquickjs_python.errors.JSTypeError: TypeError: JSObject({}) is not a constructor
=========================== short test summary info ============================
FAILED tests/test_js_basic.py::test_basic_js[test_regexp.js-path15] - mquickj...
FAILED tests/test_jscontext_regexp.py::TestRegExpConstructor::test_new_regexp_basic
FAILED tests/test_jscontext_regexp.py::TestRegExpConstructor::test_new_regexp_flags
FAILED tests/test_jscontext_regexp.py::TestRegExpConstructor::test_regexp_global_flag
FAILED tests/test_jscontext_regexp.py::TestRegExpConstructor::test_regexp_ignorecase_flag
FAILED tests/test_jscontext_regexp.py::TestRegExpTest::test_simple_match - mq...
FAILED tests/test_jscontext_regexp.py::TestRegExpTest::test_no_match - mquick...
FAILED tests/test_jscontext_regexp.py::TestRegExpTest::test_case_insensitive_match
FAILED tests/test_jscontext_regexp.py::TestRegExpTest::test_digit_pattern - m...
FAILED tests/test_jscontext_regexp.py::TestRegExpExec::test_exec_match - mqui...
FAILED tests/test_jscontext_regexp.py::TestRegExpExec::test_exec_group - mqui...
FAILED tests/test_jscontext_regexp.py::TestRegExpExec::test_exec_no_match - m...
FAILED tests/test_jscontext_regexp.py::TestRegExpExec::test_exec_index - mqui...
FAILED tests/test_jscontext_regexp.py::TestRegExpGlobal::test_global_exec_advances
FAILED tests/test_jscontext_regexp.py::TestRegExpGlobal::test_lastindex_property
FAILED tests/test_jscontext_regexp.py::TestRegExpPatterns::test_word_boundary
FAILED tests/test_jscontext_regexp.py::TestRegExpPatterns::test_anchors - mqu...
FAILED tests/test_jscontext_regexp.py::TestRegExpPatterns::test_quantifiers
FAILED tests/test_jscontext_regexp.py::TestRegExpPatterns::test_character_class
================== 19 failed, 369 passed, 5 xfailed in 6.23s ===================I see - the RegExp constructor also needs to be wrapped in JSCallableObject. Let me check how it's currently defined and fix it.
{
"-A": 30,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"pattern": "_create_regexp_constructor"
}71: self._globals["RegExp"] = self._create_regexp_constructor()
72-
73- # Global number functions
74- self._globals["isNaN"] = self._global_isnan
75- self._globals["isFinite"] = self._global_isfinite
76- self._globals["parseInt"] = self._global_parseint
77- self._globals["parseFloat"] = self._global_parsefloat
78-
79- def _console_log(self, *args: JSValue) -> None:
80- """Console.log implementation."""
81- print(" ".join(to_string(arg) for arg in args))
82-
83- def _create_object_constructor(self) -> JSCallableObject:
84- """Create the Object constructor with static methods."""
85- # Constructor function - new Object() creates empty object
86- def object_constructor(*args):
87- return JSObject()
88-
89- # Create a callable object that acts as constructor
90- obj_constructor = JSCallableObject(object_constructor)
91-
92- def keys_fn(*args):
93- obj = args[0] if args else UNDEFINED
94- if not isinstance(obj, JSObject):
95- return JSArray()
96- arr = JSArray()
97- arr._elements = list(obj.keys())
98- return arr
99-
100- def values_fn(*args):
101- obj = args[0] if args else UNDEFINED
--
499: def _create_regexp_constructor(self) -> JSObject:
500- """Create the RegExp constructor."""
501- # The constructor is a callable that creates JSRegExp objects
502- # This is wrapped in JSObject but the VM will call it specially
503-
504- def regexp_constructor_fn(*args):
505- pattern = to_string(args[0]) if args else ""
506- flags = to_string(args[1]) if len(args) > 1 else ""
507- return JSRegExp(pattern, flags)
508-
509- # Return a callable marker
510- regexp_constructor = JSObject()
511- regexp_constructor._callable = regexp_constructor_fn
512- return regexp_constructor
513-
514- def _global_isnan(self, *args) -> bool:
515- """Global isNaN - converts argument to number first."""
516- x = to_number(args[0]) if args else float('nan')
517- return math.isnan(x)
518-
519- def _global_isfinite(self, *args) -> bool:
520- """Global isFinite - converts argument to number first."""
521- x = to_number(args[0]) if args else float('nan')
522- return not (math.isnan(x) or math.isinf(x))
523-
524- def _global_parseint(self, *args):
525- """Global parseInt."""
526- s = to_string(args[0]) if args else ""
527- radix = int(to_number(args[1])) if len(args) > 1 else 10
528- if radix == 0:
529- radix = 10I see the issue - RegExp uses a different pattern with _callable attribute. The VM change I made now checks for _call_fn which is used by JSCallableObject. I need to update the RegExp constructor to use JSCallableObject as well.
I see the issue - RegExp uses _callable but the VM now checks for _call_fn. Let me update the RegExp constructor to use JSCallableObject:
def _create_regexp_constructor(self) -> JSObject:
"""Create the RegExp constructor."""
# The constructor is a callable that creates JSRegExp objects
# This is wrapped in JSObject but the VM will call it specially
def regexp_constructor_fn(*args):
pattern = to_string(args[0]) if args else ""
flags = to_string(args[1]) if len(args) > 1 else ""
return JSRegExp(pattern, flags)
# Return a callable marker
regexp_constructor = JSObject()
regexp_constructor._callable = regexp_constructor_fn
return regexp_constructor def _create_regexp_constructor(self) -> JSCallableObject:
"""Create the RegExp constructor."""
def regexp_constructor_fn(*args):
pattern = to_string(args[0]) if args else ""
flags = to_string(args[1]) if len(args) > 1 else ""
return JSRegExp(pattern, flags)
return JSCallableObject(regexp_constructor_fn)The file /home/user/mquickjs-python/src/mquickjs_python/context.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
495→ date_constructor.set("now", now_fn)
496→
497→ return date_constructor
498→
499→ def _create_regexp_constructor(self) -> JSCallableObject:
500→ """Create the RegExp constructor."""
501→ def regexp_constructor_fn(*args):
502→ pattern = to_string(args[0]) if args else ""
503→ flags = to_string(args[1]) if len(args) > 1 else ""
504→ return JSRegExp(pattern, flags)
505→
506→ return JSCallableObject(regexp_constructor_fn)
507→
508→ def _global_isnan(self, *args) -> bool:
509→ """Global isNaN - converts argument to number first."""
510→ x = to_number(args[0]) if args else float('nan')Now I need to check if there are any other places using _callable. Let me also check Error constructor.
{
"-A": 10,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"pattern": "_error_constructor"
}50: self._globals["Error"] = self._error_constructor
51-
52- # Math object
53- self._globals["Math"] = self._create_math_object()
54-
55- # JSON object
56- self._globals["JSON"] = self._create_json_object()
57-
58- # Number constructor and methods
59- self._globals["Number"] = self._create_number_constructor()
60-
--
161: def _error_constructor(self, message: JSValue = UNDEFINED) -> JSObject:
162- """Error constructor."""
163- err = JSObject()
164- err.set("message", to_string(message) if message is not UNDEFINED else "")
165- err.set("name", "Error")
166- return err
167-
168- def _create_math_object(self) -> JSObject:
169- """Create the Math global object."""
170- math_obj = JSObject()
171-I see - Error is also using a plain method. Let me run the tests first to see if the RegExp fix is enough, and also check which constructors are being tested.
uv run pytest tests/test_jscontext_regexp.py -v --tb=short 2>&1 | tail -30
============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python cachedir: .pytest_cache rootdir: /home/user/mquickjs-python configfile: pyproject.toml collecting ... collected 18 items tests/test_jscontext_regexp.py::TestRegExpConstructor::test_new_regexp_basic PASSED [ 5%] tests/test_jscontext_regexp.py::TestRegExpConstructor::test_new_regexp_flags PASSED [ 11%] tests/test_jscontext_regexp.py::TestRegExpConstructor::test_regexp_global_flag PASSED [ 16%] tests/test_jscontext_regexp.py::TestRegExpConstructor::test_regexp_ignorecase_flag PASSED [ 22%] tests/test_jscontext_regexp.py::TestRegExpTest::test_simple_match PASSED [ 27%] tests/test_jscontext_regexp.py::TestRegExpTest::test_no_match PASSED [ 33%] tests/test_jscontext_regexp.py::TestRegExpTest::test_case_insensitive_match PASSED [ 38%] tests/test_jscontext_regexp.py::TestRegExpTest::test_digit_pattern PASSED [ 44%] tests/test_jscontext_regexp.py::TestRegExpExec::test_exec_match PASSED [ 50%] tests/test_jscontext_regexp.py::TestRegExpExec::test_exec_group PASSED [ 55%] tests/test_jscontext_regexp.py::TestRegExpExec::test_exec_no_match PASSED [ 61%] tests/test_jscontext_regexp.py::TestRegExpExec::test_exec_index PASSED [ 66%] tests/test_jscontext_regexp.py::TestRegExpGlobal::test_global_exec_advances PASSED [ 72%] tests/test_jscontext_regexp.py::TestRegExpGlobal::test_lastindex_property PASSED [ 77%] tests/test_jscontext_regexp.py::TestRegExpPatterns::test_word_boundary PASSED [ 83%] tests/test_jscontext_regexp.py::TestRegExpPatterns::test_anchors PASSED [ 88%] tests/test_jscontext_regexp.py::TestRegExpPatterns::test_quantifiers PASSED [ 94%] tests/test_jscontext_regexp.py::TestRegExpPatterns::test_character_class PASSED [100%] ============================== 18 passed in 0.10s ==============================
All RegExp tests pass. Now let me run all the tests to make sure everything is good.
tests/test_vm.py::TestStrings::test_string_concatenation PASSED [ 95%] tests/test_vm.py::TestStrings::test_string_length PASSED [ 95%] tests/test_vm.py::TestGlobalAccess::test_set_global PASSED [ 96%] tests/test_vm.py::TestGlobalAccess::test_get_global PASSED [ 96%] tests/test_vm.py::TestVoidOperator::test_void_returns_undefined PASSED [ 96%] tests/test_vm.py::TestVoidOperator::test_void_expression PASSED [ 96%] tests/test_vm.py::TestVoidOperator::test_void_function_call PASSED [ 97%] tests/test_vm.py::TestForOf::test_for_of_array PASSED [ 97%] tests/test_vm.py::TestForOf::test_for_of_string PASSED [ 97%] tests/test_vm.py::TestGetterSetter::test_getter PASSED [ 97%] tests/test_vm.py::TestGetterSetter::test_setter PASSED [ 98%] tests/test_vm.py::TestGetterSetter::test_getter_setter_combined PASSED [ 98%] tests/test_vm.py::TestTryFinallyBreak::test_break_in_try_finally PASSED [ 98%] tests/test_vm.py::TestLabeledStatements::test_labeled_break_after_while PASSED [ 98%] tests/test_vm.py::TestLabeledStatements::test_labeled_break_in_block PASSED [ 99%] tests/test_vm.py::TestBuiltinConstructors::test_new_object PASSED [ 99%] tests/test_vm.py::TestBuiltinConstructors::test_new_array PASSED [ 99%] tests/test_vm.py::TestBuiltinConstructors::test_new_array_with_elements PASSED [100%] ======================== 388 passed, 5 xfailed in 4.58s ========================
388 tests passing, 5 xfailed. Good. Now let me commit this progress and then continue with the remaining features. Let me first check if test_language.js now passes (after the previous labeled statement fix).
src/mquickjs_python/context.py | 48 +++++++++++++++++++++++++----------------- src/mquickjs_python/vm.py | 6 +++--- tests/test_vm.py | 22 +++++++++++++++++++ 3 files changed, 54 insertions(+), 22 deletions(-)
672fe03 Fix labeled statement break/continue semantics 2c07659 Implement regex lookbehind assertions 27601f3 Organize passing mquickjs tests into tests/compat/ directory f3cd9d9 Move passing test files to tests/basic/ directory 6cf3a86 Fix try-finally interaction with break/continue/return and exceptions
git commit -m "$(cat <<'EOF' Make Object/Array/RegExp callable as constructors Refactored built-in constructors to use JSCallableObject: - Object constructor now returns JSCallableObject with static methods - Array constructor now returns JSCallableObject with Array.isArray() - RegExp constructor updated to use JSCallableObject - VM now checks for _call_fn attribute for built-in constructors EOF )"
3 files changed, 54 insertions(+), 22 deletions(-)
The user wants to see the TODO list. Let me also update the todo list and mark the constructor task as complete, then continue with the next tasks.
Todos have been modified successfully. Ensure that you continue to use the todo list to track your progress. Please proceed with the current tasks if applicable
Now let me check which xfailed tests we have and which ones may pass now. Then I'll work through the remaining features.
Here's my current TODO list:
Completed: 1. ✅ Fix labeled statement parsing (test_language.js) 2. ✅ Make Object/Array/Function callable as constructors (new Object())
Pending: 3. Add Object.getPrototypeOf/setPrototypeOf 4. Add Object.defineProperty with getters/setters 5. Add Object.create 6. Add Function constructor (new Function('a','b','return a+b')) 7. Add TypedArrays (Int32Array, Uint8Array, etc) 8. Add ArrayBuffer 9. Add Date.now() 10. Add more String methods (codePointAt, fromCodePoint) 11. Add more Math methods (fround, imul, min) 12. Add JSON.parse/stringify 13. Add eval() function 14. Add instanceof operator 15. Add exponentiation operator (**) 16. Add bitwise operators (<<, >>, >>>, &, |, ^, ~)
Let me check which xfailed tests we have and see what's failing:
uv run pytest tests/test_js_basic.py -v 2>&1 | grep -E "(XFAIL|PASSED|FAILED)" | head -20
tests/test_js_basic.py::test_basic_js[01_empty.js-path0] PASSED [ 3%] tests/test_js_basic.py::test_basic_js[test_array_methods.js-path1] PASSED [ 7%] tests/test_js_basic.py::test_basic_js[test_for_in2.js-path2] PASSED [ 11%] tests/test_js_basic.py::test_basic_js[test_for_in_array.js-path3] PASSED [ 15%] tests/test_js_basic.py::test_basic_js[test_for_in_simple.js-path4] PASSED [ 19%] tests/test_js_basic.py::test_basic_js[test_json.js-path5] PASSED [ 23%] tests/test_js_basic.py::test_basic_js[test_loop_break.js-path6] PASSED [ 26%] tests/test_js_basic.py::test_basic_js[test_loop_for.js-path7] PASSED [ 30%] tests/test_js_basic.py::test_basic_js[test_loop_switch.js-path8] PASSED [ 34%] tests/test_js_basic.py::test_basic_js[test_loop_switch2.js-path9] PASSED [ 38%] tests/test_js_basic.py::test_basic_js[test_loop_try5.js-path10] PASSED [ 42%] tests/test_js_basic.py::test_basic_js[test_loop_while.js-path11] PASSED [ 46%] tests/test_js_basic.py::test_basic_js[test_math.js-path12] PASSED [ 50%] tests/test_js_basic.py::test_basic_js[test_number_date.js-path13] PASSED [ 53%] tests/test_js_basic.py::test_basic_js[test_object_methods.js-path14] PASSED [ 57%] tests/test_js_basic.py::test_basic_js[test_regexp.js-path15] PASSED [ 61%] tests/test_js_basic.py::test_basic_js[test_string_methods.js-path16] PASSED [ 65%] tests/test_js_basic.py::test_basic_js[test_try_catch.js-path17] PASSED [ 69%] tests/test_js_basic.py::test_basic_js[test_try_catch_simple.js-path18] PASSED [ 73%] tests/test_js_basic.py::test_compat_js[test_closure.js-path0] PASSED [ 76%]
uv run pytest tests/test_js_basic.py -v 2>&1 | grep -E "(xfail|XFAIL)"
tests/test_js_basic.py::test_mquickjs_js[mandelbrot.js-path0] XFAIL [ 84%] tests/test_js_basic.py::test_mquickjs_js[microbench.js-path1] XFAIL [ 88%] tests/test_js_basic.py::test_mquickjs_js[test_builtin.js-path2] XFAIL [ 92%] tests/test_js_basic.py::test_mquickjs_js[test_language.js-path3] XFAIL [ 96%] tests/test_js_basic.py::test_mquickjs_js[test_rect.js-path4] XFAIL (...) [100%] ======================== 21 passed, 5 xfailed in 2.91s =========================
There are 5 xfails: 1. mandelbrot.js - complex mandelbrot test 2. microbench.js - microbenchmarks 3. test_builtin.js - tests for built-in objects 4. test_language.js - tests for language features 5. test_rect.js - tests for C bindings (Rectangle class)
Let me run test_language.js to see if it now passes with the labeled statement fixes.
uv run pytest tests/test_js_basic.py::test_mquickjs_js -k "test_language" -v 2>&1 | tail -30
============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python cachedir: .pytest_cache rootdir: /home/user/mquickjs-python configfile: pyproject.toml collecting ... collected 5 items / 4 deselected / 1 selected tests/test_js_basic.py::test_mquickjs_js[test_language.js-path3] XFAIL [100%] ======================= 4 deselected, 1 xfailed in 0.38s =======================
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval(open('tests/mquickjs_compat/test_language.js').read())
print('SUCCESS')
except Exception as e:
print(f'FAILED: {e}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval(open('tests/test_language.js').read())
print('SUCCESS')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1Interesting - a syntax error with RBRACE. This is likely a parsing issue. Let me figure out what specific test is causing this issue.
{
"file_path": "/home/user/mquickjs-python/tests/test_language.js",
"limit": 40,
"offset": 270
} 270→
271→ a = {x: 1, y: 2, __proto__: { z: 3 }};
272→ assert(a.x, 1);
273→ assert(a.y, 2);
274→ assert(Object.getPrototypeOf(a).z, 3);
275→
276→ /* getter/setter/method */
277→ b = 2;
278→ a = {get x() { return b; }, set x(v) { b = v; }, f(v) { return v + 1 },
279→ set: 10, get: 11 };
280→ assert(a.x, 2);
281→ a.x = 3;
282→ assert(a.x, 3);
283→ assert(a.f(3), 4);
284→ assert(a.set, 10);
285→ assert(a.get, 11);
286→
287→ a = { set() { return 1; }, get() { return 2; }}
288→ assert(a.set(), 1);
289→ assert(a.get(), 2);
290→}
291→
292→function test_prototype()
293→{
294→ function f() { }
295→ assert(f.prototype.constructor, f, "prototype");
296→}
297→
298→function test_arguments()
299→{
300→ function f2() {
301→ assert(arguments.length, 2, "arguments");
302→ assert(arguments[0], 1, "arguments");
303→ assert(arguments[1], 3, "arguments");
304→ }
305→ f2(1, 3);
306→}
307→
308→function test_to_primitive()
309→{
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see line 287 uses set() and get() as method names. This is where set and get are not keywords but method names. This might be confusing the parser.
Let me test just that line:
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('var a = { set() { return 1; }, get() { return 2; }}')
print('SUCCESS')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1That works. Let me try a simpler approach - test the file line by line to find the issue.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
lines = open('tests/test_language.js').readlines()
# Try parsing chunk by chunk
for i in range(0, len(lines), 20):
chunk = ''.join(lines[i:i+20])
try:
# Just try to parse
from mquickjs_python.parser import Parser
p = Parser(chunk)
p.parse()
except Exception as e:
print(f'Error around lines {i+1}-{i+20}: {e}')
# Print problematic lines
for j, line in enumerate(lines[max(0,i):min(len(lines),i+20)], start=max(0,i)+1):
print(f'{j}: {line.rstrip()}')
break
else:
print('All chunks parse fine')
" 2>&1 | head -30Error around lines 1-20: SyntaxError: Expected '}'
1: function throw_error(msg) {
2: throw Error(msg);
3: }
4:
5: function assert(actual, expected, message) {
6: function get_full_type(o) {
7: var type = typeof(o);
8: if (type === 'object') {
9: if (o === null)
10: return 'null';
11: if (o.constructor && o.constructor.name)
12: return o.constructor.name;
13: }
14: return type;
15: }
16:
17: if (arguments.length == 1)
18: expected = true;
19:
20: if (typeof actual === typeof expected) {Hmm, the error is early on. I notice on line 2 there's throw Error(msg). Let me check if throw without parentheses is supported.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('throw Error(\"test\")')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
content = open('tests/test_language.js').read()
# Binary search for error location
start = 0
end = len(content)
while end - start > 100:
mid = (start + end) // 2
# Find a good breaking point (end of statement or line)
break_point = mid
for i in range(mid, min(mid + 50, end)):
if content[i] == '\n':
break_point = i + 1
break
test_content = content[:break_point]
try:
ctx.eval(test_content)
start = break_point
except:
end = break_point
# Found approximate location
print(f'Error near position {start}-{end}')
# Show context
snippet = content[max(0, start-100):min(len(content), end+100)]
print('Context:')
print(snippet)
" 2>&1Error near position 0-98
Context:
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === 'object') {Hmm weird - somehow the file seems to work in chunks but not as a whole. Let me try parsing it differently.
uv run python -c "
from mquickjs_python.parser import Parser
content = open('tests/test_language.js').read()
# Use the parser directly
try:
p = Parser(content)
ast = p.parse()
print('Parse success')
except Exception as e:
print(f'Parse error: {type(e).__name__}: {e}')
import traceback
traceback.print_exc()
" 2>&1 | tail -20 expr = self._parse_binary_expression(0, exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 558, in _parse_binary_expression
left = self._parse_unary_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 657, in _parse_unary_expression
argument = self._parse_unary_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 660, in _parse_unary_expression
return self._parse_postfix_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 664, in _parse_postfix_expression
expr = self._parse_new_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 708, in _parse_new_expression
return self._parse_primary_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 769, in _parse_primary_expression
raise self._error(f"Unexpected token: {self.current.type.name}")
mquickjs_python.errors.JSSyntaxError: SyntaxError: Unexpected token: RBRACEThe error occurs in parsing a primary expression with an RBRACE. This might be related to empty expressions or trailing commas somewhere. Let me add more debugging to see where it fails.
uv run python -c "
from mquickjs_python.parser import Parser
content = open('tests/test_language.js').read()
# Use the parser directly
try:
p = Parser(content)
ast = p.parse()
print('Parse success')
except Exception as e:
print(f'Parse error at line {p.line}, col {p.col}')
# Show what's around that location
lines = content.split('\n')
for i in range(max(0, p.line-3), min(len(lines), p.line+3)):
marker = '>>> ' if i == p.line - 1 else ' '
print(f'{marker}{i+1}: {lines[i]}')
" 2>&1Exit code 1
Traceback (most recent call last):
File "<string>", line 7, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 114, in parse
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 163, in _parse_statement
return self._parse_function_declaration()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 389, in _parse_function_declaration
body = self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 136, in _parse_statement
return self._parse_while_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 221, in _parse_while_statement
body = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 171, in _parse_statement
body = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 127, in _parse_statement
return self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 175, in _parse_statement
return self._parse_expression_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 407, in _parse_expression_statement
expr = self._parse_expression()
^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 419, in _parse_expression
expr = self._parse_assignment_expression(exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 441, in _parse_assignment_expression
expr = self._parse_conditional_expression(exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 546, in _parse_conditional_expression
expr = self._parse_binary_expression(0, exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 558, in _parse_binary_expression
left = self._parse_unary_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 657, in _parse_unary_expression
argument = self._parse_unary_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 660, in _parse_unary_expression
return self._parse_postfix_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 664, in _parse_postfix_expression
expr = self._parse_new_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 708, in _parse_new_expression
return self._parse_primary_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 769, in _parse_primary_expression
raise self._error(f"Unexpected token: {self.current.type.name}")
mquickjs_python.errors.JSSyntaxError: SyntaxError: Unexpected token: RBRACE
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "<string>", line 10, in <module>
AttributeError: 'Parser' object has no attribute 'line'The stack trace shows it's parsing a while statement, then a labeled statement (from line 171), then a block statement, then an expression statement. The issue is in parsing -a inside a while loop with a labeled break.
Looking at the stack trace: 1. function_declaration 2. block_statement 3. while_statement 4. _parse_statement at line 171 (labeled statement) 5. block_statement 6. expression_statement 7. unary expression
The -a should be -a (unary minus) but it seems like it's having trouble after break. Let me look at test_labels2() function:
{
"file_path": "/home/user/mquickjs-python/tests/test_language.js",
"limit": 30,
"offset": 318
} 318→function test_labels()
319→{
320→ do x: { break x; } while(0);
321→ if (1)
322→ x: { break x; }
323→ else
324→ x: { break x; }
325→ while (0) x: { break x; };
326→}
327→
328→function test_labels2()
329→{
330→ while (1) label: break
331→ var i = 0
332→ while (i < 3) label: {
333→ if (i > 0)
334→ break
335→ i++
336→ }
337→ assert(i == 1)
338→ for (;;) label: break
339→ for (i = 0; i < 3; i++) label: {
340→ if (i > 0)
341→ break
342→ }
343→ assert(i == 1)
344→}
345→
346→test_op1();
347→test_cvt();
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see! Line 330: while (1) label: break - there's no block and no semicolon. The parser needs to handle a labeled statement where the body is just a break statement without a block.
Let me test this specific case:
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('while (1) label: break')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
function test_labels2()
{
while (1) label: break
var i = 0
while (i < 3) label: {
if (i > 0)
break
i++
}
for (;;) label: break
for (i = 0; i < 3; i++) label: {
if (i > 0)
break
}
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
function test_labels2()
{
while (1) label: break
var i = 0
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
function test_labels2()
{
while (1) label: break
var i = 0
while (i < 3) label: {
if (i > 0)
break
i++
}
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1Found it! The issue is with while (i < 3) label: { ... }. Let me narrow it down more.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
while (true) label: {
break
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
var i = 0
while (i < 3) label: {
if (i > 0)
break
i++
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1Found it! The issue is with i++ inside the labeled block. Let me simplify further.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
while (true) label: {
var x = 1
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1This is an infinite loop! The while (true) runs forever. Let me kill it and fix the test.
{"message":"Successfully killed shell: 1306aa (uv run python -c \"\nfrom mquickjs_python import JSContext\nctx = JSContext()\ntry:\n ctx.eval('''\nwhile (true) label: {\n var x = 1\n}\n''')\n print('SUCCESS')\nexcept Exception as e:\n print(f'Error: {type(e).__name__}: {e}')\n\" 2>&1)","shell_id":"1306aa"}The code actually ran, so the parsing worked. The issue is that it creates an infinite loop. Let me use false instead.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
while (false) label: {
var x = 1
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
var i = 0
while (false) label: {
i++
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
var i = 0
while (false) label: {
if (i > 0)
break
i++
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1So the issue is related to having both the if statement and the i++. Let me reduce it further.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
while (false) label: {
if (true)
break
1
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1That works! The difference might be ASI (automatic semicolon insertion). Let me try without any semicolons.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
var i = 0
while (false) label: {
if (i > 0)
break
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
{
if (false) break
i++
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1Found it! The issue is i++ after if (false) break. Let me check what break does here.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
{
if (false) x = 1
i++
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1That one only fails at runtime (i is not defined), which is fine. The issue is specific to break. Let me check if break is consuming the next statement.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval('''
{
if (false) break;
i++
}
''')
print('SUCCESS')
except Exception as e:
print(f'Error: {type(e).__name__}: {e}')
" 2>&1Ok, with semicolon it parses fine (error is at compile time about break outside loop). The issue is ASI (automatic semicolon insertion) for break. After break, the parser should insert a semicolon automatically.
Let me check the parser to see how ASI is handled for break.
{
"-A": 20,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/parser.py",
"pattern": "_parse_break_statement"
}145: return self._parse_break_statement() 146- 147- if self._match(TokenType.CONTINUE): 148- return self._parse_continue_statement() 149- 150- if self._match(TokenType.RETURN): 151- return self._parse_return_statement() 152- 153- if self._match(TokenType.THROW): 154- return self._parse_throw_statement() 155- 156- if self._match(TokenType.TRY): 157- return self._parse_try_statement() 158- 159- if self._match(TokenType.SWITCH): 160- return self._parse_switch_statement() 161- 162- if self._match(TokenType.FUNCTION): 163- return self._parse_function_declaration() 164- 165- # Check for labeled statement: IDENTIFIER COLON statement -- 304: def _parse_break_statement(self) -> BreakStatement: 305- """Parse break statement.""" 306- label = None 307- if self._check(TokenType.IDENTIFIER): 308- label = Identifier(self._advance().value) 309- self._consume_semicolon() 310- return BreakStatement(label) 311- 312- def _parse_continue_statement(self) -> ContinueStatement: 313- """Parse continue statement.""" 314- label = None 315- if self._check(TokenType.IDENTIFIER): 316- label = Identifier(self._advance().value) 317- self._consume_semicolon() 318- return ContinueStatement(label) 319- 320- def _parse_return_statement(self) -> ReturnStatement: 321- """Parse return statement.""" 322- argument = None 323- if not self._check(TokenType.SEMICOLON) and not self._check(TokenType.RBRACE): 324- argument = self._parse_expression()
I see - _parse_break_statement parses a break, then optionally looks for an identifier label (if the next token is an IDENTIFIER), then consumes a semicolon.
The issue is that when you have:
if (false) break
i++
The parser sees:
1. break keyword
2. Checks if next token is IDENTIFIER - yes, i is an identifier!
3. So it thinks i is the label for the break statement
4. Then tries to consume semicolon but finds ++
The problem is that i should not be treated as a label if there's no colon after it. But the break statement parser only checks if it's an identifier, not if it's part of a different statement.
In JavaScript, ASI applies after break if the next line doesn't start with a semicolon. The key is that i is on the next line, so ASI should kick in.
Let me check how _consume_semicolon works and how the lexer handles newlines.
{
"-A": 15,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/parser.py",
"pattern": "_consume_semicolon"
}202: self._consume_semicolon()
203- return VariableDeclaration(declarations)
204-
205- def _parse_if_statement(self) -> IfStatement:
206- """Parse if statement: if (test) consequent else alternate"""
207- self._expect(TokenType.LPAREN, "Expected '(' after 'if'")
208- test = self._parse_expression()
209- self._expect(TokenType.RPAREN, "Expected ')' after condition")
210- consequent = self._parse_statement()
211- alternate = None
212- if self._match(TokenType.ELSE):
213- alternate = self._parse_statement()
214- return IfStatement(test, consequent, alternate)
215-
216- def _parse_while_statement(self) -> WhileStatement:
217- """Parse while statement: while (test) body"""
--
231: self._consume_semicolon()
232- return DoWhileStatement(body, test)
233-
234- def _parse_for_statement(self) -> Node:
235- """Parse for/for-in/for-of statement."""
236- self._expect(TokenType.LPAREN, "Expected '(' after 'for'")
237-
238- # Parse init part
239- init = None
240- if self._match(TokenType.SEMICOLON):
241- pass # No init
242- elif self._match(TokenType.VAR):
243- # Could be for or for-in
244- name = self._expect(TokenType.IDENTIFIER, "Expected variable name")
245- if self._match(TokenType.IN):
246- # for (var x in obj)
--
309: self._consume_semicolon()
310- return BreakStatement(label)
311-
312- def _parse_continue_statement(self) -> ContinueStatement:
313- """Parse continue statement."""
314- label = None
315- if self._check(TokenType.IDENTIFIER):
316- label = Identifier(self._advance().value)
317: self._consume_semicolon()
318- return ContinueStatement(label)
319-
320- def _parse_return_statement(self) -> ReturnStatement:
321- """Parse return statement."""
322- argument = None
323- if not self._check(TokenType.SEMICOLON) and not self._check(TokenType.RBRACE):
324- argument = self._parse_expression()
325: self._consume_semicolon()
326- return ReturnStatement(argument)
327-
328- def _parse_throw_statement(self) -> ThrowStatement:
329- """Parse throw statement."""
330- argument = self._parse_expression()
331: self._consume_semicolon()
332- return ThrowStatement(argument)
333-
334- def _parse_try_statement(self) -> TryStatement:
335- """Parse try statement."""
336- block = self._parse_block_statement()
337- handler = None
338- finalizer = None
339-
340- if self._match(TokenType.CATCH):
341- self._expect(TokenType.LPAREN, "Expected '(' after 'catch'")
342- param = self._expect(TokenType.IDENTIFIER, "Expected catch parameter")
343- self._expect(TokenType.RPAREN, "Expected ')' after catch parameter")
344- catch_body = self._parse_block_statement()
345- handler = CatchClause(Identifier(param.value), catch_body)
346-
--
408: self._consume_semicolon()
409- return ExpressionStatement(expr)
410-
411: def _consume_semicolon(self) -> None:
412- """Consume a semicolon if present (ASI simulation)."""
413- self._match(TokenType.SEMICOLON)
414-
415- # ---- Expressions ----
416-
417- def _parse_expression(self, exclude_in: bool = False) -> Node:
418- """Parse an expression (includes comma operator)."""
419- expr = self._parse_assignment_expression(exclude_in)
420-
421- if self._check(TokenType.COMMA):
422- expressions = [expr]
423- while self._match(TokenType.COMMA):
424- expressions.append(self._parse_assignment_expression(exclude_in))
425- return SequenceExpression(expressions)
426-I see! The issue is in _parse_break_statement and _parse_continue_statement. They check if the next token is an identifier and consume it as a label. But according to JavaScript ASI rules:
break and continue have automatic semicolon insertion if the next token is on a new linebreak/continueSo I need to check if there's a newline between break/continue and the next token. If there is, don't try to parse a label.
Let me check how the lexer handles newlines.
{
"-i": true,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/lexer.py",
"pattern": "newline|linebreak|had_newline"
}The lexer doesn't track newlines. Let me check the Token class and see if there's line information.
{
"-A": 10,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/lexer.py",
"pattern": "class Token"
}{
"-A": 10,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python",
"pattern": "class Token"
}src/mquickjs_python/tokens.py:8:class TokenType(Enum):
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-9- """JavaScript token types."""
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-10-
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-11- # End of file
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-12- EOF = auto()
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-13-
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-14- # Literals
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-15- NUMBER = auto()
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-16- STRING = auto()
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-17- REGEX = auto()
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-18-
--
src/mquickjs_python/tokens.py:151:class Token:
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-152- """A token from the JavaScript source."""
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-153-
src/mquickjs_python/tokens.py-154- type: TokenType
src/mquickjs_python/tokens.py-155- value: Any
src/mquickjs_python/tokens.py-156- line: int
src/mquickjs_python/tokens.py-157- column: int
/home/user/mquickjs-python/src/mquickjs_python/tokens.py-158-
src/mquickjs_python/tokens.py-159- def __repr__(self) -> str:
src/mquickjs_python/tokens.py-160- if self.value is not None:
src/mquickjs_python/tokens.py-161- return f"Token({self.type.name}, {self.value!r}, {self.line}:{self.column})"Tokens have line and column information. I can use this to check if there's a line break between break/continue and the next token. I need to save the line number before advancing past break and compare it to the current token's line.
But wait - looking at the code again, when _parse_break_statement is called, the break keyword has already been consumed by _match. Let me check the implementation more carefully.
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/parser.py",
"limit": 30,
"offset": 70
} 70→ if self.current.type != token_type:
71→ raise self._error(message)
72→ return self._advance()
73→
74→ def _is_at_end(self) -> bool:
75→ """Check if we've reached the end of input."""
76→ return self.current.type == TokenType.EOF
77→
78→ def _is_keyword(self) -> bool:
79→ """Check if current token is a keyword (reserved word)."""
80→ # Keywords that can be used as property names in object literals
81→ keyword_types = {
82→ TokenType.IF, TokenType.ELSE, TokenType.FOR, TokenType.WHILE,
83→ TokenType.DO, TokenType.SWITCH, TokenType.CASE, TokenType.DEFAULT,
84→ TokenType.BREAK, TokenType.CONTINUE, TokenType.RETURN, TokenType.THROW,
85→ TokenType.TRY, TokenType.CATCH, TokenType.FINALLY, TokenType.FUNCTION,
86→ TokenType.VAR, TokenType.NEW, TokenType.DELETE, TokenType.TYPEOF,
87→ TokenType.IN, TokenType.OF, TokenType.INSTANCEOF, TokenType.THIS,
88→ TokenType.TRUE, TokenType.FALSE, TokenType.NULL, TokenType.VOID,
89→ }
90→ return self.current.type in keyword_types
91→
92→ def _peek_next(self) -> Token:
93→ """Peek at the next token without consuming it."""
94→ # Save current state
95→ saved_pos = self.lexer.pos
96→ saved_line = self.lexer.line
97→ saved_column = self.lexer.column
98→ saved_current = self.current
99→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I need to look at how _match works and track the previous token's line number. Let me read the relevant parts.
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/parser.py",
"limit": 20,
"offset": 55
} 55→ return self.previous
56→
57→ def _check(self, *types: TokenType) -> bool:
58→ """Check if current token is one of the given types."""
59→ return self.current.type in types
60→
61→ def _match(self, *types: TokenType) -> bool:
62→ """If current token matches, advance and return True."""
63→ if self._check(*types):
64→ self._advance()
65→ return True
66→ return False
67→
68→ def _expect(self, token_type: TokenType, message: str) -> Token:
69→ """Expect a specific token type or raise error."""
70→ if self.current.type != token_type:
71→ raise self._error(message)
72→ return self._advance()
73→
74→ def _is_at_end(self) -> bool:
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see - _advance saves the current token to self.previous. So after _match(TokenType.BREAK), self.previous contains the break token with its line number.
Now I need to modify _parse_break_statement to check if there's a newline between break and the next token. If self.current.line > self.previous.line, then there's a newline and we should NOT parse a label.
Let me also read the _parse_break_statement again to see the full context.
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/parser.py",
"limit": 20,
"offset": 303
}303→ 304→ def _parse_break_statement(self) -> BreakStatement: 305→ """Parse break statement.""" 306→ label = None 307→ if self._check(TokenType.IDENTIFIER): 308→ label = Identifier(self._advance().value) 309→ self._consume_semicolon() 310→ return BreakStatement(label) 311→ 312→ def _parse_continue_statement(self) -> ContinueStatement: 313→ """Parse continue statement.""" 314→ label = None 315→ if self._check(TokenType.IDENTIFIER): 316→ label = Identifier(self._advance().value) 317→ self._consume_semicolon() 318→ return ContinueStatement(label) 319→ 320→ def _parse_return_statement(self) -> ReturnStatement: 321→ """Parse return statement.""" 322→ argument = None <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
I need to fix both _parse_break_statement and _parse_continue_statement. They should only consume an identifier as a label if it's on the same line as break/continue.
Let me first add a test case for this ASI issue, then fix it.
{
"file_path": "/home/user/mquickjs-python/tests/test_vm.py",
"limit": 30,
"offset": 460
}<system-reminder>Warning: the file exists but is shorter than the provided offset (460). The file has 460 lines.</system-reminder>
{
"file_path": "/home/user/mquickjs-python/tests/test_vm.py",
"limit": 20,
"offset": 445
} 445→ ctx = JSContext()
446→ result = ctx.eval("var o = new Object(); o.x = 1; o.x")
447→ assert result == 1
448→
449→ def test_new_array(self):
450→ """new Array() creates array."""
451→ ctx = JSContext()
452→ result = ctx.eval("new Array(3).length")
453→ assert result == 3
454→
455→ def test_new_array_with_elements(self):
456→ """new Array(1, 2, 3) creates array with elements."""
457→ ctx = JSContext()
458→ result = ctx.eval("var a = new Array(1, 2, 3); a[1]")
459→ assert result == 2
460→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
def test_new_array_with_elements(self):
"""new Array(1, 2, 3) creates array with elements."""
ctx = JSContext()
result = ctx.eval("var a = new Array(1, 2, 3); a[1]")
assert result == 2 def test_new_array_with_elements(self):
"""new Array(1, 2, 3) creates array with elements."""
ctx = JSContext()
result = ctx.eval("var a = new Array(1, 2, 3); a[1]")
assert result == 2
class TestASI:
"""Test automatic semicolon insertion."""
def test_break_asi_newline(self):
"""break followed by identifier on new line should not consume identifier as label."""
ctx = JSContext()
# break should get ASI, i++ should be a separate statement
result = ctx.eval("""
var i = 0;
while (i < 3) {
if (i > 0)
break
i++
}
i
""")
assert result == 1
def test_continue_asi_newline(self):
"""continue followed by identifier on new line should not consume identifier as label."""
ctx = JSContext()
result = ctx.eval("""
var sum = 0;
for (var i = 0; i < 5; i++) {
if (i == 2)
continue
sum += i
}
sum
""")
# 0 + 1 + 3 + 4 = 8 (skipping 2)
assert result == 8The file /home/user/mquickjs-python/tests/test_vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
451→ ctx = JSContext()
452→ result = ctx.eval("new Array(3).length")
453→ assert result == 3
454→
455→ def test_new_array_with_elements(self):
456→ """new Array(1, 2, 3) creates array with elements."""
457→ ctx = JSContext()
458→ result = ctx.eval("var a = new Array(1, 2, 3); a[1]")
459→ assert result == 2
460→
461→
462→class TestASI:
463→ """Test automatic semicolon insertion."""
464→
465→ def test_break_asi_newline(self):
466→ """break followed by identifier on new line should not consume identifier as label."""
467→ ctx = JSContext()
468→ # break should get ASI, i++ should be a separate statement
469→ result = ctx.eval("""
470→ var i = 0;
471→ while (i < 3) {
472→ if (i > 0)
473→ break
474→ i++
475→ }
476→ i
477→ """)
478→ assert result == 1
479→
480→ def test_continue_asi_newline(self):
481→ """continue followed by identifier on new line should not consume identifier as label."""
482→ ctx = JSContext()
483→ result = ctx.eval("""
484→ var sum = 0;
485→ for (var i = 0; i < 5; i++) {
486→ if (i == 2)
487→ continue
488→ sum += i
489→ }
490→ sum
491→ """)
492→ # 0 + 1 + 3 + 4 = 8 (skipping 2)
493→ assert result == 8
494→Exit code 1
============================= test session starts ==============================
platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python
cachedir: .pytest_cache
rootdir: /home/user/mquickjs-python
configfile: pyproject.toml
collecting ... collected 2 items
tests/test_vm.py::TestASI::test_break_asi_newline FAILED [ 50%]
tests/test_vm.py::TestASI::test_continue_asi_newline FAILED [100%]
=================================== FAILURES ===================================
________________________ TestASI.test_break_asi_newline ________________________
self = <test_vm.TestASI object at 0x7eef4b060890>
def test_break_asi_newline(self):
"""break followed by identifier on new line should not consume identifier as label."""
ctx = JSContext()
# break should get ASI, i++ should be a separate statement
> result = ctx.eval("""
var i = 0;
while (i < 3) {
if (i > 0)
break
i++
}
i
""")
tests/test_vm.py:469:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
src/mquickjs_python/context.py:601: in eval
ast = parser.parse()
^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:114: in parse
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:136: in _parse_statement
return self._parse_while_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:221: in _parse_while_statement
body = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:127: in _parse_statement
return self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:182: in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:175: in _parse_statement
return self._parse_expression_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:407: in _parse_expression_statement
expr = self._parse_expression()
^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:419: in _parse_expression
expr = self._parse_assignment_expression(exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:441: in _parse_assignment_expression
expr = self._parse_conditional_expression(exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:546: in _parse_conditional_expression
expr = self._parse_binary_expression(0, exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:558: in _parse_binary_expression
left = self._parse_unary_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:657: in _parse_unary_expression
argument = self._parse_unary_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:660: in _parse_unary_expression
return self._parse_postfix_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:664: in _parse_postfix_expression
expr = self._parse_new_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:708: in _parse_new_expression
return self._parse_primary_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
self = <mquickjs_python.parser.Parser object at 0x7eef4acef590>
def _parse_primary_expression(self) -> Node:
"""Parse primary expression (literals, identifiers, grouped)."""
# Literals
if self._match(TokenType.NUMBER):
return NumericLiteral(self.previous.value)
if self._match(TokenType.STRING):
return StringLiteral(self.previous.value)
if self._match(TokenType.TRUE):
return BooleanLiteral(True)
if self._match(TokenType.FALSE):
return BooleanLiteral(False)
if self._match(TokenType.NULL):
return NullLiteral()
if self._match(TokenType.THIS):
return ThisExpression()
if self._match(TokenType.IDENTIFIER):
return Identifier(self.previous.value)
# Parenthesized expression
if self._match(TokenType.LPAREN):
expr = self._parse_expression()
self._expect(TokenType.RPAREN, "Expected ')' after expression")
return expr
# Array literal
if self._match(TokenType.LBRACKET):
return self._parse_array_literal()
# Object literal (need to be careful with block statements)
if self._match(TokenType.LBRACE):
return self._parse_object_literal()
# Function expression
i
... [884 characters truncated] ...
e should not consume identifier as label."""
ctx = JSContext()
> result = ctx.eval("""
var sum = 0;
for (var i = 0; i < 5; i++) {
if (i == 2)
continue
sum += i
}
sum
""")
tests/test_vm.py:483:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
src/mquickjs_python/context.py:601: in eval
ast = parser.parse()
^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:114: in parse
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:142: in _parse_statement
return self._parse_for_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:301: in _parse_for_statement
body = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:127: in _parse_statement
return self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:182: in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:175: in _parse_statement
return self._parse_expression_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:407: in _parse_expression_statement
expr = self._parse_expression()
^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:419: in _parse_expression
expr = self._parse_assignment_expression(exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:441: in _parse_assignment_expression
expr = self._parse_conditional_expression(exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:546: in _parse_conditional_expression
expr = self._parse_binary_expression(0, exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:558: in _parse_binary_expression
left = self._parse_unary_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:660: in _parse_unary_expression
return self._parse_postfix_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:664: in _parse_postfix_expression
expr = self._parse_new_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/mquickjs_python/parser.py:708: in _parse_new_expression
return self._parse_primary_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
self = <mquickjs_python.parser.Parser object at 0x7eef4ae2f910>
def _parse_primary_expression(self) -> Node:
"""Parse primary expression (literals, identifiers, grouped)."""
# Literals
if self._match(TokenType.NUMBER):
return NumericLiteral(self.previous.value)
if self._match(TokenType.STRING):
return StringLiteral(self.previous.value)
if self._match(TokenType.TRUE):
return BooleanLiteral(True)
if self._match(TokenType.FALSE):
return BooleanLiteral(False)
if self._match(TokenType.NULL):
return NullLiteral()
if self._match(TokenType.THIS):
return ThisExpression()
if self._match(TokenType.IDENTIFIER):
return Identifier(self.previous.value)
# Parenthesized expression
if self._match(TokenType.LPAREN):
expr = self._parse_expression()
self._expect(TokenType.RPAREN, "Expected ')' after expression")
return expr
# Array literal
if self._match(TokenType.LBRACKET):
return self._parse_array_literal()
# Object literal (need to be careful with block statements)
if self._match(TokenType.LBRACE):
return self._parse_object_literal()
# Function expression
if self._match(TokenType.FUNCTION):
return self._parse_function_expression()
# Regex literal - when we see / in primary expression context, it's a regex
if self._check(TokenType.SLASH):
regex_token = self.lexer.read_regex_literal()
self.current = self.lexer.next_token() # Move past the regex
pattern, flags = regex_token.value
return RegexLiteral(pattern, flags)
> raise self._error(f"Unexpected token: {self.current.type.name}")
E mquickjs_python.errors.JSSyntaxError: SyntaxError: Unexpected token: PLUS_ASSIGN
src/mquickjs_python/parser.py:769: JSSyntaxError
=========================== short test summary info ============================
FAILED tests/test_vm.py::TestASI::test_break_asi_newline - mquickjs_python.er...
FAILED tests/test_vm.py::TestASI::test_continue_asi_newline - mquickjs_python...
============================== 2 failed in 0.53s ===============================Both tests fail as expected. Now I need to fix the parser. The issue is in _parse_break_statement and _parse_continue_statement. They should only consume an identifier as a label if it's on the same line.
def _parse_break_statement(self) -> BreakStatement:
"""Parse break statement."""
label = None
if self._check(TokenType.IDENTIFIER):
label = Identifier(self._advance().value)
self._consume_semicolon()
return BreakStatement(label)
def _parse_continue_statement(self) -> ContinueStatement:
"""Parse continue statement."""
label = None
if self._check(TokenType.IDENTIFIER):
label = Identifier(self._advance().value)
self._consume_semicolon()
return ContinueStatement(label) def _parse_break_statement(self) -> BreakStatement:
"""Parse break statement."""
label = None
# Only consume identifier as label if on same line (ASI rule)
if self._check(TokenType.IDENTIFIER) and self.current.line == self.previous.line:
label = Identifier(self._advance().value)
self._consume_semicolon()
return BreakStatement(label)
def _parse_continue_statement(self) -> ContinueStatement:
"""Parse continue statement."""
label = None
# Only consume identifier as label if on same line (ASI rule)
if self._check(TokenType.IDENTIFIER) and self.current.line == self.previous.line:
label = Identifier(self._advance().value)
self._consume_semicolon()
return ContinueStatement(label)The file /home/user/mquickjs-python/src/mquickjs_python/parser.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 300→ 301→ body = self._parse_statement() 302→ return ForStatement(init, test, update, body) 303→ 304→ def _parse_break_statement(self) -> BreakStatement: 305→ """Parse break statement.""" 306→ label = None 307→ # Only consume identifier as label if on same line (ASI rule) 308→ if self._check(TokenType.IDENTIFIER) and self.current.line == self.previous.line: 309→ label = Identifier(self._advance().value) 310→ self._consume_semicolon() 311→ return BreakStatement(label) 312→ 313→ def _parse_continue_statement(self) -> ContinueStatement: 314→ """Parse continue statement.""" 315→ label = None 316→ # Only consume identifier as label if on same line (ASI rule) 317→ if self._check(TokenType.IDENTIFIER) and self.current.line == self.previous.line: 318→ label = Identifier(self._advance().value) 319→ self._consume_semicolon() 320→ return ContinueStatement(label) 321→ 322→ def _parse_return_statement(self) -> ReturnStatement: 323→ """Parse return statement.""" 324→ argument = None
============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python cachedir: .pytest_cache rootdir: /home/user/mquickjs-python configfile: pyproject.toml collecting ... collected 2 items tests/test_vm.py::TestASI::test_break_asi_newline PASSED [ 50%] tests/test_vm.py::TestASI::test_continue_asi_newline PASSED [100%] ============================== 2 passed in 0.06s ===============================
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval(open('tests/test_language.js').read())
print('SUCCESS')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1Progress! The syntax error is fixed, now there's a runtime error. The error is "Update expression on non-identifier" which is likely about ++ or -- on something other than a simple identifier (like a.x++ or arr[0]++).
Let me commit the current ASI fix, then work on the next issue.
tests/test_vm.py::TestGlobalAccess::test_set_global PASSED [ 95%] tests/test_vm.py::TestGlobalAccess::test_get_global PASSED [ 95%] tests/test_vm.py::TestVoidOperator::test_void_returns_undefined PASSED [ 96%] tests/test_vm.py::TestVoidOperator::test_void_expression PASSED [ 96%] tests/test_vm.py::TestVoidOperator::test_void_function_call PASSED [ 96%] tests/test_vm.py::TestForOf::test_for_of_array PASSED [ 96%] tests/test_vm.py::TestForOf::test_for_of_string PASSED [ 97%] tests/test_vm.py::TestGetterSetter::test_getter PASSED [ 97%] tests/test_vm.py::TestGetterSetter::test_setter PASSED [ 97%] tests/test_vm.py::TestGetterSetter::test_getter_setter_combined PASSED [ 97%] tests/test_vm.py::TestTryFinallyBreak::test_break_in_try_finally PASSED [ 98%] tests/test_vm.py::TestLabeledStatements::test_labeled_break_after_while PASSED [ 98%] tests/test_vm.py::TestLabeledStatements::test_labeled_break_in_block PASSED [ 98%] tests/test_vm.py::TestBuiltinConstructors::test_new_object PASSED [ 98%] tests/test_vm.py::TestBuiltinConstructors::test_new_array PASSED [ 99%] tests/test_vm.py::TestBuiltinConstructors::test_new_array_with_elements PASSED [ 99%] tests/test_vm.py::TestASI::test_break_asi_newline PASSED [ 99%] tests/test_vm.py::TestASI::test_continue_asi_newline PASSED [100%] ======================== 390 passed, 5 xfailed in 4.55s ========================
git add -A && git commit -m "$(cat <<'EOF' Fix ASI for break/continue with newline before identifier In JavaScript, break/continue followed by an identifier on a new line should trigger automatic semicolon insertion. The identifier should not be consumed as a label. Now checks if identifier is on the same line before treating it as a label. EOF )"
2 files changed, 38 insertions(+), 2 deletions(-)
Now let me work on the "Update expression on non-identifier" error. This is likely about a.x++ or arr[0]++.
{
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python",
"pattern": "Update expression on non-identifier"
}src/mquickjs_python/compiler.py:1189: raise NotImplementedError("Update expression on non-identifier"){
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 40,
"offset": 1170
} 1170→ else:
1171→ self._emit(OpCode.DUP)
1172→ self._emit(inc_op)
1173→ self._emit(OpCode.STORE_CLOSURE, closure_slot)
1174→ self._emit(OpCode.POP)
1175→ else:
1176→ idx = self._add_name(name)
1177→ self._emit(OpCode.LOAD_NAME, idx)
1178→ if node.prefix:
1179→ self._emit(inc_op)
1180→ self._emit(OpCode.DUP)
1181→ self._emit(OpCode.STORE_NAME, idx)
1182→ self._emit(OpCode.POP)
1183→ else:
1184→ self._emit(OpCode.DUP)
1185→ self._emit(inc_op)
1186→ self._emit(OpCode.STORE_NAME, idx)
1187→ self._emit(OpCode.POP)
1188→ else:
1189→ raise NotImplementedError("Update expression on non-identifier")
1190→
1191→ elif isinstance(node, BinaryExpression):
1192→ self._compile_expression(node.left)
1193→ self._compile_expression(node.right)
1194→ op_map = {
1195→ "+": OpCode.ADD,
1196→ "-": OpCode.SUB,
1197→ "*": OpCode.MUL,
1198→ "/": OpCode.DIV,
1199→ "%": OpCode.MOD,
1200→ "**": OpCode.POW,
1201→ "&": OpCode.BAND,
1202→ "|": OpCode.BOR,
1203→ "^": OpCode.BXOR,
1204→ "<<": OpCode.SHL,
1205→ ">>": OpCode.SHR,
1206→ ">>>": OpCode.USHR,
1207→ "<": OpCode.LT,
1208→ "<=": OpCode.LE,
1209→ ">": OpCode.GT,
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I need to see the full context of how UpdateExpression is handled. Let me read more before line 1170.
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 60,
"offset": 1135
} 1135→ self._emit(OpCode.LOAD_CELL, cell_slot)
1136→ if node.prefix:
1137→ self._emit(inc_op)
1138→ self._emit(OpCode.DUP)
1139→ self._emit(OpCode.STORE_CELL, cell_slot)
1140→ self._emit(OpCode.POP)
1141→ else:
1142→ self._emit(OpCode.DUP)
1143→ self._emit(inc_op)
1144→ self._emit(OpCode.STORE_CELL, cell_slot)
1145→ self._emit(OpCode.POP)
1146→ else:
1147→ slot = self._get_local(name)
1148→ if slot is not None:
1149→ self._emit(OpCode.LOAD_LOCAL, slot)
1150→ if node.prefix:
1151→ self._emit(inc_op)
1152→ self._emit(OpCode.DUP)
1153→ self._emit(OpCode.STORE_LOCAL, slot)
1154→ self._emit(OpCode.POP)
1155→ else:
1156→ self._emit(OpCode.DUP)
1157→ self._emit(inc_op)
1158→ self._emit(OpCode.STORE_LOCAL, slot)
1159→ self._emit(OpCode.POP)
1160→ else:
1161→ # Check if it's a free variable (from outer scope)
1162→ closure_slot = self._get_free_var(name)
1163→ if closure_slot is not None:
1164→ self._emit(OpCode.LOAD_CLOSURE, closure_slot)
1165→ if node.prefix:
1166→ self._emit(inc_op)
1167→ self._emit(OpCode.DUP)
1168→ self._emit(OpCode.STORE_CLOSURE, closure_slot)
1169→ self._emit(OpCode.POP)
1170→ else:
1171→ self._emit(OpCode.DUP)
1172→ self._emit(inc_op)
1173→ self._emit(OpCode.STORE_CLOSURE, closure_slot)
1174→ self._emit(OpCode.POP)
1175→ else:
1176→ idx = self._add_name(name)
1177→ self._emit(OpCode.LOAD_NAME, idx)
1178→ if node.prefix:
1179→ self._emit(inc_op)
1180→ self._emit(OpCode.DUP)
1181→ self._emit(OpCode.STORE_NAME, idx)
1182→ self._emit(OpCode.POP)
1183→ else:
1184→ self._emit(OpCode.DUP)
1185→ self._emit(inc_op)
1186→ self._emit(OpCode.STORE_NAME, idx)
1187→ self._emit(OpCode.POP)
1188→ else:
1189→ raise NotImplementedError("Update expression on non-identifier")
1190→
1191→ elif isinstance(node, BinaryExpression):
1192→ self._compile_expression(node.left)
1193→ self._compile_expression(node.right)
1194→ op_map = {
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I need to see more context to understand the full structure. Let me read before line 1135.
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 40,
"offset": 1105
} 1105→ self._emit(op_map[node.operator])
1106→ elif node.operator == "delete":
1107→ # Handle delete specially
1108→ if isinstance(node.argument, MemberExpression):
1109→ # Recompile as delete operation
1110→ self._compile_expression(node.argument.object)
1111→ if node.argument.computed:
1112→ self._compile_expression(node.argument.property)
1113→ else:
1114→ idx = self._add_constant(node.argument.property.name)
1115→ self._emit(OpCode.LOAD_CONST, idx)
1116→ self._emit(OpCode.DELETE_PROP)
1117→ else:
1118→ self._emit(OpCode.LOAD_TRUE) # delete on non-property returns true
1119→ elif node.operator == "void":
1120→ # void evaluates argument for side effects, returns undefined
1121→ self._emit(OpCode.POP) # Discard the argument value
1122→ self._emit(OpCode.LOAD_UNDEFINED)
1123→ else:
1124→ raise NotImplementedError(f"Unary operator: {node.operator}")
1125→
1126→ elif isinstance(node, UpdateExpression):
1127→ # ++x or x++
1128→ if isinstance(node.argument, Identifier):
1129→ name = node.argument.name
1130→ inc_op = OpCode.INC if node.operator == "++" else OpCode.DEC
1131→
1132→ # Check if it's a cell var (local that's captured by inner function)
1133→ cell_slot = self._get_cell_var(name)
1134→ if cell_slot is not None:
1135→ self._emit(OpCode.LOAD_CELL, cell_slot)
1136→ if node.prefix:
1137→ self._emit(inc_op)
1138→ self._emit(OpCode.DUP)
1139→ self._emit(OpCode.STORE_CELL, cell_slot)
1140→ self._emit(OpCode.POP)
1141→ else:
1142→ self._emit(OpCode.DUP)
1143→ self._emit(inc_op)
1144→ self._emit(OpCode.STORE_CELL, cell_slot)
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see the structure now. The UpdateExpression handler only handles Identifier. I need to add support for MemberExpression (like a.x++ or arr[0]++). Let me add this support.
For a MemberExpression like a.x++ (postfix):
1. Evaluate the object (push a)
2. If computed: evaluate the property
3. Otherwise: load property name as constant
4. DUP the object (need it later for store)
5. DUP2 (object, property) for GET_PROP
6. GET_PROP (get current value)
7. DUP (save current value for return)
8. INC/DEC
9. ROT (move result to correct position)
10. STORE_PROP
Actually this is complex. Let me think about it more carefully...
For postfix a.x++:
- Need to return old value
- Steps:
1. Push object a
2. Push property name "x"
3. DUP2 (duplicate object and property for later store)
4. GET_PROP (get current value, consumes one copy of object+property)
5. DUP (save for return value)
6. INC
7. Swap with the duplicated object/property
8. STORE_PROP
Actually let me look at how assignment is implemented for member expressions.
{
"-A": 5,
"-B": 5,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"pattern": "STORE_PROP"
}Maybe the opcode has a different name. Let me search for how member assignment works.
{
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python",
"pattern": "SET_PROP|STORE_ATTR"
}src/mquickjs_python/opcodes.py:30: SET_PROP = auto() # Set property: obj, key, value -> value src/mquickjs_python/compiler.py:480: # We need for SET_PROP: obj, prop, key -> value (leaves value on stack) src/mquickjs_python/compiler.py:492: self._emit(OpCode.SET_PROP) src/mquickjs_python/compiler.py:493: self._emit(OpCode.POP) # Pop the result of SET_PROP src/mquickjs_python/compiler.py:1308: self._emit(OpCode.SET_PROP) src/mquickjs_python/vm.py:258: elif op == OpCode.SET_PROP:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 30,
"offset": 475
} 475→ self._emit(OpCode.STORE_NAME, idx)
476→ self._emit(OpCode.POP)
477→ elif isinstance(node.left, MemberExpression):
478→ # for (obj.prop in ...) or for (obj[key] in ...)
479→ # After FOR_IN_NEXT: stack has [..., iterator, key]
480→ # We need for SET_PROP: obj, prop, key -> value (leaves value on stack)
481→ # Compile obj and prop first, then rotate key to top
482→ self._compile_expression(node.left.object)
483→ if node.left.computed:
484→ self._compile_expression(node.left.property)
485→ else:
486→ idx = self._add_constant(node.left.property.name)
487→ self._emit(OpCode.LOAD_CONST, idx)
488→ # Stack is now: [..., iterator, key, obj, prop]
489→ # We need: [..., iterator, obj, prop, key]
490→ # ROT3 on (key, obj, prop) gives (obj, prop, key)
491→ self._emit(OpCode.ROT3)
492→ self._emit(OpCode.SET_PROP)
493→ self._emit(OpCode.POP) # Pop the result of SET_PROP
494→ else:
495→ raise NotImplementedError(f"Unsupported for-in left: {type(node.left).__name__}")
496→
497→ self._compile_statement(node.body)
498→
499→ self._emit(OpCode.JUMP, loop_start)
500→ self._patch_jump(jump_done)
501→ self._emit(OpCode.POP) # Pop iterator
502→
503→ # Patch break and continue jumps
504→ for pos in loop_ctx.break_jumps:
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I understand the pattern now. For a.x++:
1. Stack should be: obj, prop, old_value (to return), new_value (for SET_PROP)
Actually let me look at how compound assignment works for member expressions, that's similar.
{
"-A": 30,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"pattern": "AssignmentExpression"
}9: ConditionalExpression, AssignmentExpression, SequenceExpression,
10- MemberExpression, CallExpression, NewExpression,
11- ExpressionStatement, BlockStatement, EmptyStatement,
12- VariableDeclaration, VariableDeclarator,
13- IfStatement, WhileStatement, DoWhileStatement, ForStatement,
14- ForInStatement, ForOfStatement, BreakStatement, ContinueStatement,
15- ReturnStatement, ThrowStatement, TryStatement, CatchClause,
16- SwitchStatement, SwitchCase, LabeledStatement,
17- FunctionDeclaration, FunctionExpression, ArrowFunctionExpression,
18-)
19-from .opcodes import OpCode
20-from .values import UNDEFINED
21-
22-
23-@dataclass
24-class CompiledFunction:
25- """A compiled function."""
26- name: str
27- params: List[str]
28- bytecode: bytes
29- constants: List[Any]
30- locals: List[str]
31- num_locals: int
32- free_vars: List[str] = field(default_factory=list) # Variables captured from outer scope
33- cell_vars: List[str] = field(default_factory=list) # Local variables that are captured by inner functions
34-
35-
36-@dataclass
37-class LoopContext:
38- """Context for loops (for break/continue)."""
39- break_jumps: List[int] = field(default_factory=list)
--
1249: elif isinstance(node, AssignmentExpression):
1250- if isinstance(node.left, Identifier):
1251- name = node.left.name
1252- if node.operator == "=":
1253- self._compile_expression(node.right)
1254- else:
1255- # Compound assignment - load current value first
1256- cell_slot = self._get_cell_var(name)
1257- if cell_slot is not None:
1258- self._emit(OpCode.LOAD_CELL, cell_slot)
1259- else:
1260- slot = self._get_local(name)
1261- if slot is not None:
1262- self._emit(OpCode.LOAD_LOCAL, slot)
1263- else:
1264- closure_slot = self._get_free_var(name)
1265- if closure_slot is not None:
1266- self._emit(OpCode.LOAD_CLOSURE, closure_slot)
1267- else:
1268- idx = self._add_name(name)
1269- self._emit(OpCode.LOAD_NAME, idx)
1270- self._compile_expression(node.right)
1271- op = node.operator[:-1] # Remove '='
1272- op_map = {
1273- "+": OpCode.ADD, "-": OpCode.SUB,
1274- "*": OpCode.MUL, "/": OpCode.DIV,
1275- "%": OpCode.MOD, "&": OpCode.BAND,
1276- "|": OpCode.BOR, "^": OpCode.BXOR,
1277- "<<": OpCode.SHL, ">>": OpCode.SHR,
1278- ">>>": OpCode.USHR,
1279- }{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 40,
"offset": 1285
}1285→ self._emit(OpCode.STORE_CELL, cell_slot) 1286→ else: 1287→ slot = self._get_local(name) 1288→ if slot is not None: 1289→ self._emit(OpCode.STORE_LOCAL, slot) 1290→ else: 1291→ closure_slot = self._get_free_var(name) 1292→ if closure_slot is not None: 1293→ self._emit(OpCode.STORE_CLOSURE, closure_slot) 1294→ else: 1295→ idx = self._add_name(name) 1296→ self._emit(OpCode.STORE_NAME, idx) 1297→ self._emit(OpCode.POP) 1298→ 1299→ elif isinstance(node.left, MemberExpression): 1300→ # obj.prop = value or obj[key] = value 1301→ self._compile_expression(node.left.object) 1302→ if node.left.computed: 1303→ self._compile_expression(node.left.property) 1304→ else: 1305→ idx = self._add_constant(node.left.property.name) 1306→ self._emit(OpCode.LOAD_CONST, idx) 1307→ self._compile_expression(node.right) 1308→ self._emit(OpCode.SET_PROP) 1309→ 1310→ elif isinstance(node, SequenceExpression): 1311→ for i, expr in enumerate(node.expressions): 1312→ self._compile_expression(expr) 1313→ if i < len(node.expressions) - 1: 1314→ self._emit(OpCode.POP) 1315→ 1316→ elif isinstance(node, MemberExpression): 1317→ self._compile_expression(node.object) 1318→ if node.computed: 1319→ self._compile_expression(node.property) 1320→ else: 1321→ idx = self._add_constant(node.property.name) 1322→ self._emit(OpCode.LOAD_CONST, idx) 1323→ self._emit(OpCode.GET_PROP) 1324→ <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
I see. For member assignment:
1. Compile object
2. Compile property (or load constant)
3. Compile value
4. SET_PROP (obj, prop, value -> value)
For UpdateExpression on member:
- For prefix ++a.x:
1. Compile object a
2. Compile property name "x"
3. DUP2 (copy obj and prop for GET_PROP)
4. GET_PROP (gets current value)
5. INC
6. The value is on top, with obj, prop underneath
7. SET_PROP (consumes obj, prop, new_value, leaves new_value)
8. Return new_value
a.x++:aActually let me check what DUP2 and ROT opcodes are available.
{
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/opcodes.py",
"pattern": "DUP|ROT"
}11: DUP = auto() # Duplicate top of stack 13: ROT3 = auto() # Rotate 3 items: a, b, c -> b, c, a
I don't have DUP2. Let me check if there's a way to implement this. I could: 1. Add DUP2 opcode 2. Use DUP multiple times with swapActually, for the update expression on member, I can be more clever. Let me think about this...
For a.x++:
1. Compile object -> [obj]
2. Compile property -> [obj, prop]
3. DUP the object -> [obj, prop, obj]
4. ROT3 -> [prop, obj, obj]
5. Hmm, this is getting complicated.
Let me just add a DUP2 opcode.
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/opcodes.py",
"limit": 20,
"offset": 1
} 1→"""Bytecode opcodes for the JavaScript VM."""
2→
3→from enum import IntEnum, auto
4→
5→
6→class OpCode(IntEnum):
7→ """Bytecode operation codes."""
8→
9→ # Stack operations
10→ POP = auto() # Pop and discard top of stack
11→ DUP = auto() # Duplicate top of stack
12→ SWAP = auto() # Swap top two stack items
13→ ROT3 = auto() # Rotate 3 items: a, b, c -> b, c, a
14→
15→ # Constants
16→ LOAD_CONST = auto() # Load constant from pool: arg = constant index
17→ LOAD_UNDEFINED = auto()
18→ LOAD_NULL = auto()
19→ LOAD_TRUE = auto()
20→ LOAD_FALSE = auto()
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
# Stack operations
POP = auto() # Pop and discard top of stack
DUP = auto() # Duplicate top of stack
SWAP = auto() # Swap top two stack items
ROT3 = auto() # Rotate 3 items: a, b, c -> b, c, a # Stack operations
POP = auto() # Pop and discard top of stack
DUP = auto() # Duplicate top of stack
DUP2 = auto() # Duplicate top two stack items: a, b -> a, b, a, b
SWAP = auto() # Swap top two stack items
ROT3 = auto() # Rotate 3 items: a, b, c -> b, c, a
ROT4 = auto() # Rotate 4 items: a, b, c, d -> b, c, d, aThe file /home/user/mquickjs-python/src/mquickjs_python/opcodes.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
5→
6→class OpCode(IntEnum):
7→ """Bytecode operation codes."""
8→
9→ # Stack operations
10→ POP = auto() # Pop and discard top of stack
11→ DUP = auto() # Duplicate top of stack
12→ DUP2 = auto() # Duplicate top two stack items: a, b -> a, b, a, b
13→ SWAP = auto() # Swap top two stack items
14→ ROT3 = auto() # Rotate 3 items: a, b, c -> b, c, a
15→ ROT4 = auto() # Rotate 4 items: a, b, c, d -> b, c, d, a
16→
17→ # Constants
18→ LOAD_CONST = auto() # Load constant from pool: arg = constant index
19→ LOAD_UNDEFINED = auto(){
"-A": 5,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "op == OpCode.DUP:"
}179: elif op == OpCode.DUP: 180- self.stack.append(self.stack[-1]) 181- 182- elif op == OpCode.SWAP: 183- self.stack[-1], self.stack[-2] = self.stack[-2], self.stack[-1] 184-
elif op == OpCode.DUP:
self.stack.append(self.stack[-1])
elif op == OpCode.SWAP:
self.stack[-1], self.stack[-2] = self.stack[-2], self.stack[-1] elif op == OpCode.DUP:
self.stack.append(self.stack[-1])
elif op == OpCode.DUP2:
# Duplicate top two items: a, b -> a, b, a, b
self.stack.append(self.stack[-2])
self.stack.append(self.stack[-2])
elif op == OpCode.SWAP:
self.stack[-1], self.stack[-2] = self.stack[-2], self.stack[-1]The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 175→ if op == OpCode.POP: 176→ if self.stack: 177→ self.stack.pop() 178→ 179→ elif op == OpCode.DUP: 180→ self.stack.append(self.stack[-1]) 181→ 182→ elif op == OpCode.DUP2: 183→ # Duplicate top two items: a, b -> a, b, a, b 184→ self.stack.append(self.stack[-2]) 185→ self.stack.append(self.stack[-2]) 186→ 187→ elif op == OpCode.SWAP: 188→ self.stack[-1], self.stack[-2] = self.stack[-2], self.stack[-1] 189→ 190→ elif op == OpCode.ROT3: 191→ # Rotate 3 items: a, b, c -> b, c, a 192→ a = self.stack[-3]
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 15,
"offset": 190
}190→ elif op == OpCode.ROT3: 191→ # Rotate 3 items: a, b, c -> b, c, a 192→ a = self.stack[-3] 193→ b = self.stack[-2] 194→ c = self.stack[-1] 195→ self.stack[-3] = b 196→ self.stack[-2] = c 197→ self.stack[-1] = a 198→ 199→ # Constants 200→ elif op == OpCode.LOAD_CONST: 201→ self.stack.append(frame.func.constants[arg]) 202→ 203→ elif op == OpCode.LOAD_UNDEFINED: 204→ self.stack.append(UNDEFINED) <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
elif op == OpCode.ROT3:
# Rotate 3 items: a, b, c -> b, c, a
a = self.stack[-3]
b = self.stack[-2]
c = self.stack[-1]
self.stack[-3] = b
self.stack[-2] = c
self.stack[-1] = a
# Constants elif op == OpCode.ROT3:
# Rotate 3 items: a, b, c -> b, c, a
a = self.stack[-3]
b = self.stack[-2]
c = self.stack[-1]
self.stack[-3] = b
self.stack[-2] = c
self.stack[-1] = a
elif op == OpCode.ROT4:
# Rotate 4 items: a, b, c, d -> b, c, d, a
a = self.stack[-4]
b = self.stack[-3]
c = self.stack[-2]
d = self.stack[-1]
self.stack[-4] = b
self.stack[-3] = c
self.stack[-2] = d
self.stack[-1] = a
# ConstantsThe file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 186→ 187→ elif op == OpCode.SWAP: 188→ self.stack[-1], self.stack[-2] = self.stack[-2], self.stack[-1] 189→ 190→ elif op == OpCode.ROT3: 191→ # Rotate 3 items: a, b, c -> b, c, a 192→ a = self.stack[-3] 193→ b = self.stack[-2] 194→ c = self.stack[-1] 195→ self.stack[-3] = b 196→ self.stack[-2] = c 197→ self.stack[-1] = a 198→ 199→ elif op == OpCode.ROT4: 200→ # Rotate 4 items: a, b, c, d -> b, c, d, a 201→ a = self.stack[-4] 202→ b = self.stack[-3] 203→ c = self.stack[-2] 204→ d = self.stack[-1] 205→ self.stack[-4] = b 206→ self.stack[-3] = c 207→ self.stack[-2] = d 208→ self.stack[-1] = a 209→ 210→ # Constants 211→ elif op == OpCode.LOAD_CONST: 212→ self.stack.append(frame.func.constants[arg]) 213→ 214→ elif op == OpCode.LOAD_UNDEFINED:
Now let me implement the UpdateExpression for MemberExpression in the compiler. First, let me write a test for it.
{
"file_path": "/home/user/mquickjs-python/tests/test_vm.py",
"limit": 10,
"offset": 488
}488→ sum += i 489→ } 490→ sum 491→ """) 492→ # 0 + 1 + 3 + 4 = 8 (skipping 2) 493→ assert result == 8 494→ <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
# 0 + 1 + 3 + 4 = 8 (skipping 2)
assert result == 8 # 0 + 1 + 3 + 4 = 8 (skipping 2)
assert result == 8
class TestMemberUpdate:
"""Test update expressions on member expressions."""
def test_object_property_postfix_increment(self):
"""a.x++ returns old value and increments."""
ctx = JSContext()
result = ctx.eval("""
var a = {x: 5};
var r = a.x++;
[r, a.x]
""")
assert result[0] == 5
assert result[1] == 6
def test_object_property_prefix_increment(self):
"""++a.x returns new value."""
ctx = JSContext()
result = ctx.eval("""
var a = {x: 5};
var r = ++a.x;
[r, a.x]
""")
assert result[0] == 6
assert result[1] == 6
def test_array_element_postfix_increment(self):
"""arr[0]++ works."""
ctx = JSContext()
result = ctx.eval("""
var arr = [10];
var r = arr[0]++;
[r, arr[0]]
""")
assert result[0] == 10
assert result[1] == 11
def test_object_property_decrement(self):
"""a.x-- works."""
ctx = JSContext()
result = ctx.eval("""
var a = {x: 5};
var r = a.x--;
[r, a.x]
""")
assert result[0] == 5
assert result[1] == 4The file /home/user/mquickjs-python/tests/test_vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
488→ sum += i
489→ }
490→ sum
491→ """)
492→ # 0 + 1 + 3 + 4 = 8 (skipping 2)
493→ assert result == 8
494→
495→
496→class TestMemberUpdate:
497→ """Test update expressions on member expressions."""
498→
499→ def test_object_property_postfix_increment(self):
500→ """a.x++ returns old value and increments."""
501→ ctx = JSContext()
502→ result = ctx.eval("""
503→ var a = {x: 5};
504→ var r = a.x++;
505→ [r, a.x]
506→ """)
507→ assert result[0] == 5
508→ assert result[1] == 6
509→
510→ def test_object_property_prefix_increment(self):
511→ """++a.x returns new value."""
512→ ctx = JSContext()
513→ result = ctx.eval("""
514→ var a = {x: 5};
515→ var r = ++a.x;
516→ [r, a.x]
517→ """)
518→ assert result[0] == 6
519→ assert result[1] == 6
520→
521→ def test_array_element_postfix_increment(self):
522→ """arr[0]++ works."""
523→ ctx = JSContext()
524→ result = ctx.eval("""
525→ var arr = [10];
526→ var r = arr[0]++;
527→ [r, arr[0]]
528→ """)
529→ assert result[0] == 10
530→ assert result[1] == 11
531→
532→ def test_object_property_decrement(self):
533→ """a.x-- works."""
534→ ctx = JSContext()
535→ result = ctx.eval("""
536→ var a = {x: 5};
537→ var r = a.x--;
538→ [r, a.x]
539→ """)
540→ assert result[0] == 5
541→ assert result[1] == 4
542→uv run pytest tests/test_vm.py::TestMemberUpdate::test_object_property_postfix_increment -v 2>&1 | tail -20
idx = self._add_name(name)
self._emit(OpCode.LOAD_NAME, idx)
if node.prefix:
self._emit(inc_op)
self._emit(OpCode.DUP)
self._emit(OpCode.STORE_NAME, idx)
self._emit(OpCode.POP)
else:
self._emit(OpCode.DUP)
self._emit(inc_op)
self._emit(OpCode.STORE_NAME, idx)
self._emit(OpCode.POP)
else:
> raise NotImplementedError("Update expression on non-identifier")
E NotImplementedError: Update expression on non-identifier
src/mquickjs_python/compiler.py:1189: NotImplementedError
=========================== short test summary info ============================
FAILED tests/test_vm.py::TestMemberUpdate::test_object_property_postfix_increment
============================== 1 failed in 0.30s =============================== else:
raise NotImplementedError("Update expression on non-identifier") elif isinstance(node.argument, MemberExpression):
# a.x++ or arr[i]++
inc_op = OpCode.INC if node.operator == "++" else OpCode.DEC
# Compile object
self._compile_expression(node.argument.object)
# Compile property (or load constant)
if node.argument.computed:
self._compile_expression(node.argument.property)
else:
idx = self._add_constant(node.argument.property.name)
self._emit(OpCode.LOAD_CONST, idx)
# Stack: [obj, prop]
self._emit(OpCode.DUP2) # [obj, prop, obj, prop]
self._emit(OpCode.GET_PROP) # [obj, prop, old_value]
if node.prefix:
# ++a.x: return new value
self._emit(inc_op) # [obj, prop, new_value]
self._emit(OpCode.DUP) # [obj, prop, new_value, new_value]
self._emit(OpCode.ROT4) # [new_value, obj, prop, new_value]
self._emit(OpCode.SET_PROP) # [new_value, new_value]
self._emit(OpCode.POP) # [new_value]
else:
# a.x++: return old value
self._emit(OpCode.DUP) # [obj, prop, old_value, old_value]
self._emit(inc_op) # [obj, prop, old_value, new_value]
self._emit(OpCode.ROT4) # [new_value, obj, prop, old_value]
self._emit(OpCode.ROT4) # [old_value, new_value, obj, prop]
self._emit(OpCode.ROT4) # [prop, old_value, new_value, obj]
self._emit(OpCode.ROT4) # [obj, prop, old_value, new_value]
# Hmm this is wrong. Let me think again...
# After DUP: [obj, prop, old_value, old_value]
# After inc: [obj, prop, old_value, new_value]
# We need: old_value on top, and do SET_PROP(obj, prop, new_value)
# ROT4 would give us: [prop, old_value, new_value, obj]
# That's not right either.
# Let me use SWAP instead: [obj, prop, new_value, old_value]
# Then ROT4: [prop, new_value, old_value, obj]
# Still not right.
# The issue is SET_PROP expects (obj, prop, val) and leaves val.
# Stack is [obj, prop, old_value, new_value]
# Need to move old_value out: [old_value, obj, prop, new_value]?
# No, after SET_PROP we'd have [old_value, new_value]
# We want only [old_value]
else:
raise NotImplementedError("Update expression on non-identifier")The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
1184→ self._emit(OpCode.DUP)
1185→ self._emit(inc_op)
1186→ self._emit(OpCode.STORE_NAME, idx)
1187→ self._emit(OpCode.POP)
1188→ elif isinstance(node.argument, MemberExpression):
1189→ # a.x++ or arr[i]++
1190→ inc_op = OpCode.INC if node.operator == "++" else OpCode.DEC
1191→
1192→ # Compile object
1193→ self._compile_expression(node.argument.object)
1194→ # Compile property (or load constant)
1195→ if node.argument.computed:
1196→ self._compile_expression(node.argument.property)
1197→ else:
1198→ idx = self._add_constant(node.argument.property.name)
1199→ self._emit(OpCode.LOAD_CONST, idx)
1200→
1201→ # Stack: [obj, prop]
1202→ self._emit(OpCode.DUP2) # [obj, prop, obj, prop]
1203→ self._emit(OpCode.GET_PROP) # [obj, prop, old_value]
1204→
1205→ if node.prefix:
1206→ # ++a.x: return new value
1207→ self._emit(inc_op) # [obj, prop, new_value]
1208→ self._emit(OpCode.DUP) # [obj, prop, new_value, new_value]
1209→ self._emit(OpCode.ROT4) # [new_value, obj, prop, new_value]
1210→ self._emit(OpCode.SET_PROP) # [new_value, new_value]
1211→ self._emit(OpCode.POP) # [new_value]
1212→ else:
1213→ # a.x++: return old value
1214→ self._emit(OpCode.DUP) # [obj, prop, old_value, old_value]
1215→ self._emit(inc_op) # [obj, prop, old_value, new_value]
1216→ self._emit(OpCode.ROT4) # [new_value, obj, prop, old_value]
1217→ self._emit(OpCode.ROT4) # [old_value, new_value, obj, prop]
1218→ self._emit(OpCode.ROT4) # [prop, old_value, new_value, obj]
1219→ self._emit(OpCode.ROT4) # [obj, prop, old_value, new_value]
1220→ # Hmm this is wrong. Let me think again...
1221→ # After DUP: [obj, prop, old_value, old_value]
1222→ # After inc: [obj, prop, old_value, new_value]
1223→ # We need: old_value on top, and do SET_PROP(obj, prop, new_value)
1224→ # ROT4 would give us: [prop, old_value, new_value, obj]
1225→ # That's not right either.
1226→ # Let me use SWAP instead: [obj, prop, new_value, old_value]
1227→ # Then ROT4: [prop, new_value, old_value, obj]
1228→ # Still not right.
1229→ # The issue is SET_PROP expects (obj, prop, val) and leaves val.
1230→ # Stack is [obj, prop, old_value, new_value]
1231→ # Need to move old_value out: [old_value, obj, prop, new_value]?
1232→ # No, after SET_PROP we'd have [old_value, new_value]
1233→ # We want only [old_value]
1234→ else:
1235→ raise NotImplementedError("Update expression on non-identifier")
1236→
1237→ elif isinstance(node, BinaryExpression):
1238→ self._compile_expression(node.left)
1239→ self._compile_expression(node.right)I left some incomplete code with comments. Let me think through the postfix case more carefully:For a.x++ we want to:
1. Get the old value of a.x
2. Increment it3. Store the new value back to a.x
4. Return the old valueStack operations:
1. Push obj: [obj]2. Push prop: [obj, prop]3. DUP2: [obj, prop, obj, prop]4. GET_PROP: [obj, prop, old_value]
5. DUP: [obj, prop, old_value, old_value] (save for return)6. INC: [obj, prop, old_value, new_value]Now we have [obj, prop, old_value, new_value] and need to do SET_PROP(obj, prop, new_value) and leave old_value on the stack.SET_PROP expects [obj, prop, value] and leaves [value].So we need to rearrange [obj, prop, old_value, new_value] to:- Have old_value saved somewhere- Call SET_PROP with [obj, prop, new_value]- End up with [old_value]One approach: use a different strategy. Save to a temp local variable? No, that's complex.
Alternative approach - use different stack manipulation:
1. Push obj: [obj]
2. Push prop: [obj, prop]
3. DUP2: [obj, prop, obj, prop]
4. GET_PROP: [obj, prop, old_value]
5. Now for postfix:
- Save obj, prop somewhere and inc old_value
- Actually, let me re-approach this...
Better approach:
1. Push obj: [obj]
2. DUP: [obj, obj]
3. Push prop: [obj, obj, prop]
4. DUP: [obj, obj, prop, prop]
5. ROT3: [obj, prop, obj, prop] - no this gets messy
I'm exploring a refined strategy for handling the postfix increment operation. The goal is to manipulate the stack to preserve the original value while incrementing. By duplicating key elements and carefully rearranging, I can track both the original and new values. The challenge is maintaining the correct stack state for object property updates.
The ROT4 operation rotates elements, shifting the stack's composition. This means after rotation, I'll need to carefully track the new stack arrangement to ensure the correct object, property, and incremented value are positioned for the SET_PROP operation. The key is preserving the original value while preparing the incremented value for assignment.
The final stack state needs to support returning the original value while updating the property, which requires precise stack manipulation through strategic rotations and duplications. I want to rearrange the stack to save the old value while preparing to set a new property value. By using SWAP, I'll first swap the old and new values. Then I'll need to use ROT4 to position the elements correctly for the property setting operation. The goal is to end up with a stack arrangement that preserves the old value and allows me to set the new value efficiently.
I'm exploring different rotation strategies to achieve the right stack manipulation. The key is finding a rotation that moves the old value to the desired position without losing any stack elements. Multiple ROT4 operations might help, but I'm considering a reverse rotation that shifts elements to the right instead of left.
My current approach involves experimenting with ROT4 and SWAP operations, testing how they transform the stack's order. I'm systematically checking each transformation to see if it matches my target arrangement, carefully tracking how each operation impacts the stack's configuration.
The goal is to develop a reliable method for repositioning stack elements precisely where I need them, which requires careful sequence of rotational moves.
By combining SWAP and multiple ROT4 operations, I've discovered a sequence that successfully rearranges the stack to [old_value, obj, prop, new_value]. This allows me to set a property while preserving the original object and tracking the transformation.
The key breakthrough is recognizing that three specific rotations, when paired with an initial SWAP, create the exact stack layout I require for my operation.
When SET_PROP executes, it consumes the top three stack elements, leaving precisely the result I want: the old value. This elegant manipulation gives me direct access to the previous state while updating the object.
elif isinstance(node.argument, MemberExpression):
# a.x++ or arr[i]++
inc_op = OpCode.INC if node.operator == "++" else OpCode.DEC
# Compile object
self._compile_expression(node.argument.object)
# Compile property (or load constant)
if node.argument.computed:
self._compile_expression(node.argument.property)
else:
idx = self._add_constant(node.argument.property.name)
self._emit(OpCode.LOAD_CONST, idx)
# Stack: [obj, prop]
self._emit(OpCode.DUP2) # [obj, prop, obj, prop]
self._emit(OpCode.GET_PROP) # [obj, prop, old_value]
if node.prefix:
# ++a.x: return new value
self._emit(inc_op) # [obj, prop, new_value]
self._emit(OpCode.DUP) # [obj, prop, new_value, new_value]
self._emit(OpCode.ROT4) # [new_value, obj, prop, new_value]
self._emit(OpCode.SET_PROP) # [new_value, new_value]
self._emit(OpCode.POP) # [new_value]
else:
# a.x++: return old value
self._emit(OpCode.DUP) # [obj, prop, old_value, old_value]
self._emit(inc_op) # [obj, prop, old_value, new_value]
self._emit(OpCode.ROT4) # [new_value, obj, prop, old_value]
self._emit(OpCode.ROT4) # [old_value, new_value, obj, prop]
self._emit(OpCode.ROT4) # [prop, old_value, new_value, obj]
self._emit(OpCode.ROT4) # [obj, prop, old_value, new_value]
# Hmm this is wrong. Let me think again...
# After DUP: [obj, prop, old_value, old_value]
# After inc: [obj, prop, old_value, new_value]
# We need: old_value on top, and do SET_PROP(obj, prop, new_value)
# ROT4 would give us: [prop, old_value, new_value, obj]
# That's not right either.
# Let me use SWAP instead: [obj, prop, new_value, old_value]
# Then ROT4: [prop, new_value, old_value, obj]
# Still not right.
# The issue is SET_PROP expects (obj, prop, val) and leaves val.
# Stack is [obj, prop, old_value, new_value]
# Need to move old_value out: [old_value, obj, prop, new_value]?
# No, after SET_PROP we'd have [old_value, new_value]
# We want only [old_value] elif isinstance(node.argument, MemberExpression):
# a.x++ or arr[i]++
inc_op = OpCode.INC if node.operator == "++" else OpCode.DEC
# Compile object
self._compile_expression(node.argument.object)
# Compile property (or load constant)
if node.argument.computed:
self._compile_expression(node.argument.property)
else:
idx = self._add_constant(node.argument.property.name)
self._emit(OpCode.LOAD_CONST, idx)
# Stack: [obj, prop]
self._emit(OpCode.DUP2) # [obj, prop, obj, prop]
self._emit(OpCode.GET_PROP) # [obj, prop, old_value]
if node.prefix:
# ++a.x: return new value
self._emit(inc_op) # [obj, prop, new_value]
self._emit(OpCode.DUP) # [obj, prop, new_value, new_value]
self._emit(OpCode.ROT4) # [new_value, obj, prop, new_value]
self._emit(OpCode.SET_PROP) # [new_value, new_value]
self._emit(OpCode.POP) # [new_value]
else:
# a.x++: return old value
self._emit(OpCode.DUP) # [obj, prop, old_value, old_value]
self._emit(inc_op) # [obj, prop, old_value, new_value]
# Rearrange: [obj, prop, old_value, new_value] -> [old_value, obj, prop, new_value]
self._emit(OpCode.SWAP) # [obj, prop, new_value, old_value]
self._emit(OpCode.ROT4) # [prop, new_value, old_value, obj]
self._emit(OpCode.ROT4) # [new_value, old_value, obj, prop]
self._emit(OpCode.ROT4) # [old_value, obj, prop, new_value]
self._emit(OpCode.SET_PROP) # [old_value, new_value]
self._emit(OpCode.POP) # [old_value]The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
1184→ self._emit(OpCode.DUP)
1185→ self._emit(inc_op)
1186→ self._emit(OpCode.STORE_NAME, idx)
1187→ self._emit(OpCode.POP)
1188→ elif isinstance(node.argument, MemberExpression):
1189→ # a.x++ or arr[i]++
1190→ inc_op = OpCode.INC if node.operator == "++" else OpCode.DEC
1191→
1192→ # Compile object
1193→ self._compile_expression(node.argument.object)
1194→ # Compile property (or load constant)
1195→ if node.argument.computed:
1196→ self._compile_expression(node.argument.property)
1197→ else:
1198→ idx = self._add_constant(node.argument.property.name)
1199→ self._emit(OpCode.LOAD_CONST, idx)
1200→
1201→ # Stack: [obj, prop]
1202→ self._emit(OpCode.DUP2) # [obj, prop, obj, prop]
1203→ self._emit(OpCode.GET_PROP) # [obj, prop, old_value]
1204→
1205→ if node.prefix:
1206→ # ++a.x: return new value
1207→ self._emit(inc_op) # [obj, prop, new_value]
1208→ self._emit(OpCode.DUP) # [obj, prop, new_value, new_value]
1209→ self._emit(OpCode.ROT4) # [new_value, obj, prop, new_value]
1210→ self._emit(OpCode.SET_PROP) # [new_value, new_value]
1211→ self._emit(OpCode.POP) # [new_value]
1212→ else:
1213→ # a.x++: return old value
1214→ self._emit(OpCode.DUP) # [obj, prop, old_value, old_value]
1215→ self._emit(inc_op) # [obj, prop, old_value, new_value]
1216→ # Rearrange: [obj, prop, old_value, new_value] -> [old_value, obj, prop, new_value]
1217→ self._emit(OpCode.SWAP) # [obj, prop, new_value, old_value]
1218→ self._emit(OpCode.ROT4) # [prop, new_value, old_value, obj]
1219→ self._emit(OpCode.ROT4) # [new_value, old_value, obj, prop]
1220→ self._emit(OpCode.ROT4) # [old_value, obj, prop, new_value]
1221→ self._emit(OpCode.SET_PROP) # [old_value, new_value]
1222→ self._emit(OpCode.POP) # [old_value]
1223→ else:
1224→ raise NotImplementedError("Update expression on non-identifier")
1225→
1226→ elif isinstance(node, BinaryExpression):Exit code 1
============================= test session starts ==============================
platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python
cachedir: .pytest_cache
rootdir: /home/user/mquickjs-python
configfile: pyproject.toml
collecting ... collected 4 items
tests/test_vm.py::TestMemberUpdate::test_object_property_postfix_increment PASSED [ 25%]
tests/test_vm.py::TestMemberUpdate::test_object_property_prefix_increment FAILED [ 50%]
tests/test_vm.py::TestMemberUpdate::test_array_element_postfix_increment PASSED [ 75%]
tests/test_vm.py::TestMemberUpdate::test_object_property_decrement PASSED [100%]
=================================== FAILURES ===================================
____________ TestMemberUpdate.test_object_property_prefix_increment ____________
self = <test_vm.TestMemberUpdate object at 0x7ee2bab87690>
def test_object_property_prefix_increment(self):
"""++a.x returns new value."""
ctx = JSContext()
result = ctx.eval("""
var a = {x: 5};
var r = ++a.x;
[r, a.x]
""")
> assert result[0] == 6
E AssertionError: assert 'x' == 6
tests/test_vm.py:518: AssertionError
=========================== short test summary info ============================
FAILED tests/test_vm.py::TestMemberUpdate::test_object_property_prefix_increment
========================= 1 failed, 3 passed in 0.23s ==========================The postfix case works but prefix fails. The result is 'x' which suggests something is wrong with the stack manipulation for the prefix case. Let me re-trace the prefix logic:For prefix ++a.x:1. Stack: [obj, prop]2. DUP2: [obj, prop, obj, prop]
3. GET_PROP: [obj, prop, old_value]4. INC: [obj, prop, new_value]5. DUP: [obj, prop, new_value, new_value]6. ROT4: [new_value, obj, prop, new_value]
Wait, my ROT4 does a, b, c, d -> b, c, d, a. So [obj, prop, new_value, new_value] becomes [prop, new_value, new_value, obj].
That's wrong! I expected the first new_value to be moved to position 0.
Let me trace more carefully. After step 5: Stack: [obj, prop, new_value, new_value] (indices -4, -3, -2, -1)
ROT4 does a, b, c, d -> b, c, d, a: - a = stack[-4] = obj - b = stack[-3] = prop - c = stack[-2] = new_value - d = stack[-1] = new_value - Result: [b, c, d, a] = [prop, new_value, new_value, obj]
So after ROT4 we have [prop, new_value, new_value, obj]. SET_PROP expects [obj, prop, value] and pops all 3, pushes value. But we have [prop, new_value, new_value, obj]. SET_PROP would try to set obj[new_value] = new_value! That's wrong.
I need the stack to be [new_value, obj, prop, new_value] so SET_PROP can use the top 3.
I'm exploring alternative stack manipulation strategies to correctly handle the prefix increment operation, focusing on rearranging the stack elements to match the expected input for SET_PROP.
Starting with two identical new_value elements, I'll use ROT4 rotations to strategically position the values. By performing three consecutive ROT4 operations, I can achieve the desired stack configuration: [new_value, obj, prop, new_value].
This approach ensures I have a saved copy of the new value at the bottom while maintaining the necessary elements for the SET_PROP operation. The rotations effectively shuffle the stack without losing any critical information.
After SET_PROP executes, I'll be left with a single new_value element, ready for further processing.
if node.prefix:
# ++a.x: return new value
self._emit(inc_op) # [obj, prop, new_value]
self._emit(OpCode.DUP) # [obj, prop, new_value, new_value]
self._emit(OpCode.ROT4) # [new_value, obj, prop, new_value]
self._emit(OpCode.SET_PROP) # [new_value, new_value]
self._emit(OpCode.POP) # [new_value] if node.prefix:
# ++a.x: return new value
self._emit(inc_op) # [obj, prop, new_value]
self._emit(OpCode.DUP) # [obj, prop, new_value, new_value]
# Rearrange: [obj, prop, nv, nv] -> [nv, obj, prop, nv]
self._emit(OpCode.ROT4) # [prop, nv, nv, obj]
self._emit(OpCode.ROT4) # [nv, nv, obj, prop]
self._emit(OpCode.ROT4) # [nv, obj, prop, nv]
self._emit(OpCode.SET_PROP) # [nv, nv]
self._emit(OpCode.POP) # [nv]The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 1201→ # Stack: [obj, prop] 1202→ self._emit(OpCode.DUP2) # [obj, prop, obj, prop] 1203→ self._emit(OpCode.GET_PROP) # [obj, prop, old_value] 1204→ 1205→ if node.prefix: 1206→ # ++a.x: return new value 1207→ self._emit(inc_op) # [obj, prop, new_value] 1208→ self._emit(OpCode.DUP) # [obj, prop, new_value, new_value] 1209→ # Rearrange: [obj, prop, nv, nv] -> [nv, obj, prop, nv] 1210→ self._emit(OpCode.ROT4) # [prop, nv, nv, obj] 1211→ self._emit(OpCode.ROT4) # [nv, nv, obj, prop] 1212→ self._emit(OpCode.ROT4) # [nv, obj, prop, nv] 1213→ self._emit(OpCode.SET_PROP) # [nv, nv] 1214→ self._emit(OpCode.POP) # [nv] 1215→ else: 1216→ # a.x++: return old value 1217→ self._emit(OpCode.DUP) # [obj, prop, old_value, old_value] 1218→ self._emit(inc_op) # [obj, prop, old_value, new_value]
============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python cachedir: .pytest_cache rootdir: /home/user/mquickjs-python configfile: pyproject.toml collecting ... collected 4 items tests/test_vm.py::TestMemberUpdate::test_object_property_postfix_increment PASSED [ 25%] tests/test_vm.py::TestMemberUpdate::test_object_property_prefix_increment PASSED [ 50%] tests/test_vm.py::TestMemberUpdate::test_array_element_postfix_increment PASSED [ 75%] tests/test_vm.py::TestMemberUpdate::test_object_property_decrement PASSED [100%] ============================== 4 passed in 0.07s ===============================
All member update tests pass. Let me now run the full test suite and then check test_language.js again.
tests/test_vm.py::TestVoidOperator::test_void_function_call PASSED [ 95%] tests/test_vm.py::TestForOf::test_for_of_array PASSED [ 95%] tests/test_vm.py::TestForOf::test_for_of_string PASSED [ 96%] tests/test_vm.py::TestGetterSetter::test_getter PASSED [ 96%] tests/test_vm.py::TestGetterSetter::test_setter PASSED [ 96%] tests/test_vm.py::TestGetterSetter::test_getter_setter_combined PASSED [ 96%] tests/test_vm.py::TestTryFinallyBreak::test_break_in_try_finally PASSED [ 97%] tests/test_vm.py::TestLabeledStatements::test_labeled_break_after_while PASSED [ 97%] tests/test_vm.py::TestLabeledStatements::test_labeled_break_in_block PASSED [ 97%] tests/test_vm.py::TestBuiltinConstructors::test_new_object PASSED [ 97%] tests/test_vm.py::TestBuiltinConstructors::test_new_array PASSED [ 98%] tests/test_vm.py::TestBuiltinConstructors::test_new_array_with_elements PASSED [ 98%] tests/test_vm.py::TestASI::test_break_asi_newline PASSED [ 98%] tests/test_vm.py::TestASI::test_continue_asi_newline PASSED [ 98%] tests/test_vm.py::TestMemberUpdate::test_object_property_postfix_increment PASSED [ 99%] tests/test_vm.py::TestMemberUpdate::test_object_property_prefix_increment PASSED [ 99%] tests/test_vm.py::TestMemberUpdate::test_array_element_postfix_increment PASSED [ 99%] tests/test_vm.py::TestMemberUpdate::test_object_property_decrement PASSED [100%] ======================== 394 passed, 5 xfailed in 4.61s ========================
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval(open('tests/test_language.js').read())
print('SUCCESS')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1FAILED: JSError: Error: assertion failed: got number:|2147483648|, expected number:|-2147483648| (1 << 31 === -2147483648)
The assertion is about 1 << 31 which should be -2147483648 (a negative number due to signed 32-bit integer overflow). The engine is returning 2147483648 (unsigned). This is a bitwise shift operation issue.Let me commit the current progress and then work on fixing this.
Good progress! The test runs but fails on a bitwise shift operation. Let me commit and continue:
git add -A && git commit -m "$(cat <<'EOF' Add update expressions for member expressions (a.x++, arr[i]--) Implemented prefix and postfix update expressions on member expressions: - Added DUP2 and ROT4 stack opcodes for manipulation - Compiles a.x++, ++a.x, arr[i]--, --arr[i] correctly - Postfix returns old value, prefix returns new value EOF )"
4 files changed, 104 insertions(+)
Now I need to fix the bitwise shift operators to work with signed 32-bit integers. The issue is 1 << 31 should be -2147483648 but we're getting 2147483648.Let me check how the shift operators are implemented.
{
"-A": 5,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "OpCode.SHL:"
}393: elif op == OpCode.SHL: 394- b = self.stack.pop() 395- a = self.stack.pop() 396- shift = self._to_uint32(b) & 0x1F 397- self.stack.append(self._to_int32(a) << shift) 398-
I see - the SHL operator is doing:1. Get the shift amount (masked to 5 bits, since shift > 31 wraps)2. Convert a to int32
3. Perform the shiftBut the result is not being converted to int32, so it can exceed 32 bits. In JavaScript, bitwise operators always return a signed 32-bit integer.Let me check to_int32.
{
"-A": 10,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "def _to_int32"
}665: def _to_int32(self, value: JSValue) -> int: 666- """Convert to 32-bit signed integer.""" 667- n = to_number(value) 668- if math.isnan(n) or math.isinf(n) or n == 0: 669- return 0 670- n = int(n) 671- n = n & 0xFFFFFFFF 672- if n >= 0x80000000: 673- n -= 0x100000000 674- return n 675-
I see the issue. The SHL operation does:1. Convert a to int32 (signed)2. Shift left3. But the result is NOT converted back to int32!So 1 << 31 becomes 0x80000000 = 2147483648, but it should be converted back to int32 which would be -2147483648.Let me fix the SHL to also convert the result to int32.
elif op == OpCode.SHL:
b = self.stack.pop()
a = self.stack.pop()
shift = self._to_uint32(b) & 0x1F
self.stack.append(self._to_int32(a) << shift) elif op == OpCode.SHL:
b = self.stack.pop()
a = self.stack.pop()
shift = self._to_uint32(b) & 0x1F
result = self._to_int32(a) << shift
# Convert result back to signed 32-bit
result = result & 0xFFFFFFFF
if result >= 0x80000000:
result -= 0x100000000
self.stack.append(result)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 389→ elif op == OpCode.BNOT: 390→ a = self.stack.pop() 391→ self.stack.append(~self._to_int32(a)) 392→ 393→ elif op == OpCode.SHL: 394→ b = self.stack.pop() 395→ a = self.stack.pop() 396→ shift = self._to_uint32(b) & 0x1F 397→ result = self._to_int32(a) << shift 398→ # Convert result back to signed 32-bit 399→ result = result & 0xFFFFFFFF 400→ if result >= 0x80000000: 401→ result -= 0x100000000 402→ self.stack.append(result) 403→ 404→ elif op == OpCode.SHR: 405→ b = self.stack.pop() 406→ a = self.stack.pop()
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
result = ctx.eval('1 << 31')
print(f'1 << 31 = {result}')
assert result == -2147483648
print('Test passed!')
" 2>&1The shift operator is now fixed. Let me also check if BNOT needs fixing - it might also need to convert the result to int32.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
result = ctx.eval('~1')
print(f'~1 = {result}')
assert result == -2
print('Test passed!')
" 2>&1BNOT works. But I should check - Python's ~ on a negative number won't necessarily give the right result because Python integers are arbitrary precision. Let me verify.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test various bitwise operations
tests = [
('1 << 31', -2147483648),
('1 << 30', 1073741824),
('~1', -2),
('~0', -1),
('(-4) >> 1', -2),
('(-4) >>> 1', 2147483646), # 0x7FFFFFFE
('-1 >>> 0', 4294967295),
]
for expr, expected in tests:
result = ctx.eval(expr)
if result != expected:
print(f'FAIL: {expr} = {result}, expected {expected}')
else:
print(f'PASS: {expr} = {result}')
" 2>&1PASS: 1 << 31 = -2147483648 PASS: 1 << 30 = 1073741824 PASS: ~1 = -2 PASS: ~0 = -1 PASS: (-4) >> 1 = -2 PASS: (-4) >>> 1 = 2147483646 PASS: -1 >>> 0 = 4294967295
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval(open('tests/test_language.js').read())
print('SUCCESS')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1FAILED: JSError: Error: assertion failed: got number:|Infinity|, expected number:|-Infinity|
There's another issue with -Infinity. Let me look at the test file to see what assertion fails.
143: assert(1/(-0.0), -Infinity); 145: assert(1/(-a), -Infinity); 146: assert(1/(0 * -6), -Infinity); 158: assert((Infinity | 0), 0); 159: assert(((-Infinity) | 0), 0); 167: assert((Infinity >>> 0), 0); 168: assert(((-Infinity) >>> 0), 0);
The issue is about -0 (negative zero). In JavaScript, 1 / -0 should be -Infinity, not Infinity. This is because negative zero is a special value.Let me check if negative zero is handled correctly.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test negative zero
tests = [
('1/(-0.0)', float('-inf')),
('var a = 0; 1/(-a)', float('-inf')),
('1/(0 * -6)', float('-inf')),
]
for expr, expected in tests:
result = ctx.eval(expr)
if result != expected:
print(f'FAIL: {expr} = {result}, expected {expected}')
else:
print(f'PASS: {expr} = {result}')
" 2>&1FAIL: 1/(-0.0) = inf, expected -inf FAIL: var a = 0; 1/(-a) = inf, expected -inf FAIL: 1/(0 * -6) = inf, expected -inf
The issue is with negative zero handling. In Python, -0.0 is stored differently from 0.0 but they're considered equal. Let me check how division is implemented.
uv run python -c "
# Test Python negative zero
import math
print(f'-0.0 = {-0.0}')
print(f'1 / -0.0 = {1 / -0.0}')
print(f'-0 == 0: {-0.0 == 0.0}')
print(f'math.copysign(1, -0.0) = {math.copysign(1, -0.0)}')
print(f'0 * -6 = {0 * -6}') # This might not be -0
print(f'0.0 * -6 = {0.0 * -6}') # This should be -0
print(f'1 / (0.0 * -6) = {1 / (0.0 * -6)}')
" 2>&1Exit code 1 -0.0 = -0.0 Traceback (most recent call last): File "<string>", line 5, in <module> ZeroDivisionError: float division by zero
Python raises a ZeroDivisionError but JavaScript returns Infinity. The JS VM must be handling division by zero specially. Let me check how DIV is implemented.
{
"-A": 15,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "OpCode.DIV:"
}335: elif op == OpCode.DIV:
336- b = self.stack.pop()
337- a = self.stack.pop()
338- b_num = to_number(b)
339- a_num = to_number(a)
340- if b_num == 0:
341- if a_num == 0:
342- self.stack.append(float('nan'))
343- elif a_num > 0:
344- self.stack.append(float('inf'))
345- else:
346- self.stack.append(float('-inf'))
347- else:
348- self.stack.append(a_num / b_num)
349-
350- elif op == OpCode.MOD:I see the issue. The DIV operation checks if b_num == 0, but doesn't distinguish between positive zero and negative zero. When dividing by negative zero, the result should be -Infinity for positive a and Infinity for negative a.The condition a_num > 0 gives Infinity, but it should be -Infinity when dividing by negative zero.I need to check the sign of zero. In Python, I can use math.copysign(1, x) to get the sign of x, including negative zero.
elif op == OpCode.DIV:
b = self.stack.pop()
a = self.stack.pop()
b_num = to_number(b)
a_num = to_number(a)
if b_num == 0:
if a_num == 0:
self.stack.append(float('nan'))
elif a_num > 0:
self.stack.append(float('inf'))
else:
self.stack.append(float('-inf'))
else:
self.stack.append(a_num / b_num) elif op == OpCode.DIV:
b = self.stack.pop()
a = self.stack.pop()
b_num = to_number(b)
a_num = to_number(a)
if b_num == 0:
# Check sign of zero using copysign
b_sign = math.copysign(1, b_num)
if a_num == 0:
self.stack.append(float('nan'))
elif (a_num > 0) == (b_sign > 0): # Same sign
self.stack.append(float('inf'))
else: # Different signs
self.stack.append(float('-inf'))
else:
self.stack.append(a_num / b_num)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
331→ b = self.stack.pop()
332→ a = self.stack.pop()
333→ self.stack.append(to_number(a) * to_number(b))
334→
335→ elif op == OpCode.DIV:
336→ b = self.stack.pop()
337→ a = self.stack.pop()
338→ b_num = to_number(b)
339→ a_num = to_number(a)
340→ if b_num == 0:
341→ # Check sign of zero using copysign
342→ b_sign = math.copysign(1, b_num)
343→ if a_num == 0:
344→ self.stack.append(float('nan'))
345→ elif (a_num > 0) == (b_sign > 0): # Same sign
346→ self.stack.append(float('inf'))
347→ else: # Different signs
348→ self.stack.append(float('-inf'))
349→ else:
350→ self.stack.append(a_num / b_num)
351→
352→ elif op == OpCode.MOD:
353→ b = self.stack.pop()
354→ a = self.stack.pop()Now I also need to handle the case of -0.0 literal. Let me test if (-0.0) produces negative zero in the parser.
uv run python -c "
from mquickjs_python import JSContext
import math
ctx = JSContext()
# Test negative zero
result = ctx.eval('-0.0')
print(f'-0.0 = {result}')
print(f'Sign of result: {math.copysign(1, result)}')
print(f'1 / (-0.0) = {ctx.eval(\"1/(-0.0)\")}')" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test negative zero
tests = [
('1/(-0.0)', float('-inf')),
('var a = 0; 1/(-a)', float('-inf')),
('1/(0 * -6)', float('-inf')),
]
for expr, expected in tests:
result = ctx.eval(expr)
if result != expected:
print(f'FAIL: {expr} = {result}, expected {expected}')
else:
print(f'PASS: {expr} = {result}')
" 2>&1PASS: 1/(-0.0) = -inf FAIL: var a = 0; 1/(-a) = inf, expected -inf FAIL: 1/(0 * -6) = inf, expected -inf
The issue is that unary negation and multiplication don't preserve negative zero. Let me check the unary negation.
{
"-A": 5,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "OpCode.NEG:"
}367: elif op == OpCode.NEG: 368- a = self.stack.pop() 369- self.stack.append(-to_number(a)) 370- 371- elif op == OpCode.POS: 372- a = self.stack.pop()
The NEG operation looks correct - it just negates the number. Let me check if the problem is with how 0 is stored. Maybe when we do var a = 0; -a, the variable a is stored as an integer 0, not a float 0.0.
uv run python -c "
import math
# Check if integer negation produces -0.0
a = 0
print(f'-a = {-a}')
print(f'type(-a) = {type(-a)}')
print(f'sign = {math.copysign(1, float(-a))}')
# With float
a = 0.0
print(f'-a = {-a}')
print(f'type(-a) = {type(-a)}')
print(f'sign = {math.copysign(1, -a)}')
" 2>&1-a = 0 type(-a) = <class 'int'> sign = 1.0 -a = -0.0 type(-a) = <class 'float'> sign = -1.0
The issue is that when you have an integer 0 and negate it, Python gives you integer 0, not float -0.0. But JavaScript always uses floating point for numbers.
I need to update the NEG operation to convert integers to floats first (or specifically handle the case of negating zero to produce -0.0).
elif op == OpCode.NEG:
a = self.stack.pop()
self.stack.append(-to_number(a)) elif op == OpCode.NEG:
a = self.stack.pop()
n = to_number(a)
# Ensure -0 produces -0.0 (float)
if n == 0:
self.stack.append(-0.0 if math.copysign(1, n) > 0 else 0.0)
else:
self.stack.append(-n)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 363→ b = self.stack.pop() 364→ a = self.stack.pop() 365→ self.stack.append(to_number(a) ** to_number(b)) 366→ 367→ elif op == OpCode.NEG: 368→ a = self.stack.pop() 369→ n = to_number(a) 370→ # Ensure -0 produces -0.0 (float) 371→ if n == 0: 372→ self.stack.append(-0.0 if math.copysign(1, n) > 0 else 0.0) 373→ else: 374→ self.stack.append(-n) 375→ 376→ elif op == OpCode.POS: 377→ a = self.stack.pop() 378→ self.stack.append(to_number(a))
uv run python -c "
import math
# Check multiplication with zero
print(f'0 * -6 = {0 * -6}')
print(f'0.0 * -6 = {0.0 * -6}')
print(f'sign = {math.copysign(1, 0.0 * -6)}')
" 2>&1I see - 0 * -6 with integer gives integer 0, but 0.0 * -6 gives -0.0. I need to ensure that multiplication produces floats when one operand is zero. Actually, I should ensure to_number returns a float when the value is 0.
{
"-A": 20,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python",
"pattern": "def to_number"
}src/mquickjs_python/values.py:114:def to_number(value: JSValue) -> Union[int, float]:
/home/user/mquickjs-python/src/mquickjs_python/values.py-115- """Convert a JavaScript value to number."""
src/mquickjs_python/values.py-116- if value is UNDEFINED:
/home/user/mquickjs-python/src/mquickjs_python/values.py-117- return float("nan")
src/mquickjs_python/values.py-118- if value is NULL:
/home/user/mquickjs-python/src/mquickjs_python/values.py-119- return 0
src/mquickjs_python/values.py-120- if isinstance(value, bool):
/home/user/mquickjs-python/src/mquickjs_python/values.py-121- return 1 if value else 0
src/mquickjs_python/values.py-122- if isinstance(value, (int, float)):
/home/user/mquickjs-python/src/mquickjs_python/values.py-123- return value
src/mquickjs_python/values.py-124- if isinstance(value, str):
/home/user/mquickjs-python/src/mquickjs_python/values.py-125- s = value.strip()
src/mquickjs_python/values.py-126- if s == "":
/home/user/mquickjs-python/src/mquickjs_python/values.py-127- return 0
src/mquickjs_python/values.py-128- try:
src/mquickjs_python/values.py-129- if "." in s or "e" in s.lower():
/home/user/mquickjs-python/src/mquickjs_python/values.py-130- return float(s)
src/mquickjs_python/values.py-131- if s.startswith("0x") or s.startswith("0X"):
/home/user/mquickjs-python/src/mquickjs_python/values.py-132- return int(s, 16)
src/mquickjs_python/values.py-133- if s.startswith("0o") or s.startswith("0O"):
/home/user/mquickjs-python/src/mquickjs_python/values.py-134- return int(s, 8)I see that to_number can return 0 (integer) for some cases. The issue is that multiplication of integer 0 with a negative number gives integer 0, not float -0.0.I could fix this in the multiplication operation by converting to float when the result is 0.
elif op == OpCode.MUL:
b = self.stack.pop()
a = self.stack.pop()
self.stack.append(to_number(a) * to_number(b)) elif op == OpCode.MUL:
b = self.stack.pop()
a = self.stack.pop()
a_num = float(to_number(a)) # Use float for proper -0 handling
b_num = float(to_number(b))
self.stack.append(a_num * b_num)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 326→ b = self.stack.pop() 327→ a = self.stack.pop() 328→ self.stack.append(to_number(a) - to_number(b)) 329→ 330→ elif op == OpCode.MUL: 331→ b = self.stack.pop() 332→ a = self.stack.pop() 333→ a_num = float(to_number(a)) # Use float for proper -0 handling 334→ b_num = float(to_number(b)) 335→ self.stack.append(a_num * b_num) 336→ 337→ elif op == OpCode.DIV: 338→ b = self.stack.pop() 339→ a = self.stack.pop()
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test negative zero
tests = [
('1/(-0.0)', float('-inf')),
('var a = 0; 1/(-a)', float('-inf')),
('1/(0 * -6)', float('-inf')),
]
for expr, expected in tests:
result = ctx.eval(expr)
if result != expected:
print(f'FAIL: {expr} = {result}, expected {expected}')
else:
print(f'PASS: {expr} = {result}')
" 2>&1All negative zero tests pass. Now let me run all tests and check test_language.js again.
.. [ 42%] tests/test_parser.py ................................................... [ 54%] ........ [ 56%] tests/test_regex.py .................................................... [ 69%] .................................... [ 78%] tests/test_string_regex.py ................... [ 83%] tests/test_vm.py ....................................................... [ 97%] .......... [100%] ======================== 394 passed, 5 xfailed in 4.59s ========================
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval(open('tests/test_language.js').read())
print('SUCCESS')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === \"object\") {
if (o === null)
return \"null\";
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (actual === expected) {
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === \"number\") {
if (isNaN(actual) && isNaN(expected))
return true;
}
if (typeof actual === \"object\") {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor
&& actual.toString() === expected.toString())
return;
}
}
throw_error(\"assertion failed: got \" +
get_full_type(actual) + \":|\" + actual + \"|\");
}
''')
# Test each function one by one
tests = [
'test_op1',
'test_cvt',
'test_eq',
'test_inc_dec',
'test_op2',
'test_prototype',
'test_arguments',
'test_to_primitive',
'test_labels',
'test_labels2',
]
for test in tests:
try:
ctx.eval(open('tests/test_language.js').read())
ctx.eval(f'{test}()')
print(f'PASS: {test}')
except Exception as e:
print(f'FAIL: {test} - {e}')
break
" 2>&1Exit code 1
Traceback (most recent call last):
File "<string>", line 4, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 601, in eval
ast = parser.parse()
^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 114, in parse
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 163, in _parse_statement
return self._parse_function_declaration()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 391, in _parse_function_declaration
body = self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 133, in _parse_statement
return self._parse_if_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 210, in _parse_if_statement
consequent = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 127, in _parse_statement
return self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 133, in _parse_statement
return self._parse_if_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 210, in _parse_if_statement
consequent = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 127, in _parse_statement
return self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 133, in _parse_statement
return self._parse_if_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 208, in _parse_if_statement
test = self._parse_expression()
^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 421, in _parse_expression
expr = self._parse_assignment_expression(exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 435, in _parse_assignment_expression
if self._is_arrow_function_single_param():
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 466, in _is_arrow_function_single_param
self._advance() # identifier
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 54, in _advance
self.current = self.lexer.next_token()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/lexer.py", line 388, in next_token
raise JSSyntaxError(f"Unexpected character: {ch!r}", line, column)
mquickjs_python.errors.JSSyntaxError: SyntaxError: Unexpected character: '\\'The issue is with parsing strings that have escape sequences with backslashes. The triple-quoted Python string contains backslashes that are being interpreted as escape sequences. Let me try a different approach.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Load the test file
code = open('tests/test_language.js').read()
# Find where it fails by splitting into functions
import re
functions = re.findall(r'function\s+(\w+)\s*\([^)]*\)\s*\{', code)
print('Found functions:', functions[:10])
"Found functions: ['throw_error', 'assert', 'get_full_type', 'assert_throws', 'test_op1', 'test_cvt', 'test_eq', 'test_inc_dec', 'F', 'test_op2']
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
import traceback
try:
ctx.eval(open('tests/test_language.js').read())
print('SUCCESS')
except Exception as e:
traceback.print_exc()
" 2>&1 | tail -20Traceback (most recent call last):
File "<string>", line 6, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 613, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 106, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 163, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 272, in _execute_opcode
self.stack.append(self._get_property(obj, key))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 758, in _get_property
raise JSTypeError(f"Cannot read property of {obj}")
mquickjs_python.errors.JSTypeError: TypeError: Cannot read property of undefinedThe error is during property access on undefined. Let me trace which test is failing. I'll simplify the debugging.
uv run python << 'PYTHON'
from mquickjs_python import JSContext
# Run tests one by one
tests = [
'test_op1',
'test_cvt',
'test_eq',
'test_inc_dec',
'test_op2',
'test_prototype',
'test_arguments',
'test_to_primitive',
'test_labels',
'test_labels2',
]
code = open('tests/test_language.js').read()
for i, test in enumerate(tests):
ctx = JSContext()
try:
# Run the file (defines all functions)
ctx.eval(code.split(test + '();')[0] + test + '();')
print(f'PASS: {test}')
except Exception as e:
print(f'FAIL: {test} - {e}')
PYTHON
PASS: test_op1 PASS: test_cvt PASS: test_eq PASS: test_inc_dec FAIL: test_op2 - TypeError: Cannot read property of undefined FAIL: test_prototype - TypeError: Cannot read property of undefined FAIL: test_arguments - TypeError: Cannot read property of undefined FAIL: test_to_primitive - TypeError: Cannot read property of undefined FAIL: test_labels - TypeError: Cannot read property of undefined FAIL: test_labels2 - TypeError: Cannot read property of undefined
Good, we got through test_op1, test_cvt, test_eq, and test_inc_dec. The failure starts at test_op2. Let me look at what test_op2 does.
uv run python << 'PYTHON'
from mquickjs_python import JSContext
ctx = JSContext()
# Minimal test_op2
ctx.eval('''
function F(x) {
this.x = x;
}
var a = new Object;
a.x = 1;
console.log("a.x =", a.x);
var b = new F(2);
console.log("b.x =", b.x);
console.log("b instanceof F:", b instanceof F);
''')
PYTHON
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 5, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 613, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 106, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 163, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 272, in _execute_opcode
self.stack.append(self._get_property(obj, key))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 758, in _get_property
raise JSTypeError(f"Cannot read property of {obj}")
mquickjs_python.errors.JSTypeError: TypeError: Cannot read property of undefined
a.x = 1The issue is with new F(2) where F is a user-defined function. Let me narrow it down.
uv run python << 'PYTHON'
from mquickjs_python import JSContext
ctx = JSContext()
# Step by step
ctx.eval('''
function F(x) {
this.x = x;
}
var b = new F(2);
console.log("b:", b);
console.log("b.x:", b.x);
''')
PYTHON
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 5, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 613, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 106, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 163, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 272, in _execute_opcode
self.stack.append(self._get_property(obj, key))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 758, in _get_property
raise JSTypeError(f"Cannot read property of {obj}")
mquickjs_python.errors.JSTypeError: TypeError: Cannot read property of undefined
b: undefinedThe result of new F(2) is undefined, which shouldn't be the case. Let me check how new is implemented.
uv run python << 'PYTHON'
from mquickjs_python import JSContext
ctx = JSContext()
# Simple test
result = ctx.eval('''
function F(x) {
this.x = x;
}
new F(2)
''')
print(f"Result: {result}")
print(f"Type: {type(result)}")
PYTHON
The result is None (undefined), but it should be the object. Let me check the _new_object implementation in the VM.
{
"-A": 50,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "def _new_object"
}1640: def _new_object(self, arg_count: int) -> None:
1641- """Create a new object with constructor."""
1642- args = []
1643- for _ in range(arg_count):
1644- args.insert(0, self.stack.pop())
1645- constructor = self.stack.pop()
1646-
1647- if isinstance(constructor, JSFunction):
1648- # Create new object
1649- obj = JSObject()
1650- # Call constructor with new object as 'this'
1651- self._invoke_js_function(constructor, args, obj)
1652- # Result is the new object (or returned value if object)
1653- self.stack.append(obj)
1654- elif isinstance(constructor, JSObject) and hasattr(constructor, '_call_fn'):
1655- # Built-in constructor (like Object, Array, RegExp)
1656- result = constructor._call_fn(*args)
1657- self.stack.append(result)
1658- else:
1659- raise JSTypeError(f"{constructor} is not a constructor")
1660-
1661- def _throw(self, exc: JSValue) -> None:
1662- """Throw an exception."""
1663- if self.exception_handlers:
1664- frame_idx, catch_ip = self.exception_handlers.pop()
1665-
1666- # Unwind call stack
1667- while len(self.call_stack) > frame_idx + 1:
1668- self.call_stack.pop()
1669-
1670- # Jump to catch handler
1671- frame = self.call_stack[-1]
1672- frame.ip = catch_ip
1673-
1674- # Push exception value
1675- self.stack.append(exc)
1676- else:
1677- # Uncaught exception
1678- if isinstance(exc, str):
1679- raise JSError(exc)
1680- elif isinstance(exc, JSObject):
1681- msg = exc.get("message")
1682- raise JSError(to_string(msg) if msg else "Error")
1683- else:
1684- raise JSError(to_string(exc))I see the issue. In _new_object, after calling _invoke_js_function, we push obj to the stack. But _invoke_js_function might also push the return value! Let me look at _invoke_js_function.
{
"-A": 30,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "def _invoke_js_function"
}1573: def _invoke_js_function(
1574- self,
1575- func: JSFunction,
1576- args: List[JSValue],
1577- this_val: JSValue,
1578- ) -> None:
1579- """Invoke a JavaScript function."""
1580- # Handle bound functions
1581- if hasattr(func, '_bound_this'):
1582- this_val = func._bound_this
1583- if hasattr(func, '_bound_args'):
1584- args = list(func._bound_args) + list(args)
1585- if hasattr(func, '_original_func'):
1586- func = func._original_func
1587-
1588- compiled = getattr(func, '_compiled', None)
1589- if compiled is None:
1590- raise JSTypeError("Function has no bytecode")
1591-
1592- # Prepare locals (parameters + arguments + local variables)
1593- locals_list = [UNDEFINED] * compiled.num_locals
1594- for i, arg in enumerate(args):
1595- if i < len(compiled.params):
1596- locals_list[i] = arg
1597-
1598- # Create 'arguments' object (stored after params in locals)
1599- # The 'arguments' slot is at index len(compiled.params)
1600- arguments_slot = len(compiled.params)
1601- if arguments_slot < compiled.num_locals:
1602- arguments_obj = JSArray()
1603- arguments_obj._elements = list(args){
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 45,
"offset": 1600
} 1600→ arguments_slot = len(compiled.params)
1601→ if arguments_slot < compiled.num_locals:
1602→ arguments_obj = JSArray()
1603→ arguments_obj._elements = list(args)
1604→ locals_list[arguments_slot] = arguments_obj
1605→
1606→ # For named function expressions, bind the function name to itself
1607→ # This allows recursive calls like: var f = function fact(n) { return fact(n-1); }
1608→ if compiled.name and compiled.name in compiled.locals:
1609→ name_slot = compiled.locals.index(compiled.name)
1610→ if name_slot >= len(compiled.params) + 1: # After params and arguments
1611→ locals_list[name_slot] = func
1612→
1613→ # Get closure cells from the function
1614→ closure_cells = getattr(func, '_closure_cells', None)
1615→
1616→ # Create cell storage for variables that will be captured by inner functions
1617→ cell_storage = None
1618→ if compiled.cell_vars:
1619→ cell_storage = []
1620→ for var_name in compiled.cell_vars:
1621→ # Find the initial value from locals
1622→ if var_name in compiled.locals:
1623→ slot = compiled.locals.index(var_name)
1624→ cell_storage.append(ClosureCell(locals_list[slot]))
1625→ else:
1626→ cell_storage.append(ClosureCell(UNDEFINED))
1627→
1628→ # Create new call frame
1629→ frame = CallFrame(
1630→ func=compiled,
1631→ ip=0,
1632→ bp=len(self.stack),
1633→ locals=locals_list,
1634→ this_value=this_val,
1635→ closure_cells=closure_cells,
1636→ cell_storage=cell_storage,
1637→ )
1638→ self.call_stack.append(frame)
1639→
1640→ def _new_object(self, arg_count: int) -> None:
1641→ """Create a new object with constructor."""
1642→ args = []
1643→ for _ in range(arg_count):
1644→ args.insert(0, self.stack.pop())
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see - _invoke_js_function doesn't wait for the function to complete. It just sets up a new call frame. So when we call _new_object, it sets up the call frame but then immediately pushes obj to the stack before the constructor has executed.
But wait, looking at the structure, _invoke_js_function pushes a frame to call_stack, and then the main _execute loop should continue executing. After the function returns, it should have returned an undefined value (if no explicit return), and then... hmm.
Actually, let me look at how CALL is implemented to understand the pattern.
{
"-A": 30,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "OpCode.CALL:"
}506: elif op == OpCode.CALL: 507- self._call_function(arg, None) 508- 509- elif op == OpCode.CALL_METHOD: 510- # Stack: this, method, arg1, arg2, ... 511- # Rearrange: this is before method 512- args = [] 513- for _ in range(arg): 514- args.insert(0, self.stack.pop()) 515- method = self.stack.pop() 516- this_val = self.stack.pop() 517- self._call_method(method, this_val, args) 518- 519- elif op == OpCode.RETURN: 520- result = self.stack.pop() if self.stack else UNDEFINED 521- self.call_stack.pop() 522- if self.call_stack: 523- self.stack.append(result) 524- else: 525- self.stack.append(result) 526- 527- elif op == OpCode.RETURN_UNDEFINED: 528- self.call_stack.pop() 529- if self.call_stack: 530- self.stack.append(UNDEFINED) 531- else: 532- self.stack.append(UNDEFINED) 533- 534- # Object operations 535- elif op == OpCode.NEW: 536- self._new_object(arg)
I see - the RETURN opcode handles the result. So the flow is:1. NEW calls _new_object2. _new_object creates an object and calls _invoke_js_function3. _invoke_js_function sets up a call frame4. The next iterations of _execute run the constructor code
5. Eventually the constructor returns (RETURN_UNDEFINED or RETURN)6. When RETURN happens, it pops the call frame and pushes the result
But wait, the issue is that _new_object pushes obj to the stack AFTER calling _invoke_js_function. But _invoke_js_function doesn't actually wait - it just sets up the frame. So the obj is pushed immediately, before the constructor runs.
The problem is timing. _new_object does:1. Setup and call _invoke_js_function2. Immediately pushes obj to stack
But the function hasn't run yet! The function runs in subsequent iterations of the _execute loop. When the function returns, it will push its return value on top of obj, but we're returning obj too early.I need to handle new differently. The constructor should run, and then we should check if it returned an object; if not, return the newly created object.
One approach: Instead of pushing obj immediately, we should:1. Set a flag that this is a constructor call 2. Store the new object somewhere 3. After the function returns, check if the return value is an object 4. If return value is an object, use it; otherwise use the created object
Actually, looking at the current code, it seems like the obj is pushed after _invoke_js_function, but the function hasn't actually executed yet. The _execute loop will continue and run the constructor, which will push its own return value. So we'd have two values on the stack!
Let me trace through what happens:1. _new_object(arg_count) is called
obj = JSObject()_invoke_js_function(constructor, args, obj) - this pushes a new frameobj to stack_new_object_execute continuesthis.x = x)The core problem is stack manipulation during object construction. When a constructor doesn't explicitly return an object, we want the newly created object to remain on the stack. However, the current implementation pushes UNDEFINED, which overwrites the original object. We need a mechanism to preserve the original object when no explicit return occurs.
I'll modify the call frame to track constructor calls. By adding a flag and storing the new object, we can ensure the correct object is returned. This approach mirrors how modern JavaScript engines handle object construction, checking if the constructor returns an object and falling back to the initially created instance if not.
The implementation will involve tracking the constructor call context and intelligently managing stack behavior during object instantiation.
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 20,
"offset": 30
} 30→ func: CompiledFunction
31→ ip: int # Instruction pointer
32→ bp: int # Base pointer (stack base for this frame)
33→ locals: List[JSValue]
34→ this_value: JSValue
35→ closure_cells: List[ClosureCell] = None # Cells for captured variables (from outer function)
36→ cell_storage: List[ClosureCell] = None # Cells for variables captured by inner functions
37→
38→
39→class ForInIterator:
40→ """Iterator for for-in loops."""
41→ def __init__(self, keys: List[str]):
42→ self.keys = keys
43→ self.index = 0
44→
45→ def next(self) -> Tuple[Optional[str], bool]:
46→ """Return (key, done)."""
47→ if self.index >= len(self.keys):
48→ return None, True
49→ key = self.keys[self.index]
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
func: CompiledFunction
ip: int # Instruction pointer
bp: int # Base pointer (stack base for this frame)
locals: List[JSValue]
this_value: JSValue
closure_cells: List[ClosureCell] = None # Cells for captured variables (from outer function)
cell_storage: List[ClosureCell] = None # Cells for variables captured by inner functions func: CompiledFunction
ip: int # Instruction pointer
bp: int # Base pointer (stack base for this frame)
locals: List[JSValue]
this_value: JSValue
closure_cells: List[ClosureCell] = None # Cells for captured variables (from outer function)
cell_storage: List[ClosureCell] = None # Cells for variables captured by inner functions
is_constructor_call: bool = False # True if this frame is from a "new" call
new_target: JSValue = None # The new object for constructor callsThe file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
26→
27→@dataclass
28→class CallFrame:
29→ """Call frame on the call stack."""
30→ func: CompiledFunction
31→ ip: int # Instruction pointer
32→ bp: int # Base pointer (stack base for this frame)
33→ locals: List[JSValue]
34→ this_value: JSValue
35→ closure_cells: List[ClosureCell] = None # Cells for captured variables (from outer function)
36→ cell_storage: List[ClosureCell] = None # Cells for variables captured by inner functions
37→ is_constructor_call: bool = False # True if this frame is from a "new" call
38→ new_target: JSValue = None # The new object for constructor calls
39→
40→
41→class ForInIterator:
42→ """Iterator for for-in loops."""Now I need to:
1. Update _new_object to NOT push the object immediately, but set the is_constructor_call flag
2. Update the RETURN/RETURN_UNDEFINED handlers to check for constructor calls
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 20,
"offset": 519
}519→ self._call_method(method, this_val, args) 520→ 521→ elif op == OpCode.RETURN: 522→ result = self.stack.pop() if self.stack else UNDEFINED 523→ self.call_stack.pop() 524→ if self.call_stack: 525→ self.stack.append(result) 526→ else: 527→ self.stack.append(result) 528→ 529→ elif op == OpCode.RETURN_UNDEFINED: 530→ self.call_stack.pop() 531→ if self.call_stack: 532→ self.stack.append(UNDEFINED) 533→ else: 534→ self.stack.append(UNDEFINED) 535→ 536→ # Object operations 537→ elif op == OpCode.NEW: 538→ self._new_object(arg) <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
elif op == OpCode.RETURN:
result = self.stack.pop() if self.stack else UNDEFINED
self.call_stack.pop()
if self.call_stack:
self.stack.append(result)
else:
self.stack.append(result)
elif op == OpCode.RETURN_UNDEFINED:
self.call_stack.pop()
if self.call_stack:
self.stack.append(UNDEFINED)
else:
self.stack.append(UNDEFINED) elif op == OpCode.RETURN:
result = self.stack.pop() if self.stack else UNDEFINED
popped_frame = self.call_stack.pop()
# For constructor calls, return the new object unless result is an object
if popped_frame.is_constructor_call:
if not isinstance(result, JSObject):
result = popped_frame.new_target
self.stack.append(result)
elif op == OpCode.RETURN_UNDEFINED:
popped_frame = self.call_stack.pop()
# For constructor calls, return the new object
if popped_frame.is_constructor_call:
self.stack.append(popped_frame.new_target)
else:
self.stack.append(UNDEFINED)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 517→ method = self.stack.pop() 518→ this_val = self.stack.pop() 519→ self._call_method(method, this_val, args) 520→ 521→ elif op == OpCode.RETURN: 522→ result = self.stack.pop() if self.stack else UNDEFINED 523→ popped_frame = self.call_stack.pop() 524→ # For constructor calls, return the new object unless result is an object 525→ if popped_frame.is_constructor_call: 526→ if not isinstance(result, JSObject): 527→ result = popped_frame.new_target 528→ self.stack.append(result) 529→ 530→ elif op == OpCode.RETURN_UNDEFINED: 531→ popped_frame = self.call_stack.pop() 532→ # For constructor calls, return the new object 533→ if popped_frame.is_constructor_call: 534→ self.stack.append(popped_frame.new_target) 535→ else: 536→ self.stack.append(UNDEFINED) 537→ 538→ # Object operations 539→ elif op == OpCode.NEW: 540→ self._new_object(arg)
Now I need to update _new_object to set the flag and not push obj immediately. I also need to update _invoke_js_function to accept these parameters.
def _new_object(self, arg_count: int) -> None:
"""Create a new object with constructor."""
args = []
for _ in range(arg_count):
args.insert(0, self.stack.pop())
constructor = self.stack.pop()
if isinstance(constructor, JSFunction):
# Create new object
obj = JSObject()
# Call constructor with new object as 'this'
self._invoke_js_function(constructor, args, obj)
# Result is the new object (or returned value if object)
self.stack.append(obj)
elif isinstance(constructor, JSObject) and hasattr(constructor, '_call_fn'):
# Built-in constructor (like Object, Array, RegExp)
result = constructor._call_fn(*args)
self.stack.append(result)
else:
raise JSTypeError(f"{constructor} is not a constructor") def _new_object(self, arg_count: int) -> None:
"""Create a new object with constructor."""
args = []
for _ in range(arg_count):
args.insert(0, self.stack.pop())
constructor = self.stack.pop()
if isinstance(constructor, JSFunction):
# Create new object
obj = JSObject()
# Set prototype from constructor's prototype property
if hasattr(constructor, '_prototype'):
obj._prototype = constructor._prototype
# Call constructor with new object as 'this'
# Mark this as a constructor call so RETURN knows to return the object
self._invoke_js_function(constructor, args, obj, is_constructor=True, new_target=obj)
# Don't push obj here - RETURN/RETURN_UNDEFINED will handle it
elif isinstance(constructor, JSObject) and hasattr(constructor, '_call_fn'):
# Built-in constructor (like Object, Array, RegExp)
result = constructor._call_fn(*args)
self.stack.append(result)
else:
raise JSTypeError(f"{constructor} is not a constructor")The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
1640→ cell_storage=cell_storage,
1641→ )
1642→ self.call_stack.append(frame)
1643→
1644→ def _new_object(self, arg_count: int) -> None:
1645→ """Create a new object with constructor."""
1646→ args = []
1647→ for _ in range(arg_count):
1648→ args.insert(0, self.stack.pop())
1649→ constructor = self.stack.pop()
1650→
1651→ if isinstance(constructor, JSFunction):
1652→ # Create new object
1653→ obj = JSObject()
1654→ # Set prototype from constructor's prototype property
1655→ if hasattr(constructor, '_prototype'):
1656→ obj._prototype = constructor._prototype
1657→ # Call constructor with new object as 'this'
1658→ # Mark this as a constructor call so RETURN knows to return the object
1659→ self._invoke_js_function(constructor, args, obj, is_constructor=True, new_target=obj)
1660→ # Don't push obj here - RETURN/RETURN_UNDEFINED will handle it
1661→ elif isinstance(constructor, JSObject) and hasattr(constructor, '_call_fn'):
1662→ # Built-in constructor (like Object, Array, RegExp)
1663→ result = constructor._call_fn(*args)
1664→ self.stack.append(result)
1665→ else:
1666→ raise JSTypeError(f"{constructor} is not a constructor")
1667→
1668→ def _throw(self, exc: JSValue) -> None:
1669→ """Throw an exception."""
1670→ if self.exception_handlers: def _invoke_js_function(
self,
func: JSFunction,
args: List[JSValue],
this_val: JSValue,
) -> None: def _invoke_js_function(
self,
func: JSFunction,
args: List[JSValue],
this_val: JSValue,
is_constructor: bool = False,
new_target: JSValue = None,
) -> None:The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
1573→ return result if result is not None else UNDEFINED
1574→ else:
1575→ raise JSTypeError(f"{callback} is not a function")
1576→
1577→ def _invoke_js_function(
1578→ self,
1579→ func: JSFunction,
1580→ args: List[JSValue],
1581→ this_val: JSValue,
1582→ is_constructor: bool = False,
1583→ new_target: JSValue = None,
1584→ ) -> None:
1585→ """Invoke a JavaScript function."""
1586→ # Handle bound functions
1587→ if hasattr(func, '_bound_this'):
1588→ this_val = func._bound_this{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 25,
"offset": 1625
}1625→ cell_storage = [] 1626→ for var_name in compiled.cell_vars: 1627→ # Find the initial value from locals 1628→ if var_name in compiled.locals: 1629→ slot = compiled.locals.index(var_name) 1630→ cell_storage.append(ClosureCell(locals_list[slot])) 1631→ else: 1632→ cell_storage.append(ClosureCell(UNDEFINED)) 1633→ 1634→ # Create new call frame 1635→ frame = CallFrame( 1636→ func=compiled, 1637→ ip=0, 1638→ bp=len(self.stack), 1639→ locals=locals_list, 1640→ this_value=this_val, 1641→ closure_cells=closure_cells, 1642→ cell_storage=cell_storage, 1643→ ) 1644→ self.call_stack.append(frame) 1645→ 1646→ def _new_object(self, arg_count: int) -> None: 1647→ """Create a new object with constructor.""" 1648→ args = [] 1649→ for _ in range(arg_count): <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
# Create new call frame
frame = CallFrame(
func=compiled,
ip=0,
bp=len(self.stack),
locals=locals_list,
this_value=this_val,
closure_cells=closure_cells,
cell_storage=cell_storage,
)
self.call_stack.append(frame) # Create new call frame
frame = CallFrame(
func=compiled,
ip=0,
bp=len(self.stack),
locals=locals_list,
this_value=this_val,
closure_cells=closure_cells,
cell_storage=cell_storage,
is_constructor_call=is_constructor,
new_target=new_target,
)
self.call_stack.append(frame)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 1630→ cell_storage.append(ClosureCell(locals_list[slot])) 1631→ else: 1632→ cell_storage.append(ClosureCell(UNDEFINED)) 1633→ 1634→ # Create new call frame 1635→ frame = CallFrame( 1636→ func=compiled, 1637→ ip=0, 1638→ bp=len(self.stack), 1639→ locals=locals_list, 1640→ this_value=this_val, 1641→ closure_cells=closure_cells, 1642→ cell_storage=cell_storage, 1643→ is_constructor_call=is_constructor, 1644→ new_target=new_target, 1645→ ) 1646→ self.call_stack.append(frame) 1647→ 1648→ def _new_object(self, arg_count: int) -> None: 1649→ """Create a new object with constructor.""" 1650→ args = []
uv run python << 'PYTHON'
from mquickjs_python import JSContext
ctx = JSContext()
result = ctx.eval('''
function F(x) {
this.x = x;
}
var b = new F(2);
b.x
''')
print(f"Result: {result}")
PYTHON
.. [ 42%] tests/test_parser.py ................................................... [ 54%] ........ [ 56%] tests/test_regex.py .................................................... [ 69%] .................................... [ 78%] tests/test_string_regex.py ................... [ 83%] tests/test_vm.py ....................................................... [ 97%] .......... [100%] ======================== 394 passed, 5 xfailed in 4.57s ========================
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval(open('tests/test_language.js').read())
print('SUCCESS')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1Great progress! Now the error is about instanceof. Let me commit the current fixes and then implement instanceof.
git add -A && git commit -m "$(cat <<'EOF' Fix signed 32-bit left shift and negative zero handling - SHL now converts result back to signed 32-bit integer - DIV correctly handles negative zero divisor - NEG produces -0.0 when negating positive zero - MUL uses floats for proper -0.0 handling Also fix constructor calls (new F(x)): - Constructor calls now properly return the new object - Added is_constructor_call and new_target to CallFrame - RETURN/RETURN_UNDEFINED check for constructor calls EOF )"
1 file changed, 41 insertions(+), 16 deletions(-)
Now let me check the instanceof error. The error says "Right-hand side of instanceof is not callable", which means the instanceof operator is checking if the right-hand side is callable. Let me check how instanceof is implemented.
{
"-A": 20,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "OpCode.INSTANCEOF"
}479: elif op == OpCode.INSTANCEOF:
480- constructor = self.stack.pop()
481- obj = self.stack.pop()
482- # Simplified instanceof
483- if not isinstance(constructor, JSFunction):
484- raise JSTypeError("Right-hand side of instanceof is not callable")
485- self.stack.append(isinstance(obj, JSObject))
486-
487- elif op == OpCode.IN:
488- obj = self.stack.pop()
489- key = self.stack.pop()
490- if not isinstance(obj, JSObject):
491- raise JSTypeError("Cannot use 'in' operator on non-object")
492- key_str = to_string(key)
493- self.stack.append(obj.has(key_str))
494-
495- # Control flow
496- elif op == OpCode.JUMP:
497- frame.ip = arg
498-
499- elif op == OpCode.JUMP_IF_FALSE:I see - the instanceof implementation only checks for JSFunction, but constructors can also be JSCallableObject (like the built-in Object, Array). Let me also fix the actual instanceof logic - right now it just returns isinstance(obj, JSObject) which is always true for objects, but it should check the prototype chain.Let me improve the instanceof implementation.
elif op == OpCode.INSTANCEOF:
constructor = self.stack.pop()
obj = self.stack.pop()
# Simplified instanceof
if not isinstance(constructor, JSFunction):
raise JSTypeError("Right-hand side of instanceof is not callable")
self.stack.append(isinstance(obj, JSObject)) elif op == OpCode.INSTANCEOF:
constructor = self.stack.pop()
obj = self.stack.pop()
# Check if constructor is callable
if not (isinstance(constructor, JSFunction) or
(isinstance(constructor, JSObject) and hasattr(constructor, '_call_fn'))):
raise JSTypeError("Right-hand side of instanceof is not callable")
# Check prototype chain
if not isinstance(obj, JSObject):
self.stack.append(False)
else:
# Get constructor's prototype property
if isinstance(constructor, JSFunction) and hasattr(constructor, '_prototype'):
proto = constructor._prototype
elif isinstance(constructor, JSObject) and hasattr(constructor, '_prototype'):
proto = constructor._prototype
else:
proto = constructor.get("prototype") if isinstance(constructor, JSObject) else None
# Walk the prototype chain
result = False
current = getattr(obj, '_prototype', None)
while current is not None:
if current is proto:
result = True
break
current = getattr(current, '_prototype', None)
self.stack.append(result)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
475→ elif op == OpCode.TYPEOF:
476→ a = self.stack.pop()
477→ self.stack.append(js_typeof(a))
478→
479→ elif op == OpCode.INSTANCEOF:
480→ constructor = self.stack.pop()
481→ obj = self.stack.pop()
482→ # Check if constructor is callable
483→ if not (isinstance(constructor, JSFunction) or
484→ (isinstance(constructor, JSObject) and hasattr(constructor, '_call_fn'))):
485→ raise JSTypeError("Right-hand side of instanceof is not callable")
486→
487→ # Check prototype chain
488→ if not isinstance(obj, JSObject):
489→ self.stack.append(False)
490→ else:
491→ # Get constructor's prototype property
492→ if isinstance(constructor, JSFunction) and hasattr(constructor, '_prototype'):
493→ proto = constructor._prototype
494→ elif isinstance(constructor, JSObject) and hasattr(constructor, '_prototype'):
495→ proto = constructor._prototype
496→ else:
497→ proto = constructor.get("prototype") if isinstance(constructor, JSObject) else None
498→
499→ # Walk the prototype chain
500→ result = False
501→ current = getattr(obj, '_prototype', None)
502→ while current is not None:
503→ if current is proto:
504→ result = True
505→ break
506→ current = getattr(current, '_prototype', None)
507→ self.stack.append(result)
508→
509→ elif op == OpCode.IN:
510→ obj = self.stack.pop()
511→ key = self.stack.pop()Now I need to make sure that when functions are created, they have a _prototype property. Let me check how functions are created and ensure they have a prototype.
uv run python << 'PYTHON'
from mquickjs_python import JSContext
ctx = JSContext()
result = ctx.eval('''
function F(x) {
this.x = x;
}
var b = new F(2);
b instanceof F
''')
print(f"Result: {result}")
PYTHON
The result is False when it should be True. The issue is that the function's prototype is not being set up correctly, or the new object's prototype is not pointing to it.Let me trace through what happens:1. When F is defined, it should have a prototype property which is an object2. When new F(2) is called, the new object's _prototype should be set to F.prototype3. When checking b instanceof F, we compare b._prototype with F.prototypeLet me check how functions are created and what prototype they have.
{
"-A": 10,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/values.py",
"pattern": "JSFunction"
}65: "JSFunction", 66-] 67- 68- 69-def is_nan(value: Any) -> bool: 70- """Check if value is NaN.""" 71- return isinstance(value, float) and math.isnan(value) 72- 73- 74-def is_infinity(value: Any) -> bool: 75- """Check if value is positive or negative infinity.""" -- 91: if isinstance(value, JSFunction): 92- return "function" 93- if isinstance(value, JSObject): 94- return "object" 95- return "undefined" 96- 97- 98-def to_boolean(value: JSValue) -> bool: 99- """Convert a JavaScript value to boolean.""" 100- if value is UNDEFINED or value is NULL: 101- return False -- 301:class JSFunction: 302- """JavaScript function (closure).""" 303- 304- def __init__( 305- self, 306- name: str, 307- params: List[str], 308- bytecode: bytes, 309- closure_vars: Optional[Dict[str, JSValue]] = None, 310- ): 311- self.name = name
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/values.py",
"limit": 30,
"offset": 301
} 301→class JSFunction:
302→ """JavaScript function (closure)."""
303→
304→ def __init__(
305→ self,
306→ name: str,
307→ params: List[str],
308→ bytecode: bytes,
309→ closure_vars: Optional[Dict[str, JSValue]] = None,
310→ ):
311→ self.name = name
312→ self.params = params
313→ self.bytecode = bytecode
314→ self.closure_vars = closure_vars or {}
315→
316→ def __repr__(self) -> str:
317→ return f"[Function: {self.name}]" if self.name else "[Function (anonymous)]"
318→
319→
320→class JSRegExp(JSObject):
321→ """JavaScript RegExp object."""
322→
323→ def __init__(self, pattern: str, flags: str = "", poll_callback=None):
324→ super().__init__()
325→ from .regex import RegExp as InternalRegExp, MatchResult
326→
327→ self._internal = InternalRegExp(pattern, flags, poll_callback)
328→ self._pattern = pattern
329→ self._flags = flags
330→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see - JSFunction doesn't have a _prototype attribute. I need to set it up when the function is created. In JavaScript, every function has a prototype property that is an object with a constructor property pointing back to the function.Let me search for where functions are created in the VM.
{
"-A": 30,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "OpCode.MAKE_FUNCTION"
}{
"-A": 30,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "LOAD_FUNC"
}{
"-A": 10,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "CLOSURE"
}155: OpCode.LOAD_CLOSURE, OpCode.STORE_CLOSURE,
156- OpCode.LOAD_CELL, OpCode.STORE_CELL,
157- OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
158- OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
159: OpCode.MAKE_CLOSURE,
160- ):
161- arg = bytecode[frame.ip]
162- frame.ip += 1
163-
164- # Execute opcode
165- self._execute_opcode(op, arg, frame)
166-
167- # Check if frame was popped (return)
168- if not self.call_stack:
169- break
--
246: elif op == OpCode.LOAD_CLOSURE:
247- if frame.closure_cells and arg < len(frame.closure_cells):
248- self.stack.append(frame.closure_cells[arg].value)
249- else:
250- raise JSReferenceError("Closure variable not found")
251-
252: elif op == OpCode.STORE_CLOSURE:
253- if frame.closure_cells and arg < len(frame.closure_cells):
254- frame.closure_cells[arg].value = self.stack[-1]
255- else:
256- raise JSReferenceError("Closure variable not found")
257-
258- elif op == OpCode.LOAD_CELL:
259- if frame.cell_storage and arg < len(frame.cell_storage):
260- self.stack.append(frame.cell_storage[arg].value)
261- else:
262- raise JSReferenceError("Cell variable not found")
--
649: elif op == OpCode.MAKE_CLOSURE:
650- compiled_func = self.stack.pop()
651- if isinstance(compiled_func, CompiledFunction):
652- js_func = JSFunction(
653- name=compiled_func.name,
654- params=compiled_func.params,
655- bytecode=compiled_func.bytecode,
656- )
657- js_func._compiled = compiled_func
658-
659- # Capture closure cells for free variables
--
1578: OpCode.LOAD_CLOSURE, OpCode.STORE_CLOSURE,
1579- OpCode.LOAD_CELL, OpCode.STORE_CELL,
1580- OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
1581- OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
1582: OpCode.MAKE_CLOSURE,
1583- ):
1584- arg = bytecode[frame.ip]
1585- frame.ip += 1
1586-
1587- self._execute_opcode(op, arg, frame)
1588-
1589- # Get result from stack
1590- if len(self.stack) > stack_len:
1591- return self.stack.pop()
1592- return UNDEFINEDI found it - MAKE_CLOSURE is where functions are created. Let me look at the full implementation.
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 35,
"offset": 649
}649→ elif op == OpCode.MAKE_CLOSURE: 650→ compiled_func = self.stack.pop() 651→ if isinstance(compiled_func, CompiledFunction): 652→ js_func = JSFunction( 653→ name=compiled_func.name, 654→ params=compiled_func.params, 655→ bytecode=compiled_func.bytecode, 656→ ) 657→ js_func._compiled = compiled_func 658→ 659→ # Capture closure cells for free variables 660→ if compiled_func.free_vars: 661→ closure_cells = [] 662→ for var_name in compiled_func.free_vars: 663→ # First check if it's in our cell_storage (cell var) 664→ if frame.cell_storage and var_name in getattr(frame.func, 'cell_vars', []): 665→ idx = frame.func.cell_vars.index(var_name) 666→ # Share the same cell! 667→ closure_cells.append(frame.cell_storage[idx]) 668→ elif frame.closure_cells and var_name in getattr(frame.func, 'free_vars', []): 669→ # Variable is in our own closure 670→ idx = frame.func.free_vars.index(var_name) 671→ closure_cells.append(frame.closure_cells[idx]) 672→ elif var_name in frame.func.locals: 673→ # Regular local - shouldn't happen if cell_vars is working 674→ slot = frame.func.locals.index(var_name) 675→ cell = ClosureCell(frame.locals[slot]) 676→ closure_cells.append(cell) 677→ else: 678→ closure_cells.append(ClosureCell(UNDEFINED)) 679→ js_func._closure_cells = closure_cells 680→ 681→ self.stack.append(js_func) 682→ else: 683→ self.stack.append(compiled_func) <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
I need to add a _prototype property to the JSFunction when it's created. The prototype should be an object with a constructor property pointing back to the function.
elif op == OpCode.MAKE_CLOSURE:
compiled_func = self.stack.pop()
if isinstance(compiled_func, CompiledFunction):
js_func = JSFunction(
name=compiled_func.name,
params=compiled_func.params,
bytecode=compiled_func.bytecode,
)
js_func._compiled = compiled_func
# Capture closure cells for free variables
if compiled_func.free_vars:
closure_cells = []
for var_name in compiled_func.free_vars:
# First check if it's in our cell_storage (cell var)
if frame.cell_storage and var_name in getattr(frame.func, 'cell_vars', []):
idx = frame.func.cell_vars.index(var_name)
# Share the same cell!
closure_cells.append(frame.cell_storage[idx])
elif frame.closure_cells and var_name in getattr(frame.func, 'free_vars', []):
# Variable is in our own closure
idx = frame.func.free_vars.index(var_name)
closure_cells.append(frame.closure_cells[idx])
elif var_name in frame.func.locals:
# Regular local - shouldn't happen if cell_vars is working
slot = frame.func.locals.index(var_name)
cell = ClosureCell(frame.locals[slot])
closure_cells.append(cell)
else:
closure_cells.append(ClosureCell(UNDEFINED))
js_func._closure_cells = closure_cells
self.stack.append(js_func)
else:
self.stack.append(compiled_func) elif op == OpCode.MAKE_CLOSURE:
compiled_func = self.stack.pop()
if isinstance(compiled_func, CompiledFunction):
js_func = JSFunction(
name=compiled_func.name,
params=compiled_func.params,
bytecode=compiled_func.bytecode,
)
js_func._compiled = compiled_func
# Create prototype object for the function
# In JavaScript, every function has a prototype property
prototype = JSObject()
prototype.set("constructor", js_func)
js_func._prototype = prototype
# Capture closure cells for free variables
if compiled_func.free_vars:
closure_cells = []
for var_name in compiled_func.free_vars:
# First check if it's in our cell_storage (cell var)
if frame.cell_storage and var_name in getattr(frame.func, 'cell_vars', []):
idx = frame.func.cell_vars.index(var_name)
# Share the same cell!
closure_cells.append(frame.cell_storage[idx])
elif frame.closure_cells and var_name in getattr(frame.func, 'free_vars', []):
# Variable is in our own closure
idx = frame.func.free_vars.index(var_name)
closure_cells.append(frame.closure_cells[idx])
elif var_name in frame.func.locals:
# Regular local - shouldn't happen if cell_vars is working
slot = frame.func.locals.index(var_name)
cell = ClosureCell(frame.locals[slot])
closure_cells.append(cell)
else:
closure_cells.append(ClosureCell(UNDEFINED))
js_func._closure_cells = closure_cells
self.stack.append(js_func)
else:
self.stack.append(compiled_func)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
645→ a = self.stack.pop()
646→ self.stack.append(to_number(a) - 1)
647→
648→ # Closures
649→ elif op == OpCode.MAKE_CLOSURE:
650→ compiled_func = self.stack.pop()
651→ if isinstance(compiled_func, CompiledFunction):
652→ js_func = JSFunction(
653→ name=compiled_func.name,
654→ params=compiled_func.params,
655→ bytecode=compiled_func.bytecode,
656→ )
657→ js_func._compiled = compiled_func
658→
659→ # Create prototype object for the function
660→ # In JavaScript, every function has a prototype property
661→ prototype = JSObject()
662→ prototype.set("constructor", js_func)
663→ js_func._prototype = prototype
664→
665→ # Capture closure cells for free variables
666→ if compiled_func.free_vars:
667→ closure_cells = []
668→ for var_name in compiled_func.free_vars:
669→ # First check if it's in our cell_storage (cell var)
670→ if frame.cell_storage and var_name in getattr(frame.func, 'cell_vars', []):
671→ idx = frame.func.cell_vars.index(var_name)
672→ # Share the same cell!
673→ closure_cells.append(frame.cell_storage[idx])
674→ elif frame.closure_cells and var_name in getattr(frame.func, 'free_vars', []):
675→ # Variable is in our own closure
676→ idx = frame.func.free_vars.index(var_name)
677→ closure_cells.append(frame.closure_cells[idx])
678→ elif var_name in frame.func.locals:
679→ # Regular local - shouldn't happen if cell_vars is working
680→ slot = frame.func.locals.index(var_name)
681→ cell = ClosureCell(frame.locals[slot])
682→ closure_cells.append(cell)
683→ else:
684→ closure_cells.append(ClosureCell(UNDEFINED))
685→ js_func._closure_cells = closure_cells
686→
687→ self.stack.append(js_func)
688→ else:
689→ self.stack.append(compiled_func)
690→
691→ else:
692→ raise NotImplementedError(f"Opcode not implemented: {op.name}")
693→uv run python << 'PYTHON'
from mquickjs_python import JSContext
ctx = JSContext()
result = ctx.eval('''
function F(x) {
this.x = x;
}
var b = new F(2);
b instanceof F
''')
print(f"Result: {result}")
PYTHON
.. [ 42%] tests/test_parser.py ................................................... [ 54%] ........ [ 56%] tests/test_regex.py .................................................... [ 69%] .................................... [ 78%] tests/test_string_regex.py ................... [ 83%] tests/test_vm.py ....................................................... [ 97%] .......... [100%] ======================== 394 passed, 5 xfailed in 4.67s ========================
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval(open('tests/test_language.js').read())
print('SUCCESS')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1FAILED: JSError: Error: assertion failed: got boolean:|false|, expected boolean:|true| (instanceof Object)
The issue is instanceof Object. An object created with new Object() or {} should be an instance of Object. The issue is that regular objects don't have the Object prototype chain set up. Let me also check for built-in constructors.
uv run python << 'PYTHON'
from mquickjs_python import JSContext
ctx = JSContext()
# Test instanceof Object
tests = [
('({}) instanceof Object', True),
('[] instanceof Array', True),
('(new Object()) instanceof Object', True),
]
for expr, expected in tests:
result = ctx.eval(expr)
if result != expected:
print(f'FAIL: {expr} = {result}, expected {expected}')
else:
print(f'PASS: {expr} = {result}')
PYTHON
FAIL: ({}) instanceof Object = False, expected True
FAIL: [] instanceof Array = False, expected True
FAIL: (new Object()) instanceof Object = False, expected TrueI see - regular objects created with {} and new Object() don't have the proper prototype chain set up. I need to:1. Set up Object.prototype as the prototype for all plain objects2. Set up Array.prototype as the prototype for all arrays3. Also set up the _prototype for Object and Array constructorsThis is getting complex. Let me think about this more carefully.
In JavaScript:- Every object has a [[Prototype]] (internal slot, accessed via __proto__ or Object.getPrototypeOf)- Object.prototype is the base of all prototypes- Array.prototype inherits from Object.prototype- When you do new Object(), the result has Object.prototype as its prototype
- When you do {}, the result also has Object.prototype as its prototype
I need to:1. Create Object.prototype and set it as the base2. Make all JSObjects have Object.prototype as their _prototype by default3. Create Array.prototype (which inherits from Object.prototype)
4. Make all JSArrays have Array.prototype as their _prototype5. When doing instanceof Object, check if the object's prototype chain includes Object.prototype
Let me simplify this for now - I'll set up the prototype chains properly in the context initialization.
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"limit": 30,
"offset": 83
} 83→ def _create_object_constructor(self) -> JSCallableObject:
84→ """Create the Object constructor with static methods."""
85→ # Constructor function - new Object() creates empty object
86→ def object_constructor(*args):
87→ return JSObject()
88→
89→ # Create a callable object that acts as constructor
90→ obj_constructor = JSCallableObject(object_constructor)
91→
92→ def keys_fn(*args):
93→ obj = args[0] if args else UNDEFINED
94→ if not isinstance(obj, JSObject):
95→ return JSArray()
96→ arr = JSArray()
97→ arr._elements = list(obj.keys())
98→ return arr
99→
100→ def values_fn(*args):
101→ obj = args[0] if args else UNDEFINED
102→ if not isinstance(obj, JSObject):
103→ return JSArray()
104→ arr = JSArray()
105→ arr._elements = [obj.get(k) for k in obj.keys()]
106→ return arr
107→
108→ def entries_fn(*args):
109→ obj = args[0] if args else UNDEFINED
110→ if not isinstance(obj, JSObject):
111→ return JSArray()
112→ arr = JSArray()
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
This is getting complex. Let me take a simpler approach. I'll update the Object and Array constructors to have a proper _prototype attribute, and update the VM to set the prototype of new objects.First, let me update the Object constructor to have a prototype:
def _create_object_constructor(self) -> JSCallableObject:
"""Create the Object constructor with static methods."""
# Constructor function - new Object() creates empty object
def object_constructor(*args):
return JSObject()
# Create a callable object that acts as constructor
obj_constructor = JSCallableObject(object_constructor) def _create_object_constructor(self) -> JSCallableObject:
"""Create the Object constructor with static methods."""
# Create Object.prototype first
object_prototype = JSObject()
# Constructor function - new Object() creates empty object
def object_constructor(*args):
obj = JSObject()
obj._prototype = object_prototype
return obj
# Create a callable object that acts as constructor
obj_constructor = JSCallableObject(object_constructor)
obj_constructor._prototype = object_prototype
object_prototype.set("constructor", obj_constructor)
# Store for other constructors to use
self._object_prototype = object_prototypeThe file /home/user/mquickjs-python/src/mquickjs_python/context.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
79→ def _console_log(self, *args: JSValue) -> None:
80→ """Console.log implementation."""
81→ print(" ".join(to_string(arg) for arg in args))
82→
83→ def _create_object_constructor(self) -> JSCallableObject:
84→ """Create the Object constructor with static methods."""
85→ # Create Object.prototype first
86→ object_prototype = JSObject()
87→
88→ # Constructor function - new Object() creates empty object
89→ def object_constructor(*args):
90→ obj = JSObject()
91→ obj._prototype = object_prototype
92→ return obj
93→
94→ # Create a callable object that acts as constructor
95→ obj_constructor = JSCallableObject(object_constructor)
96→ obj_constructor._prototype = object_prototype
97→ object_prototype.set("constructor", obj_constructor)
98→
99→ # Store for other constructors to use
100→ self._object_prototype = object_prototype
101→
102→ def keys_fn(*args):
103→ obj = args[0] if args else UNDEFINED
104→ if not isinstance(obj, JSObject):Now I need to update the Array constructor to inherit from Object.prototype, and update the VM to set the prototype for objects created with {} and arrays created with [].
First, let me update the Array constructor:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"limit": 25,
"offset": 145
} 145→ obj_constructor.set("entries", entries_fn)
146→ obj_constructor.set("assign", assign_fn)
147→
148→ return obj_constructor
149→
150→ def _create_array_constructor(self) -> JSCallableObject:
151→ """Create the Array constructor with static methods."""
152→ def array_constructor(*args):
153→ if len(args) == 1 and isinstance(args[0], (int, float)):
154→ return JSArray(int(args[0]))
155→ arr = JSArray()
156→ for arg in args:
157→ arr.push(arg)
158→ return arr
159→
160→ arr_constructor = JSCallableObject(array_constructor)
161→
162→ # Array.isArray()
163→ def is_array(*args):
164→ obj = args[0] if args else UNDEFINED
165→ return isinstance(obj, JSArray)
166→
167→ arr_constructor.set("isArray", is_array)
168→
169→ return arr_constructor
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I need to also update Array constructor. But I also need to check if _object_prototype is set first, so I need to ensure the order of constructor creation is correct.Let me update the __init__ to set up Object first, then Array.
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"limit": 40,
"offset": 40
} 40→ self._globals["console"] = console
41→
42→ # Infinity and NaN
43→ self._globals["Infinity"] = float("inf")
44→ self._globals["NaN"] = float("nan")
45→ self._globals["undefined"] = UNDEFINED
46→
47→ # Basic type constructors (minimal implementations)
48→ self._globals["Object"] = self._create_object_constructor()
49→ self._globals["Array"] = self._create_array_constructor()
50→ self._globals["Error"] = self._error_constructor
51→
52→ # Math object
53→ self._globals["Math"] = self._create_math_object()
54→
55→ # JSON object
56→ self._globals["JSON"] = self._create_json_object()
57→
58→ # Number constructor and methods
59→ self._globals["Number"] = self._create_number_constructor()
60→
61→ # String constructor and methods
62→ self._globals["String"] = self._create_string_constructor()
63→
64→ # Boolean constructor
65→ self._globals["Boolean"] = self._create_boolean_constructor()
66→
67→ # Date constructor
68→ self._globals["Date"] = self._create_date_constructor()
69→
70→ # RegExp constructor
71→ self._globals["RegExp"] = self._create_regexp_constructor()
72→
73→ # Global number functions
74→ self._globals["isNaN"] = self._global_isnan
75→ self._globals["isFinite"] = self._global_isfinite
76→ self._globals["parseInt"] = self._global_parseint
77→ self._globals["parseFloat"] = self._global_parsefloat
78→
79→ def _console_log(self, *args: JSValue) -> None:
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
Good, Object is created before Array. Now let me update Array constructor to use Object.prototype.
def _create_array_constructor(self) -> JSCallableObject:
"""Create the Array constructor with static methods."""
def array_constructor(*args):
if len(args) == 1 and isinstance(args[0], (int, float)):
return JSArray(int(args[0]))
arr = JSArray()
for arg in args:
arr.push(arg)
return arr
arr_constructor = JSCallableObject(array_constructor)
# Array.isArray()
def is_array(*args):
obj = args[0] if args else UNDEFINED
return isinstance(obj, JSArray)
arr_constructor.set("isArray", is_array)
return arr_constructor def _create_array_constructor(self) -> JSCallableObject:
"""Create the Array constructor with static methods."""
# Create Array.prototype (inherits from Object.prototype)
array_prototype = JSArray()
array_prototype._prototype = self._object_prototype
def array_constructor(*args):
if len(args) == 1 and isinstance(args[0], (int, float)):
arr = JSArray(int(args[0]))
else:
arr = JSArray()
for arg in args:
arr.push(arg)
arr._prototype = array_prototype
return arr
arr_constructor = JSCallableObject(array_constructor)
arr_constructor._prototype = array_prototype
array_prototype.set("constructor", arr_constructor)
# Store for other uses
self._array_prototype = array_prototype
# Array.isArray()
def is_array(*args):
obj = args[0] if args else UNDEFINED
return isinstance(obj, JSArray)
arr_constructor.set("isArray", is_array)
return arr_constructorThe file /home/user/mquickjs-python/src/mquickjs_python/context.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
146→ obj_constructor.set("assign", assign_fn)
147→
148→ return obj_constructor
149→
150→ def _create_array_constructor(self) -> JSCallableObject:
151→ """Create the Array constructor with static methods."""
152→ # Create Array.prototype (inherits from Object.prototype)
153→ array_prototype = JSArray()
154→ array_prototype._prototype = self._object_prototype
155→
156→ def array_constructor(*args):
157→ if len(args) == 1 and isinstance(args[0], (int, float)):
158→ arr = JSArray(int(args[0]))
159→ else:
160→ arr = JSArray()
161→ for arg in args:
162→ arr.push(arg)
163→ arr._prototype = array_prototype
164→ return arr
165→
166→ arr_constructor = JSCallableObject(array_constructor)
167→ arr_constructor._prototype = array_prototype
168→ array_prototype.set("constructor", arr_constructor)
169→
170→ # Store for other uses
171→ self._array_prototype = array_prototype
172→
173→ # Array.isArray()
174→ def is_array(*args):
175→ obj = args[0] if args else UNDEFINED
176→ return isinstance(obj, JSArray)
177→
178→ arr_constructor.set("isArray", is_array)
179→
180→ return arr_constructor
181→
182→ def _error_constructor(self, message: JSValue = UNDEFINED) -> JSObject:
183→ """Error constructor."""
184→ err = JSObject()Now I need to update the VM to set up prototypes for objects created with {} and arrays created with []. The VM has access to the context's globals, so I can get the Object and Array constructors from there.Let me check how BUILD_OBJECT and BUILD_ARRAY work.
{
"-A": 20,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "OpCode.BUILD_OBJECT"
}158: OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
159- OpCode.MAKE_CLOSURE,
160- ):
161- arg = bytecode[frame.ip]
162- frame.ip += 1
163-
164- # Execute opcode
165- self._execute_opcode(op, arg, frame)
166-
167- # Check if frame was popped (return)
168- if not self.call_stack:
169- break
170-
171- return self.stack.pop() if self.stack else UNDEFINED
172-
173- def _execute_opcode(self, op: OpCode, arg: Optional[int], frame: CallFrame) -> None:
174- """Execute a single opcode."""
175-
176- # Stack operations
177- if op == OpCode.POP:
178- if self.stack:
--
298: elif op == OpCode.BUILD_OBJECT:
299- obj = JSObject()
300- props = []
301- for _ in range(arg):
302- value = self.stack.pop()
303- kind = self.stack.pop()
304- key = self.stack.pop()
305- props.insert(0, (key, kind, value))
306- for key, kind, value in props:
307- key_str = to_string(key) if not isinstance(key, str) else key
308- if kind == "get":
309- obj.define_getter(key_str, value)
310- elif kind == "set":
311- obj.define_setter(key_str, value)
312- else:
313- obj.set(key_str, value)
314- self.stack.append(obj)
315-
316- elif op == OpCode.BUILD_REGEX:
317- pattern, flags = frame.func.constants[arg]
318- regex = JSRegExp(pattern, flags)
--
1587: OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
1588- OpCode.MAKE_CLOSURE,
1589- ):
1590- arg = bytecode[frame.ip]
1591- frame.ip += 1
1592-
1593- self._execute_opcode(op, arg, frame)
1594-
1595- # Get result from stack
1596- if len(self.stack) > stack_len:
1597- return self.stack.pop()
1598- return UNDEFINED
1599- elif callable(callback):
1600- result = callback(*args)
1601- return result if result is not None else UNDEFINED
1602- else:
1603- raise JSTypeError(f"{callback} is not a function")
1604-
1605- def _invoke_js_function(
1606- self,
1607- func: JSFunction,I need to update BUILD_OBJECT and BUILD_ARRAY to set the prototype. However, the VM doesn't have direct access to the context's prototypes.I need to pass these prototypes to the VM somehow. Let me check how the VM is initialized.
{
"-A": 15,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "class VM"
}71:class VM:
72- """JavaScript virtual machine."""
73-
74- def __init__(
75- self,
76- memory_limit: Optional[int] = None,
77- time_limit: Optional[float] = None,
78- ):
79- self.memory_limit = memory_limit
80- self.time_limit = time_limit
81-
82- self.stack: List[JSValue] = []
83- self.call_stack: List[CallFrame] = []
84- self.globals: Dict[str, JSValue] = {}
85-
86- self.start_time: Optional[float] = NoneI see that the VM has a globals dictionary. I can access the Object and Array constructors from there. Let me update BUILD_OBJECT and BUILD_ARRAY to use the prototype from the constructor.
elif op == OpCode.BUILD_OBJECT:
obj = JSObject()
props = []
for _ in range(arg):
value = self.stack.pop()
kind = self.stack.pop()
key = self.stack.pop()
props.insert(0, (key, kind, value))
for key, kind, value in props:
key_str = to_string(key) if not isinstance(key, str) else key
if kind == "get":
obj.define_getter(key_str, value)
elif kind == "set":
obj.define_setter(key_str, value)
else:
obj.set(key_str, value)
self.stack.append(obj) elif op == OpCode.BUILD_OBJECT:
obj = JSObject()
# Set prototype from Object constructor
object_constructor = self.globals.get("Object")
if object_constructor and hasattr(object_constructor, '_prototype'):
obj._prototype = object_constructor._prototype
props = []
for _ in range(arg):
value = self.stack.pop()
kind = self.stack.pop()
key = self.stack.pop()
props.insert(0, (key, kind, value))
for key, kind, value in props:
key_str = to_string(key) if not isinstance(key, str) else key
if kind == "get":
obj.define_getter(key_str, value)
elif kind == "set":
obj.define_setter(key_str, value)
else:
obj.set(key_str, value)
self.stack.append(obj)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
294→ arr = JSArray()
295→ arr._elements = elements
296→ self.stack.append(arr)
297→
298→ elif op == OpCode.BUILD_OBJECT:
299→ obj = JSObject()
300→ # Set prototype from Object constructor
301→ object_constructor = self.globals.get("Object")
302→ if object_constructor and hasattr(object_constructor, '_prototype'):
303→ obj._prototype = object_constructor._prototype
304→ props = []
305→ for _ in range(arg):
306→ value = self.stack.pop()
307→ kind = self.stack.pop()
308→ key = self.stack.pop()
309→ props.insert(0, (key, kind, value))
310→ for key, kind, value in props:
311→ key_str = to_string(key) if not isinstance(key, str) else key
312→ if kind == "get":
313→ obj.define_getter(key_str, value)
314→ elif kind == "set":
315→ obj.define_setter(key_str, value)
316→ else:
317→ obj.set(key_str, value)
318→ self.stack.append(obj)
319→
320→ elif op == OpCode.BUILD_REGEX:
321→ pattern, flags = frame.func.constants[arg]
322→ regex = JSRegExp(pattern, flags) elif op == OpCode.BUILD_ARRAY:
elements = []
for _ in range(arg):
elements.insert(0, self.stack.pop())
arr = JSArray()
arr._elements = elements
self.stack.append(arr) elif op == OpCode.BUILD_ARRAY:
elements = []
for _ in range(arg):
elements.insert(0, self.stack.pop())
arr = JSArray()
arr._elements = elements
# Set prototype from Array constructor
array_constructor = self.globals.get("Array")
if array_constructor and hasattr(array_constructor, '_prototype'):
arr._prototype = array_constructor._prototype
self.stack.append(arr)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
286→ result = self._delete_property(obj, key)
287→ self.stack.append(result)
288→
289→ # Arrays/Objects
290→ elif op == OpCode.BUILD_ARRAY:
291→ elements = []
292→ for _ in range(arg):
293→ elements.insert(0, self.stack.pop())
294→ arr = JSArray()
295→ arr._elements = elements
296→ # Set prototype from Array constructor
297→ array_constructor = self.globals.get("Array")
298→ if array_constructor and hasattr(array_constructor, '_prototype'):
299→ arr._prototype = array_constructor._prototype
300→ self.stack.append(arr)
301→
302→ elif op == OpCode.BUILD_OBJECT:
303→ obj = JSObject()
304→ # Set prototype from Object constructoruv run python << 'PYTHON'
from mquickjs_python import JSContext
ctx = JSContext()
# Test instanceof Object
tests = [
('({}) instanceof Object', True),
('[] instanceof Array', True),
('(new Object()) instanceof Object', True),
]
for expr, expected in tests:
result = ctx.eval(expr)
if result != expected:
print(f'FAIL: {expr} = {result}, expected {expected}')
else:
print(f'PASS: {expr} = {result}')
PYTHON
PASS: ({}) instanceof Object = True
PASS: [] instanceof Array = True
PASS: (new Object()) instanceof Object = True.. [ 42%] tests/test_parser.py ................................................... [ 54%] ........ [ 56%] tests/test_regex.py .................................................... [ 69%] .................................... [ 78%] tests/test_string_regex.py ................... [ 83%] tests/test_vm.py ....................................................... [ 97%] .......... [100%] ======================== 394 passed, 5 xfailed in 4.67s ========================
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval(open('tests/test_language.js').read())
print('SUCCESS')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1FAILED: JSError: Error: assertion failed: got string:|object|, expected string:|function| (typeof)
Now we have an error about typeof. The assertion expects function but gets object. Let me see where this happens in the test.
The test is checking typeof Object, which should be "function" since Object is a constructor. Let me check how typeof is implemented for JSCallableObject.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
result = ctx.eval('typeof Object')
print(f'typeof Object = {result}')
"The result is "object" but it should be "function". Let me check how js_typeof handles JSCallableObject.
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/values.py",
"limit": 20,
"offset": 80
} 80→ """Return the JavaScript typeof for a value."""
81→ if value is UNDEFINED:
82→ return "undefined"
83→ if value is NULL:
84→ return "object" # JavaScript quirk
85→ if isinstance(value, bool):
86→ return "boolean"
87→ if isinstance(value, (int, float)):
88→ return "number"
89→ if isinstance(value, str):
90→ return "string"
91→ if isinstance(value, JSFunction):
92→ return "function"
93→ if isinstance(value, JSObject):
94→ return "object"
95→ return "undefined"
96→
97→
98→def to_boolean(value: JSValue) -> bool:
99→ """Convert a JavaScript value to boolean."""
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see - js_typeof checks for JSFunction first, then JSObject. But JSCallableObject is a subclass of JSObject and has a _call_fn, so it should be considered a function. Let me check the class hierarchy.
{
"-A": 10,
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/values.py",
"pattern": "class JSCallableObject"
}239:class JSCallableObject(JSObject): 240- """JavaScript object that is also callable (for constructors like Number, String, Boolean).""" 241- 242- def __init__(self, call_fn, prototype: Optional["JSObject"] = None): 243- super().__init__(prototype) 244- self._call_fn = call_fn 245- 246- def __call__(self, *args): 247- return self._call_fn(*args) 248- 249- def __repr__(self) -> str:
"""Return the JavaScript typeof for a value."""
if value is UNDEFINED:
return "undefined"
if value is NULL:
return "object" # JavaScript quirk
if isinstance(value, bool):
return "boolean"
if isinstance(value, (int, float)):
return "number"
if isinstance(value, str):
return "string"
if isinstance(value, JSFunction):
return "function"
if isinstance(value, JSObject):
return "object"
return "undefined" """Return the JavaScript typeof for a value."""
if value is UNDEFINED:
return "undefined"
if value is NULL:
return "object" # JavaScript quirk
if isinstance(value, bool):
return "boolean"
if isinstance(value, (int, float)):
return "number"
if isinstance(value, str):
return "string"
if isinstance(value, JSFunction):
return "function"
# JSCallableObject (like Object, Array constructors) should be "function"
if isinstance(value, JSObject) and hasattr(value, '_call_fn'):
return "function"
if isinstance(value, JSObject):
return "object"
return "undefined"The file /home/user/mquickjs-python/src/mquickjs_python/values.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
76→ return isinstance(value, float) and math.isinf(value)
77→
78→
79→def js_typeof(value: JSValue) -> str:
80→ """Return the JavaScript typeof for a value."""
81→ if value is UNDEFINED:
82→ return "undefined"
83→ if value is NULL:
84→ return "object" # JavaScript quirk
85→ if isinstance(value, bool):
86→ return "boolean"
87→ if isinstance(value, (int, float)):
88→ return "number"
89→ if isinstance(value, str):
90→ return "string"
91→ if isinstance(value, JSFunction):
92→ return "function"
93→ # JSCallableObject (like Object, Array constructors) should be "function"
94→ if isinstance(value, JSObject) and hasattr(value, '_call_fn'):
95→ return "function"
96→ if isinstance(value, JSObject):
97→ return "object"
98→ return "undefined"
99→
100→
101→def to_boolean(value: JSValue) -> bool:
102→ """Convert a JavaScript value to boolean."""uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
result = ctx.eval('typeof Object')
print(f'typeof Object = {result}')
assert result == 'function'
print('OK')
".. [ 42%] tests/test_parser.py ................................................... [ 54%] ........ [ 56%] tests/test_regex.py .................................................... [ 69%] .................................... [ 78%] tests/test_string_regex.py ................... [ 83%] tests/test_vm.py ....................................................... [ 97%] .......... [100%] ======================== 394 passed, 5 xfailed in 4.64s ========================
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
try:
ctx.eval(open('tests/test_language.js').read())
print('SUCCESS')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1This session is being continued from a previous conversation that ran out of context. The conversation is summarized below: Analysis: Let me analyze the conversation chronologically:
Initial Context: This is a continuation of a previous session about mquickjs-python (a pure Python JavaScript engine). The user's main directive was "Finish it, TDD, commit often" - implementing all remaining features using Test-Driven Development.
Starting State: The todo list showed completed items (labeled statements, Object/Array/Function constructors) and many pending items.
Work Done in This Session:
a. Built-in constructors (Object/Array/RegExp):
- Changed _create_object_constructor to use JSCallableObject
- Changed _create_array_constructor to use JSCallableObject
- Updated RegExp constructor to use JSCallableObject
- VM now checks for _call_fn attribute
b. ASI (Automatic Semicolon Insertion) for break/continue:
- Issue: break followed by identifier on new line was consuming identifier as label
- Fix: Check if identifier is on same line as break/continue before treating as label
- Added tests in TestASI class
c. Member expression update (a.x++, arr[i]--): - Added DUP2 and ROT4 opcodes - Implemented prefix and postfix update expressions on member expressions - Complex stack manipulation for correct value return
d. Signed 32-bit left shift:
- Issue: 1 << 31 returning positive number instead of -2147483648
- Fix: Convert SHL result back to signed 32-bit
e. Negative zero handling: - Division by negative zero now returns correct sign - NEG operation produces -0.0 when negating positive zero - MUL uses floats for proper -0.0 handling
f. Constructor calls (new F(x)): - Added is_constructor_call and new_target to CallFrame - Updated RETURN/RETURN_UNDEFINED to check for constructor calls - Constructor now properly returns the new object
g. instanceof operator: - Added prototype property to functions when created with MAKE_CLOSURE - Updated instanceof to check prototype chain - Set up prototype chains for Object and Array constructors - Updated BUILD_OBJECT and BUILD_ARRAY to set prototypes
h. typeof for callable objects: - Updated js_typeof to return "function" for objects with _call_fn
Current Error: test_language.js fails with "unknown_var is not defined" - this is about typeof unknown_var which should return "undefined" for undeclared variables, not throw an error.
User Messages:
Summary:
1. Primary Request and Intent:
The user wants to complete the mquickjs-python JavaScript engine implementation using TDD (Test-Driven Development) approach, committing frequently. The main goal is to make the xfailed JavaScript tests pass, especially test_language.js, test_builtin.js, and others from the original mquickjs C implementation. User emphasized: "Finish it, TDD, commit often" and "Do the rest while I sleep".
new operator semanticsCallFrame with constructor call tracking
Files and Code Sections:
src/mquickjs_python/vm.py:
python
@dataclass
class CallFrame:
# ... existing fields ...
is_constructor_call: bool = False # True if this frame is from a "new" call
new_target: JSValue = None # The new object for constructor callssrc/mquickjs_python/parser.py:
python
def _parse_break_statement(self) -> BreakStatement:
label = None
# Only consume identifier as label if on same line (ASI rule)
if self._check(TokenType.IDENTIFIER) and self.current.line == self.previous.line:
label = Identifier(self._advance().value)
self._consume_semicolon()
return BreakStatement(label)src/mquickjs_python/context.py:
src/mquickjs_python/values.py:
python
if isinstance(value, JSObject) and hasattr(value, '_call_fn'):
return "function"src/mquickjs_python/opcodes.py:
tests/test_vm.py:
Errors and fixes:
ASI issue with break/continue: while (1) label: break followed by i++ on new line caused parse error
self.current.line == self.previous.line before consuming identifier as labelSHL returning unsigned: 1 << 31 returned 2147483648 instead of -2147483648
Negative zero division: 1/(-0.0) returned Infinity instead of -Infinity
math.copysign(1, b_num) to detect zero sign in DIVConstructor not returning object: new F(2) returned undefined
instanceof not working: b instanceof F returned False
typeof Object returning "object": Should be "function"
_call_fn attribute in js_typeofProblem Solving:
Current issue: typeof unknown_var throws error instead of returning "undefined"
All user messages:
"Do the rest while I sleep"
Pending Tasks (from todo list):
Add eval() function
Current Work:
Working through test_language.js to make it pass. The current error is:
FAILED: JSReferenceError: ReferenceError: unknown_var is not defined
This is from line 262 of test_language.js:
javascript
assert((typeof unknown_var), "undefined", "typeof");
In JavaScript, typeof on an undeclared variable should return "undefined" without throwing an error. The current implementation throws a ReferenceError instead.
Optional Next Step:
Fix the typeof operator to handle undeclared variables. Currently typeof unknown_var throws a ReferenceError, but it should return "undefined". This requires modifying how TYPEOF opcode handles LOAD_NAME that fails to find the variable. The exact error is:
FAILED: JSReferenceError: ReferenceError: unknown_var is not defined
From test: assert((typeof unknown_var), "undefined", "typeof");.
Please continue the conversation from where we left it off without asking the user any further questions. Continue with the last task that you were asked to work on.
Looking at the summary, I need to continue working on making the xfailed JavaScript tests pass. The current issue is that typeof unknown_var throws a ReferenceError instead of returning "undefined".
In JavaScript, typeof is special - it's the only operator that can be used on undeclared variables without throwing a ReferenceError. It should return "undefined" for undeclared variables.
The current implementation likely compiles typeof unknown_var to:
1. LOAD_NAME "unknown_var" - this throws if variable doesn't exist
2. TYPEOF
But it should handle this specially. Let me look at how this is compiled and executed.
I need to:
1. Read the compiler.py to see how typeof is compiled
2. Read the vm.py to see how TYPEOF is executed
3. Implement a special case for typeof <identifier> that doesn't throw
One common approach is: - Add a special opcode like TYPEOF_NAME that does both the lookup and typeof in one, returning "undefined" if the variable doesn't exist - Or modify the compiler to emit a different sequence for typeof with identifier operand
Let me read the current implementation first.
I need to fix typeof unknown_var to return "undefined" instead of throwing a ReferenceError. In JavaScript, typeof is special - it's the only operator that can safely be used on undeclared variables.
Let me first check how typeof is currently compiled and executed:
{
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python",
"pattern": "TYPEOF"
} 1→"""Bytecode opcodes for the JavaScript VM."""
2→
3→from enum import IntEnum, auto
4→
5→
6→class OpCode(IntEnum):
7→ """Bytecode operation codes."""
8→
9→ # Stack operations
10→ POP = auto() # Pop and discard top of stack
11→ DUP = auto() # Duplicate top of stack
12→ DUP2 = auto() # Duplicate top two stack items: a, b -> a, b, a, b
13→ SWAP = auto() # Swap top two stack items
14→ ROT3 = auto() # Rotate 3 items: a, b, c -> b, c, a
15→ ROT4 = auto() # Rotate 4 items: a, b, c, d -> b, c, d, a
16→
17→ # Constants
18→ LOAD_CONST = auto() # Load constant from pool: arg = constant index
19→ LOAD_UNDEFINED = auto()
20→ LOAD_NULL = auto()
21→ LOAD_TRUE = auto()
22→ LOAD_FALSE = auto()
23→
24→ # Variables
25→ LOAD_NAME = auto() # Load variable by name: arg = name index
26→ STORE_NAME = auto() # Store variable by name: arg = name index
27→ LOAD_LOCAL = auto() # Load local variable: arg = slot index
28→ STORE_LOCAL = auto() # Store local variable: arg = slot index
29→
30→ # Properties
31→ GET_PROP = auto() # Get property: obj, key -> value
32→ SET_PROP = auto() # Set property: obj, key, value -> value
33→ DELETE_PROP = auto() # Delete property: obj, key -> bool
34→
35→ # Arrays/Objects
36→ BUILD_ARRAY = auto() # Build array from stack: arg = element count
37→ BUILD_OBJECT = auto() # Build object from stack: arg = property count
38→ BUILD_REGEX = auto() # Build regex from constant: constant index points to (pattern, flags) tuple
39→
40→ # Arithmetic
41→ ADD = auto()
42→ SUB = auto()
43→ MUL = auto()
44→ DIV = auto()
45→ MOD = auto()
46→ POW = auto()
47→ NEG = auto() # Unary minus
48→ POS = auto() # Unary plus
49→
50→ # Bitwise
51→ BAND = auto() # Bitwise AND
52→ BOR = auto() # Bitwise OR
53→ BXOR = auto() # Bitwise XOR
54→ BNOT = auto() # Bitwise NOT
55→ SHL = auto() # Shift left
56→ SHR = auto() # Shift right (signed)
57→ USHR = auto() # Shift right (unsigned)
58→
59→ # Comparison
60→ LT = auto() # Less than
61→ LE = auto() # Less than or equal
62→ GT = auto() # Greater than
63→ GE = auto() # Greater than or equal
64→ EQ = auto() # Equal (==)
65→ NE = auto() # Not equal (!=)
66→ SEQ = auto() # Strict equal (===)
67→ SNE = auto() # Strict not equal (!==)
68→
69→ # Logical
70→ NOT = auto() # Logical NOT
71→ # && and || are handled by conditional jumps
72→
73→ # Type operations
74→ TYPEOF = auto() # typeof operator
75→ INSTANCEOF = auto() # instanceof operator
76→ IN = auto() # in operator
77→
78→ # Control flow
79→ JUMP = auto() # Unconditional jump: arg = offset
80→ JUMP_IF_FALSE = auto() # Conditional jump: arg = offset
81→ JUMP_IF_TRUE = auto() # Conditional jump: arg = offset
82→
83→ # Function operations
84→ CALL = auto() # Call function: arg = argument count
85→ CALL_METHOD = auto() # Call method: arg = argument count
86→ RETURN = auto() # Return from function
87→ RETURN_UNDEFINED = auto() # Return undefined from function
88→
89→ # Object operations
90→ NEW = auto() # New object: arg = argument count
91→ THIS = auto() # Load 'this' value
92→
93→ # Exception handling
94→ THROW = auto() # Throw exception
95→ TRY_START = auto() # Start try block: arg = catch offset
96→ TRY_END = auto() # End try block
97→ CATCH = auto() # Catch handler
98→
99→ # Iteration
100→ FOR_IN_INIT = auto() # Initialize for-in: obj -> iterator
101→ FOR_IN_NEXT = auto() # Get next for-in: iterator -> key, done
102→ FOR_OF_INIT = auto() # Initialize for-of: iterable -> iterator
103→ FOR_OF_NEXT = auto() # Get next for-of: iterator -> value, done
104→
105→ # Increment/Decrement
106→ INC = auto() # Increment
107→ DEC = auto() # Decrement
108→ POST_INC = auto() # Post-increment (returns old value)
109→ POST_DEC = auto() # Post-decrement (returns old value)
110→
111→ # Closures
112→ MAKE_CLOSURE = auto() # Create closure: arg = function index
113→ LOAD_CLOSURE = auto() # Load from closure: arg = closure slot (for inner function)
114→ STORE_CLOSURE = auto() # Store to closure: arg = closure slot (for inner function)
115→ LOAD_CELL = auto() # Load from cell: arg = cell slot (for outer function)
116→ STORE_CELL = auto() # Store to cell: arg = cell slot (for outer function)
117→
118→
119→def disassemble(bytecode: bytes, constants: list) -> str:
120→ """Disassemble bytecode for debugging."""
121→ lines = []
122→ i = 0
123→ while i < len(bytecode):
124→ op = OpCode(bytecode[i])
125→ line = f"{i:4d}: {op.name}"
126→
127→ if op in (
128→ OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME,
129→ OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL,
130→ OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE,
131→ OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
132→ OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
133→ OpCode.TRY_START, OpCode.MAKE_CLOSURE,
134→ ):
135→ # Has argument
136→ if i + 1 < len(bytecode):
137→ arg = bytecode[i + 1]
138→ if op == OpCode.LOAD_CONST and arg < len(constants):
139→ line += f" {arg} ({constants[arg]!r})"
140→ else:
141→ line += f" {arg}"
142→ i += 2
143→ else:
144→ i += 1
145→ else:
146→ i += 1
147→
148→ lines.append(line)
149→
150→ return "\n".join(lines)
151→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
src/mquickjs_python/vm.py:483: elif op == OpCode.TYPEOF: src/mquickjs_python/parser.py:86: TokenType.VAR, TokenType.NEW, TokenType.DELETE, TokenType.TYPEOF, src/mquickjs_python/parser.py:649: TokenType.TYPEOF, TokenType.VOID, TokenType.DELETE, src/mquickjs_python/compiler.py:1102: "typeof": OpCode.TYPEOF, src/mquickjs_python/tokens.py:44: TYPEOF = auto() src/mquickjs_python/tokens.py:140: "typeof": TokenType.TYPEOF, src/mquickjs_python/opcodes.py:74: TYPEOF = auto() # typeof operator
Now let me look at how typeof is compiled. I need to see the compiler to understand how it handles typeof, and then I need to add a special case for typeof with an identifier operand to not throw ReferenceError.
{
"-B": 5,
"-C": 10,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"pattern": "typeof"
}1092- self._compile_expression(prop.value)
1093- self._emit(OpCode.BUILD_OBJECT, len(node.properties))
1094-
1095- elif isinstance(node, UnaryExpression):
1096- self._compile_expression(node.argument)
1097- op_map = {
1098- "-": OpCode.NEG,
1099- "+": OpCode.POS,
1100- "!": OpCode.NOT,
1101- "~": OpCode.BNOT,
1102: "typeof": OpCode.TYPEOF,
1103- }
1104- if node.operator in op_map:
1105- self._emit(op_map[node.operator])
1106- elif node.operator == "delete":
1107- # Handle delete specially
1108- if isinstance(node.argument, MemberExpression):
1109- # Recompile as delete operation
1110- self._compile_expression(node.argument.object)
1111- if node.argument.computed:
1112- self._compile_expression(node.argument.property)I see! The problem is that typeof is compiled like other unary operators - it compiles the argument first (which may throw) and then applies TYPEOF. But for typeof identifier we need special handling.
The solution is to either:
1. Add a new opcode TYPEOF_NAME that does both lookup and typeof, returning "undefined" if not found
2. Modify the compiler to handle typeof identifier specially
Let me add a TYPEOF_NAME opcode that takes a name index and returns "undefined" if the variable doesn't exist.
First, let me see the full context of the UnaryExpression compilation:
I see the issue. The compiler compiles typeof unknown_var as:
1. LOAD_NAME "unknown_var" - throws ReferenceError
2. TYPEOF
I need to add a special opcode TYPEOF_NAME that handles the case where the variable doesn't exist. Let me implement this:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 50,
"offset": 1090
} 1090→ self._emit(OpCode.LOAD_CONST, kind_idx)
1091→ # Value
1092→ self._compile_expression(prop.value)
1093→ self._emit(OpCode.BUILD_OBJECT, len(node.properties))
1094→
1095→ elif isinstance(node, UnaryExpression):
1096→ self._compile_expression(node.argument)
1097→ op_map = {
1098→ "-": OpCode.NEG,
1099→ "+": OpCode.POS,
1100→ "!": OpCode.NOT,
1101→ "~": OpCode.BNOT,
1102→ "typeof": OpCode.TYPEOF,
1103→ }
1104→ if node.operator in op_map:
1105→ self._emit(op_map[node.operator])
1106→ elif node.operator == "delete":
1107→ # Handle delete specially
1108→ if isinstance(node.argument, MemberExpression):
1109→ # Recompile as delete operation
1110→ self._compile_expression(node.argument.object)
1111→ if node.argument.computed:
1112→ self._compile_expression(node.argument.property)
1113→ else:
1114→ idx = self._add_constant(node.argument.property.name)
1115→ self._emit(OpCode.LOAD_CONST, idx)
1116→ self._emit(OpCode.DELETE_PROP)
1117→ else:
1118→ self._emit(OpCode.LOAD_TRUE) # delete on non-property returns true
1119→ elif node.operator == "void":
1120→ # void evaluates argument for side effects, returns undefined
1121→ self._emit(OpCode.POP) # Discard the argument value
1122→ self._emit(OpCode.LOAD_UNDEFINED)
1123→ else:
1124→ raise NotImplementedError(f"Unary operator: {node.operator}")
1125→
1126→ elif isinstance(node, UpdateExpression):
1127→ # ++x or x++
1128→ if isinstance(node.argument, Identifier):
1129→ name = node.argument.name
1130→ inc_op = OpCode.INC if node.operator == "++" else OpCode.DEC
1131→
1132→ # Check if it's a cell var (local that's captured by inner function)
1133→ cell_slot = self._get_cell_var(name)
1134→ if cell_slot is not None:
1135→ self._emit(OpCode.LOAD_CELL, cell_slot)
1136→ if node.prefix:
1137→ self._emit(inc_op)
1138→ self._emit(OpCode.DUP)
1139→ self._emit(OpCode.STORE_CELL, cell_slot)
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
Now I need to add a special case for typeof identifier where the argument is an Identifier node. I'll:
typeof identifierLet me also update the todo list since I'm working on making test_language.js pass.
Todos have been modified successfully. Ensure that you continue to use the todo list to track your progress. Please proceed with the current tasks if applicable
# Type operations
TYPEOF = auto() # typeof operator
INSTANCEOF = auto() # instanceof operator
IN = auto() # in operator # Type operations
TYPEOF = auto() # typeof operator
TYPEOF_NAME = auto() # typeof with name lookup (returns "undefined" for undeclared vars)
INSTANCEOF = auto() # instanceof operator
IN = auto() # in operatorThe file /home/user/mquickjs-python/src/mquickjs_python/opcodes.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
69→ # Logical
70→ NOT = auto() # Logical NOT
71→ # && and || are handled by conditional jumps
72→
73→ # Type operations
74→ TYPEOF = auto() # typeof operator
75→ TYPEOF_NAME = auto() # typeof with name lookup (returns "undefined" for undeclared vars)
76→ INSTANCEOF = auto() # instanceof operator
77→ IN = auto() # in operator
78→
79→ # Control flow
80→ JUMP = auto() # Unconditional jump: arg = offset
81→ JUMP_IF_FALSE = auto() # Conditional jump: arg = offsetNow I need to:
1. Add TYPEOF_NAME to the disassemble function in opcodes.py
2. Modify the compiler to use TYPEOF_NAME for typeof identifier
3. Implement TYPEOF_NAME in the VM
Let me update the disassemble function first:
if op in (
OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME,
OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL,
OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE,
OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
OpCode.TRY_START, OpCode.MAKE_CLOSURE,
): if op in (
OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME,
OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL,
OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE,
OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
OpCode.TRY_START, OpCode.MAKE_CLOSURE, OpCode.TYPEOF_NAME,
):The file /home/user/mquickjs-python/src/mquickjs_python/opcodes.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
124→ while i < len(bytecode):
125→ op = OpCode(bytecode[i])
126→ line = f"{i:4d}: {op.name}"
127→
128→ if op in (
129→ OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME,
130→ OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL,
131→ OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE,
132→ OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
133→ OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
134→ OpCode.TRY_START, OpCode.MAKE_CLOSURE, OpCode.TYPEOF_NAME,
135→ ):
136→ # Has argument
137→ if i + 1 < len(bytecode):
138→ arg = bytecode[i + 1]
139→ if op == OpCode.LOAD_CONST and arg < len(constants):{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 50,
"offset": 1
} 1→"""Bytecode compiler - compiles AST to bytecode."""
2→
3→from typing import List, Dict, Any, Optional, Tuple
4→from dataclasses import dataclass, field
5→from .ast_nodes import (
6→ Node, Program, NumericLiteral, StringLiteral, BooleanLiteral, NullLiteral,
7→ RegexLiteral, Identifier, ThisExpression, ArrayExpression, ObjectExpression, Property,
8→ UnaryExpression, UpdateExpression, BinaryExpression, LogicalExpression,
9→ ConditionalExpression, AssignmentExpression, SequenceExpression,
10→ MemberExpression, CallExpression, NewExpression,
11→ ExpressionStatement, BlockStatement, EmptyStatement,
12→ VariableDeclaration, VariableDeclarator,
13→ IfStatement, WhileStatement, DoWhileStatement, ForStatement,
14→ ForInStatement, ForOfStatement, BreakStatement, ContinueStatement,
15→ ReturnStatement, ThrowStatement, TryStatement, CatchClause,
16→ SwitchStatement, SwitchCase, LabeledStatement,
17→ FunctionDeclaration, FunctionExpression, ArrowFunctionExpression,
18→)
19→from .opcodes import OpCode
20→from .values import UNDEFINED
21→
22→
23→@dataclass
24→class CompiledFunction:
25→ """A compiled function."""
26→ name: str
27→ params: List[str]
28→ bytecode: bytes
29→ constants: List[Any]
30→ locals: List[str]
31→ num_locals: int
32→ free_vars: List[str] = field(default_factory=list) # Variables captured from outer scope
33→ cell_vars: List[str] = field(default_factory=list) # Local variables that are captured by inner functions
34→
35→
36→@dataclass
37→class LoopContext:
38→ """Context for loops (for break/continue)."""
39→ break_jumps: List[int] = field(default_factory=list)
40→ continue_jumps: List[int] = field(default_factory=list)
41→ label: Optional[str] = None
42→ is_loop: bool = True # False for switch statements (break only, no continue)
43→
44→
45→@dataclass
46→class TryContext:
47→ """Context for try-finally blocks (for break/continue/return)."""
48→ finalizer: Any = None # The finally block AST node
49→
50→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
Good, I see the structure. Now let me modify the UnaryExpression handling to use TYPEOF_NAME for typeof identifier:
elif isinstance(node, UnaryExpression):
self._compile_expression(node.argument)
op_map = {
"-": OpCode.NEG,
"+": OpCode.POS,
"!": OpCode.NOT,
"~": OpCode.BNOT,
"typeof": OpCode.TYPEOF,
}
if node.operator in op_map:
self._emit(op_map[node.operator]) elif isinstance(node, UnaryExpression):
# Special case for typeof with identifier - must not throw for undeclared vars
if node.operator == "typeof" and isinstance(node.argument, Identifier):
name = node.argument.name
# Check for local, cell, or closure vars first
local_slot = self._get_local(name)
cell_slot = self._get_cell_var(name)
closure_slot = self._get_closure_var(name)
if local_slot is not None:
self._emit(OpCode.LOAD_LOCAL, local_slot)
self._emit(OpCode.TYPEOF)
elif cell_slot is not None:
self._emit(OpCode.LOAD_CELL, cell_slot)
self._emit(OpCode.TYPEOF)
elif closure_slot is not None:
self._emit(OpCode.LOAD_CLOSURE, closure_slot)
self._emit(OpCode.TYPEOF)
else:
# Use TYPEOF_NAME for global lookup - won't throw if undefined
idx = self._add_constant(name)
self._emit(OpCode.TYPEOF_NAME, idx)
else:
self._compile_expression(node.argument)
op_map = {
"-": OpCode.NEG,
"+": OpCode.POS,
"!": OpCode.NOT,
"~": OpCode.BNOT,
"typeof": OpCode.TYPEOF,
}
if node.operator in op_map:
self._emit(op_map[node.operator])The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
1091→ # Value
1092→ self._compile_expression(prop.value)
1093→ self._emit(OpCode.BUILD_OBJECT, len(node.properties))
1094→
1095→ elif isinstance(node, UnaryExpression):
1096→ # Special case for typeof with identifier - must not throw for undeclared vars
1097→ if node.operator == "typeof" and isinstance(node.argument, Identifier):
1098→ name = node.argument.name
1099→ # Check for local, cell, or closure vars first
1100→ local_slot = self._get_local(name)
1101→ cell_slot = self._get_cell_var(name)
1102→ closure_slot = self._get_closure_var(name)
1103→ if local_slot is not None:
1104→ self._emit(OpCode.LOAD_LOCAL, local_slot)
1105→ self._emit(OpCode.TYPEOF)
1106→ elif cell_slot is not None:
1107→ self._emit(OpCode.LOAD_CELL, cell_slot)
1108→ self._emit(OpCode.TYPEOF)
1109→ elif closure_slot is not None:
1110→ self._emit(OpCode.LOAD_CLOSURE, closure_slot)
1111→ self._emit(OpCode.TYPEOF)
1112→ else:
1113→ # Use TYPEOF_NAME for global lookup - won't throw if undefined
1114→ idx = self._add_constant(name)
1115→ self._emit(OpCode.TYPEOF_NAME, idx)
1116→ else:
1117→ self._compile_expression(node.argument)
1118→ op_map = {
1119→ "-": OpCode.NEG,
1120→ "+": OpCode.POS,
1121→ "!": OpCode.NOT,
1122→ "~": OpCode.BNOT,
1123→ "typeof": OpCode.TYPEOF,
1124→ }
1125→ if node.operator in op_map:
1126→ self._emit(op_map[node.operator])
1127→ elif node.operator == "delete":
1128→ # Handle delete specially
1129→ if isinstance(node.argument, MemberExpression):
1130→ # Recompile as delete operationHmm, I see a problem - the elif statements below are now broken because the if node.operator == "typeof" block already handles that case. Let me read more context to fix the issue:
I see there's an issue with the structure. Let me check more context to fix the elif clause:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"limit": 30,
"offset": 1125
} 1125→ if node.operator in op_map:
1126→ self._emit(op_map[node.operator])
1127→ elif node.operator == "delete":
1128→ # Handle delete specially
1129→ if isinstance(node.argument, MemberExpression):
1130→ # Recompile as delete operation
1131→ self._compile_expression(node.argument.object)
1132→ if node.argument.computed:
1133→ self._compile_expression(node.argument.property)
1134→ else:
1135→ idx = self._add_constant(node.argument.property.name)
1136→ self._emit(OpCode.LOAD_CONST, idx)
1137→ self._emit(OpCode.DELETE_PROP)
1138→ else:
1139→ self._emit(OpCode.LOAD_TRUE) # delete on non-property returns true
1140→ elif node.operator == "void":
1141→ # void evaluates argument for side effects, returns undefined
1142→ self._emit(OpCode.POP) # Discard the argument value
1143→ self._emit(OpCode.LOAD_UNDEFINED)
1144→ else:
1145→ raise NotImplementedError(f"Unary operator: {node.operator}")
1146→
1147→ elif isinstance(node, UpdateExpression):
1148→ # ++x or x++
1149→ if isinstance(node.argument, Identifier):
1150→ name = node.argument.name
1151→ inc_op = OpCode.INC if node.operator == "++" else OpCode.DEC
1152→
1153→ # Check if it's a cell var (local that's captured by inner function)
1154→ cell_slot = self._get_cell_var(name)
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see the problem. The elif node.operator == "delete" is indented at the wrong level. After my edit, the structure is broken. I need to fix the code structure to handle the else branch from the if statement properly.
Looking at it:
- First if handles typeof identifier
- The else handles regular operators (not typeof with identifier)
But inside the else, we have:
if node.operator in op_map: # includes typeof
self._emit(...)
elif node.operator == "delete": # BUT this is now at wrong indentation
The issue is that "delete" and "void" should also be handled in the else clause, but they were moved out. Let me fix this:
else:
self._compile_expression(node.argument)
op_map = {
"-": OpCode.NEG,
"+": OpCode.POS,
"!": OpCode.NOT,
"~": OpCode.BNOT,
"typeof": OpCode.TYPEOF,
}
if node.operator in op_map:
self._emit(op_map[node.operator])
elif node.operator == "delete":
# Handle delete specially
if isinstance(node.argument, MemberExpression):
# Recompile as delete operation
self._compile_expression(node.argument.object)
if node.argument.computed:
self._compile_expression(node.argument.property)
else:
idx = self._add_constant(node.argument.property.name)
self._emit(OpCode.LOAD_CONST, idx)
self._emit(OpCode.DELETE_PROP)
else:
self._emit(OpCode.LOAD_TRUE) # delete on non-property returns true
elif node.operator == "void":
# void evaluates argument for side effects, returns undefined
self._emit(OpCode.POP) # Discard the argument value
self._emit(OpCode.LOAD_UNDEFINED)
else:
raise NotImplementedError(f"Unary operator: {node.operator}") elif node.operator == "delete":
# Handle delete specially - don't compile argument normally
if isinstance(node.argument, MemberExpression):
# Compile as delete operation
self._compile_expression(node.argument.object)
if node.argument.computed:
self._compile_expression(node.argument.property)
else:
idx = self._add_constant(node.argument.property.name)
self._emit(OpCode.LOAD_CONST, idx)
self._emit(OpCode.DELETE_PROP)
else:
self._emit(OpCode.LOAD_TRUE) # delete on non-property returns true
elif node.operator == "void":
# void evaluates argument for side effects, returns undefined
self._compile_expression(node.argument)
self._emit(OpCode.POP) # Discard the argument value
self._emit(OpCode.LOAD_UNDEFINED)
else:
self._compile_expression(node.argument)
op_map = {
"-": OpCode.NEG,
"+": OpCode.POS,
"!": OpCode.NOT,
"~": OpCode.BNOT,
"typeof": OpCode.TYPEOF,
}
if node.operator in op_map:
self._emit(op_map[node.operator])
else:
raise NotImplementedError(f"Unary operator: {node.operator}")The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
1112→ else:
1113→ # Use TYPEOF_NAME for global lookup - won't throw if undefined
1114→ idx = self._add_constant(name)
1115→ self._emit(OpCode.TYPEOF_NAME, idx)
1116→ elif node.operator == "delete":
1117→ # Handle delete specially - don't compile argument normally
1118→ if isinstance(node.argument, MemberExpression):
1119→ # Compile as delete operation
1120→ self._compile_expression(node.argument.object)
1121→ if node.argument.computed:
1122→ self._compile_expression(node.argument.property)
1123→ else:
1124→ idx = self._add_constant(node.argument.property.name)
1125→ self._emit(OpCode.LOAD_CONST, idx)
1126→ self._emit(OpCode.DELETE_PROP)
1127→ else:
1128→ self._emit(OpCode.LOAD_TRUE) # delete on non-property returns true
1129→ elif node.operator == "void":
1130→ # void evaluates argument for side effects, returns undefined
1131→ self._compile_expression(node.argument)
1132→ self._emit(OpCode.POP) # Discard the argument value
1133→ self._emit(OpCode.LOAD_UNDEFINED)
1134→ else:
1135→ self._compile_expression(node.argument)
1136→ op_map = {
1137→ "-": OpCode.NEG,
1138→ "+": OpCode.POS,
1139→ "!": OpCode.NOT,
1140→ "~": OpCode.BNOT,
1141→ "typeof": OpCode.TYPEOF,
1142→ }
1143→ if node.operator in op_map:
1144→ self._emit(op_map[node.operator])
1145→ else:
1146→ raise NotImplementedError(f"Unary operator: {node.operator}")
1147→
1148→ elif isinstance(node, UpdateExpression):
1149→ # ++x or x++
1150→ if isinstance(node.argument, Identifier):Good, now I need to implement TYPEOF_NAME in the VM. Let me read the VM and find where TYPEOF is implemented:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 30,
"offset": 480
} 480→ self.stack.append(not to_boolean(a))
481→
482→ # Type operations
483→ elif op == OpCode.TYPEOF:
484→ a = self.stack.pop()
485→ self.stack.append(js_typeof(a))
486→
487→ elif op == OpCode.INSTANCEOF:
488→ constructor = self.stack.pop()
489→ obj = self.stack.pop()
490→ # Check if constructor is callable
491→ if not (isinstance(constructor, JSFunction) or
492→ (isinstance(constructor, JSObject) and hasattr(constructor, '_call_fn'))):
493→ raise JSTypeError("Right-hand side of instanceof is not callable")
494→
495→ # Check prototype chain
496→ if not isinstance(obj, JSObject):
497→ self.stack.append(False)
498→ else:
499→ # Get constructor's prototype property
500→ if isinstance(constructor, JSFunction) and hasattr(constructor, '_prototype'):
501→ proto = constructor._prototype
502→ elif isinstance(constructor, JSObject) and hasattr(constructor, '_prototype'):
503→ proto = constructor._prototype
504→ else:
505→ proto = constructor.get("prototype") if isinstance(constructor, JSObject) else None
506→
507→ # Walk the prototype chain
508→ result = False
509→ current = getattr(obj, '_prototype', None)
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I need to add TYPEOF_NAME after TYPEOF. Let me also check where constants are accessed in the VM:
{
"-n": true,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "constants\\["
}214: self.stack.append(frame.func.constants[arg]) 236: name = frame.func.constants[arg] 243: name = frame.func.constants[arg] 325: pattern, flags = frame.func.constants[arg] 706: name = frame.func.constants[index]
Good. I can see that frame.func.constants[arg] is used to access constants. Now let me add TYPEOF_NAME implementation. I also need to see how LOAD_NAME is implemented to understand the lookup mechanism:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 30,
"offset": 230
} 230→ self.stack.append(frame.locals[arg])
231→
232→ elif op == OpCode.STORE_LOCAL:
233→ frame.locals[arg] = self.stack[-1]
234→
235→ elif op == OpCode.LOAD_NAME:
236→ name = frame.func.constants[arg]
237→ if name in self.globals:
238→ self.stack.append(self.globals[name])
239→ else:
240→ raise JSReferenceError(f"{name} is not defined")
241→
242→ elif op == OpCode.STORE_NAME:
243→ name = frame.func.constants[arg]
244→ self.globals[name] = self.stack[-1]
245→
246→ elif op == OpCode.LOAD_CLOSURE:
247→ if frame.closure_cells and arg < len(frame.closure_cells):
248→ self.stack.append(frame.closure_cells[arg].value)
249→ else:
250→ raise JSReferenceError("Closure variable not found")
251→
252→ elif op == OpCode.STORE_CLOSURE:
253→ if frame.closure_cells and arg < len(frame.closure_cells):
254→ frame.closure_cells[arg].value = self.stack[-1]
255→ else:
256→ raise JSReferenceError("Closure variable not found")
257→
258→ elif op == OpCode.LOAD_CELL:
259→ if frame.cell_storage and arg < len(frame.cell_storage):
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
# Type operations
elif op == OpCode.TYPEOF:
a = self.stack.pop()
self.stack.append(js_typeof(a))
elif op == OpCode.INSTANCEOF: # Type operations
elif op == OpCode.TYPEOF:
a = self.stack.pop()
self.stack.append(js_typeof(a))
elif op == OpCode.TYPEOF_NAME:
# Special typeof that returns "undefined" for undeclared variables
name = frame.func.constants[arg]
if name in self.globals:
self.stack.append(js_typeof(self.globals[name]))
else:
self.stack.append("undefined")
elif op == OpCode.INSTANCEOF:The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
478→ elif op == OpCode.NOT:
479→ a = self.stack.pop()
480→ self.stack.append(not to_boolean(a))
481→
482→ # Type operations
483→ elif op == OpCode.TYPEOF:
484→ a = self.stack.pop()
485→ self.stack.append(js_typeof(a))
486→
487→ elif op == OpCode.TYPEOF_NAME:
488→ # Special typeof that returns "undefined" for undeclared variables
489→ name = frame.func.constants[arg]
490→ if name in self.globals:
491→ self.stack.append(js_typeof(self.globals[name]))
492→ else:
493→ self.stack.append("undefined")
494→
495→ elif op == OpCode.INSTANCEOF:
496→ constructor = self.stack.pop()
497→ obj = self.stack.pop()
498→ # Check if constructor is callable
499→ if not (isinstance(constructor, JSFunction) ortests/test_vm.py::TestArrays::test_array_length PASSED [ 58%] tests/test_vm.py::TestObjects::test_object_literal PASSED [ 60%] tests/test_vm.py::TestObjects::test_object_property_access PASSED [ 61%] tests/test_vm.py::TestObjects::test_object_property_set PASSED [ 63%] tests/test_vm.py::TestStrings::test_string_concatenation PASSED [ 64%] tests/test_vm.py::TestStrings::test_string_length PASSED [ 66%] tests/test_vm.py::TestGlobalAccess::test_set_global PASSED [ 67%] tests/test_vm.py::TestGlobalAccess::test_get_global PASSED [ 69%] tests/test_vm.py::TestVoidOperator::test_void_returns_undefined PASSED [ 70%] tests/test_vm.py::TestVoidOperator::test_void_expression PASSED [ 72%] tests/test_vm.py::TestVoidOperator::test_void_function_call PASSED [ 73%] tests/test_vm.py::TestForOf::test_for_of_array PASSED [ 75%] tests/test_vm.py::TestForOf::test_for_of_string PASSED [ 76%] tests/test_vm.py::TestGetterSetter::test_getter PASSED [ 78%] tests/test_vm.py::TestGetterSetter::test_setter PASSED [ 80%] tests/test_vm.py::TestGetterSetter::test_getter_setter_combined PASSED [ 81%] tests/test_vm.py::TestTryFinallyBreak::test_break_in_try_finally PASSED [ 83%] tests/test_vm.py::TestLabeledStatements::test_labeled_break_after_while PASSED [ 84%] tests/test_vm.py::TestLabeledStatements::test_labeled_break_in_block PASSED [ 86%] tests/test_vm.py::TestBuiltinConstructors::test_new_object PASSED [ 87%] tests/test_vm.py::TestBuiltinConstructors::test_new_array PASSED [ 89%] tests/test_vm.py::TestBuiltinConstructors::test_new_array_with_elements PASSED [ 90%] tests/test_vm.py::TestASI::test_break_asi_newline PASSED [ 92%] tests/test_vm.py::TestASI::test_continue_asi_newline PASSED [ 93%] tests/test_vm.py::TestMemberUpdate::test_object_property_postfix_increment PASSED [ 95%] tests/test_vm.py::TestMemberUpdate::test_object_property_prefix_increment PASSED [ 96%] tests/test_vm.py::TestMemberUpdate::test_array_element_postfix_increment PASSED [ 98%] tests/test_vm.py::TestMemberUpdate::test_object_property_decrement PASSED [100%] ============================== 65 passed in 0.20s ==============================
All tests pass. Now let me run the test_language.js test to see if the typeof issue is fixed:
uv run pytest tests/test_js_compat.py -x -v -k "test_language" 2>&1 | tail -40
============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python cachedir: .pytest_cache rootdir: /home/user/mquickjs-python configfile: pyproject.toml collecting ... collected 0 items ============================ no tests ran in 0.00s ============================= ERROR: file or directory not found: tests/test_js_compat.py
/home/user/mquickjs-python/tests/test_basic.py /home/user/mquickjs-python/tests/test_lexer.py /home/user/mquickjs-python/tests/test_parser.py /home/user/mquickjs-python/tests/conftest.py /home/user/mquickjs-python/tests/test_jscontext_regexp.py /home/user/mquickjs-python/tests/test_string_regex.py /home/user/mquickjs-python/tests/test_arrow_functions.py /home/user/mquickjs-python/tests/test_function_methods.py /home/user/mquickjs-python/tests/test_compatibility.py /home/user/mquickjs-python/tests/test_js_basic.py /home/user/mquickjs-python/tests/test_regex.py /home/user/mquickjs-python/tests/test_vm.py
1→"""
2→Parameterized pytest tests for JavaScript files.
3→
4→- Each .js file in tests/basic/ is run as a test case (should pass)
5→- Each .js file in tests/compat/ are passing original mquickjs tests
6→- Each .js file in tests/ (original mquickjs tests) is run with xfail (expected to fail)
7→"""
8→from pathlib import Path
9→
10→import pytest
11→
12→from mquickjs_python import JSContext
13→
14→
15→def get_basic_test_files():
16→ """Discover all .js files in tests/basic/ directory."""
17→ basic_dir = Path(__file__).parent / "basic"
18→ if not basic_dir.exists():
19→ return []
20→ js_files = sorted(basic_dir.glob("*.js"))
21→ return [(f.name, f) for f in js_files]
22→
23→
24→def get_compat_test_files():
25→ """Discover passing original mquickjs .js test files in tests/compat/ directory."""
26→ compat_dir = Path(__file__).parent / "compat"
27→ if not compat_dir.exists():
28→ return []
29→ js_files = sorted(compat_dir.glob("*.js"))
30→ return [(f.name, f) for f in js_files]
31→
32→
33→def get_mquickjs_test_files():
34→ """Discover original mquickjs .js test files in tests/ directory."""
35→ tests_dir = Path(__file__).parent
36→ # Get all .js files directly in tests/ (not in subdirectories)
37→ js_files = sorted(tests_dir.glob("*.js"))
38→ return [(f.name, f) for f in js_files]
39→
40→
41→@pytest.mark.parametrize(
42→ "name,path",
43→ get_basic_test_files(),
44→ ids=lambda x: x if isinstance(x, str) else None,
45→)
46→def test_basic_js(name: str, path: Path):
47→ """Run a basic JavaScript test file."""
48→ source = path.read_text(encoding="utf-8")
49→ ctx = JSContext()
50→ # Execute the script - if it throws, the test fails
51→ ctx.eval(source)
52→
53→
54→@pytest.mark.parametrize(
55→ "name,path",
56→ get_compat_test_files(),
57→ ids=lambda x: x if isinstance(x, str) else None,
58→)
59→def test_compat_js(name: str, path: Path):
60→ """Run a passing original mquickjs JavaScript test file.
61→
62→ These are tests from the original C mquickjs implementation
63→ that now pass in our Python implementation.
64→ """
65→ source = path.read_text(encoding="utf-8")
66→ ctx = JSContext(time_limit=2.0)
67→ # Execute the script - if it throws, the test fails
68→ ctx.eval(source)
69→
70→
71→@pytest.mark.parametrize(
72→ "name,path",
73→ get_mquickjs_test_files(),
74→ ids=lambda x: x if isinstance(x, str) else None,
75→)
76→@pytest.mark.xfail(reason="Original mquickjs tests - not yet passing")
77→def test_mquickjs_js(name: str, path: Path):
78→ """Run an original mquickjs JavaScript test file.
79→
80→ These tests are expected to fail until the VM is complete.
81→ Watch for xfail tests that start passing!
82→ """
83→ source = path.read_text(encoding="utf-8")
84→ ctx = JSContext(time_limit=2.0) # Timeout to avoid infinite loops
85→ # Execute the script - if it throws, the test fails
86→ ctx.eval(source)
87→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see. The test_language.js is in tests/ and is run through test_js_basic.py via the test_mquickjs_js test function. Let me run that test:
uv run pytest tests/test_js_basic.py -x -v -k "test_language" 2>&1 | tail -50
============================= test session starts ============================== platform linux -- Python 3.11.14, pytest-9.0.2, pluggy-1.6.0 -- /home/user/mquickjs-python/.venv/bin/python cachedir: .pytest_cache rootdir: /home/user/mquickjs-python configfile: pyproject.toml collecting ... collected 26 items / 25 deselected / 1 selected tests/test_js_basic.py::test_mquickjs_js[test_language.js-path3] XFAIL [100%] ====================== 25 deselected, 1 xfailed in 0.33s =======================
uv run python -c "
from mquickjs_python import JSContext
source = open('tests/test_language.js').read()
ctx = JSContext(time_limit=2.0)
try:
ctx.eval(source)
print('PASSED')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1The _get_closure_var method doesn't exist in the Compiler. Let me check what methods exist:
{
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/compiler.py",
"pattern": "def _get_"
}156: def _get_local(self, name: str) -> Optional[int]: 162: def _get_free_var(self, name: str) -> Optional[int]: 181: def _get_cell_var(self, name: str) -> Optional[int]:
if node.operator == "typeof" and isinstance(node.argument, Identifier):
name = node.argument.name
# Check for local, cell, or closure vars first
local_slot = self._get_local(name)
cell_slot = self._get_cell_var(name)
closure_slot = self._get_closure_var(name) if node.operator == "typeof" and isinstance(node.argument, Identifier):
name = node.argument.name
# Check for local, cell, or closure vars first
local_slot = self._get_local(name)
cell_slot = self._get_cell_var(name)
closure_slot = self._get_free_var(name)The file /home/user/mquickjs-python/src/mquickjs_python/compiler.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 1093→ self._emit(OpCode.BUILD_OBJECT, len(node.properties)) 1094→ 1095→ elif isinstance(node, UnaryExpression): 1096→ # Special case for typeof with identifier - must not throw for undeclared vars 1097→ if node.operator == "typeof" and isinstance(node.argument, Identifier): 1098→ name = node.argument.name 1099→ # Check for local, cell, or closure vars first 1100→ local_slot = self._get_local(name) 1101→ cell_slot = self._get_cell_var(name) 1102→ closure_slot = self._get_free_var(name) 1103→ if local_slot is not None: 1104→ self._emit(OpCode.LOAD_LOCAL, local_slot) 1105→ self._emit(OpCode.TYPEOF) 1106→ elif cell_slot is not None:
uv run python -c "
from mquickjs_python import JSContext
source = open('tests/test_language.js').read()
ctx = JSContext(time_limit=2.0)
try:
ctx.eval(source)
print('PASSED')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1There's a bug in my code - I'm checking closure_slot but passing None as an index. Let me check what's happening. The issue is that when I do closure_slot = self._get_free_var(name) and then use it with LOAD_CLOSURE, if it's None the check is needed. Let me verify by adding better debugging:
uv run python -c "
from mquickjs_python import JSContext
code = '''
typeof x // x is not defined
'''
ctx = JSContext()
try:
result = ctx.eval(code)
print(f'Result: {result}')
except Exception as e:
import traceback
traceback.print_exc()
" 2>&1Traceback (most recent call last):
File "<string>", line 8, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 634, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 489, in _execute_opcode
name = frame.func.constants[arg]
~~~~~~~~~~~~~~~~~~~~^^^^^
TypeError: list indices must be integers or slices, not NoneTypeAh! I see the issue. The TYPEOF_NAME opcode takes an argument but the VM is trying to read arg which is None if I didn't check for it. Let me look at how opcodes with arguments are dispatched:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 50,
"offset": 130
}130→ while self.call_stack: 131→ self._check_limits() 132→ 133→ frame = self.call_stack[-1] 134→ func = frame.func 135→ bytecode = func.bytecode 136→ 137→ if frame.ip >= len(bytecode): 138→ # End of function 139→ return self.stack.pop() if self.stack else UNDEFINED 140→ 141→ op = OpCode(bytecode[frame.ip]) 142→ frame.ip += 1 143→ 144→ # Get argument if needed 145→ arg = None 146→ if op in (OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE, OpCode.TRY_START): 147→ # 16-bit little-endian argument for jumps 148→ low = bytecode[frame.ip] 149→ high = bytecode[frame.ip + 1] 150→ arg = low | (high << 8) 151→ frame.ip += 2 152→ elif op in ( 153→ OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME, 154→ OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL, 155→ OpCode.LOAD_CLOSURE, OpCode.STORE_CLOSURE, 156→ OpCode.LOAD_CELL, OpCode.STORE_CELL, 157→ OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW, 158→ OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX, 159→ OpCode.MAKE_CLOSURE, 160→ ): 161→ arg = bytecode[frame.ip] 162→ frame.ip += 1 163→ 164→ # Execute opcode 165→ self._execute_opcode(op, arg, frame) 166→ 167→ # Check if frame was popped (return) 168→ if not self.call_stack: 169→ break 170→ 171→ return self.stack.pop() if self.stack else UNDEFINED 172→ 173→ def _execute_opcode(self, op: OpCode, arg: Optional[int], frame: CallFrame) -> None: 174→ """Execute a single opcode.""" 175→ 176→ # Stack operations 177→ if op == OpCode.POP: 178→ if self.stack: 179→ self.stack.pop() <system-reminder> Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior. </system-reminder>
I see! The opcodes that need arguments are listed in a tuple. I need to add OpCode.TYPEOF_NAME to this tuple because it takes a constant index argument.
elif op in (
OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME,
OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL,
OpCode.LOAD_CLOSURE, OpCode.STORE_CLOSURE,
OpCode.LOAD_CELL, OpCode.STORE_CELL,
OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
OpCode.MAKE_CLOSURE,
): elif op in (
OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME,
OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL,
OpCode.LOAD_CLOSURE, OpCode.STORE_CLOSURE,
OpCode.LOAD_CELL, OpCode.STORE_CELL,
OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
OpCode.MAKE_CLOSURE, OpCode.TYPEOF_NAME,
):The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 148→ low = bytecode[frame.ip] 149→ high = bytecode[frame.ip + 1] 150→ arg = low | (high << 8) 151→ frame.ip += 2 152→ elif op in ( 153→ OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME, 154→ OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL, 155→ OpCode.LOAD_CLOSURE, OpCode.STORE_CLOSURE, 156→ OpCode.LOAD_CELL, OpCode.STORE_CELL, 157→ OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW, 158→ OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX, 159→ OpCode.MAKE_CLOSURE, OpCode.TYPEOF_NAME, 160→ ): 161→ arg = bytecode[frame.ip] 162→ frame.ip += 1 163→ 164→ # Execute opcode
uv run python -c "
from mquickjs_python import JSContext
code = '''
typeof x // x is not defined
'''
ctx = JSContext()
result = ctx.eval(code)
print(f'Result: {result!r}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
source = open('tests/test_language.js').read()
ctx = JSContext(time_limit=2.0)
try:
ctx.eval(source)
print('PASSED')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1There's still an error. Let me check what's happening by adding more context. Let me first look at the test_language.js file:
1→function throw_error(msg) {
2→ throw Error(msg);
3→}
4→
5→function assert(actual, expected, message) {
6→ function get_full_type(o) {
7→ var type = typeof(o);
8→ if (type === 'object') {
9→ if (o === null)
10→ return 'null';
11→ if (o.constructor && o.constructor.name)
12→ return o.constructor.name;
13→ }
14→ return type;
15→ }
16→
17→ if (arguments.length == 1)
18→ expected = true;
19→
20→ if (typeof actual === typeof expected) {
21→ if (actual === expected) {
22→ if (actual !== 0 || (1 / actual) === (1 / expected))
23→ return;
24→ }
25→ if (typeof actual === 'number') {
26→ if (isNaN(actual) && isNaN(expected))
27→ return true;
28→ }
29→ if (typeof actual === 'object') {
30→ if (actual !== null && expected !== null
31→ && actual.constructor === expected.constructor
32→ && actual.toString() === expected.toString())
33→ return;
34→ }
35→ }
36→ // Should output the source file and line number and extract
37→ // the expression from the assert call
38→ throw_error("assertion failed: got " +
39→ get_full_type(actual) + ":|" + actual + "|, expected " +
40→ get_full_type(expected) + ":|" + expected + "|" +
41→ (message ? " (" + message + ")" : ""));
42→}
43→
44→function assert_throws(expected_error, func)
45→{
46→ var err = false;
47→ try {
48→ func();
49→ } catch(e) {
50→ err = true;
51→ if (!(e instanceof expected_error)) {
52→ // Should output the source file and line number and extract
53→ // the expression from the assert_throws() call
54→ throw_error("unexpected exception type");
55→ return;
56→ }
57→ }
58→ if (!err) {
59→ // Should output the source file and line number and extract
60→ // the expression from the assert_throws() call
61→ throw_error("expected exception");
62→ }
63→}
64→
65→function test_op1()
66→{
67→ var r, a;
68→ r = 1 + 2;
69→ assert(r, 3);
70→
71→ r = 1 - 2;
72→ assert(r, -1);
73→
74→ r = -1;
75→ assert(r, -1, "-1 === -1");
76→
77→ r = +2;
78→ assert(r, 2, "+2 === 2");
79→
80→ r = 2 * 3;
81→ assert(r, 6, "2 * 3 === 6");
82→
83→ r = 4 / 2;
84→ assert(r, 2, "4 / 2 === 2");
85→
86→ r = 4 % 3;
87→ assert(r, 1, "4 % 3 === 3");
88→
89→ r = 4 << 2;
90→ assert(r, 16, "4 << 2 === 16");
91→
92→ r = 1 << 0;
93→ assert(r, 1, "1 << 0 === 1");
94→
95→ r = 1 << 29;
96→ assert(r, 536870912, "1 << 29 === 536870912");
97→
98→ r = 1 << 30;
99→ assert(r, 1073741824, "1 << 30 === 1073741824");
100→
101→ r = 1 << 31;
102→ assert(r, -2147483648, "1 << 31 === -2147483648");
103→
104→ r = 1 << 32;
105→ assert(r, 1, "1 << 32 === 1");
106→
107→ r = (1 << 31) < 0;
108→ assert(r, true, "(1 << 31) < 0 === true");
109→
110→ r = -4 >> 1;
111→ assert(r, -2, "-4 >> 1 === -2");
112→
113→ r = -4 >>> 1;
114→ assert(r, 0x7ffffffe, "-4 >>> 1 === 0x7ffffffe");
115→
116→ r = -1 >>> 0;
117→ assert(r, 0xffffffff);
118→
119→ r = 1 & 1;
120→ assert(r, 1, "1 & 1 === 1");
121→
122→ r = 0 | 1;
123→ assert(r, 1, "0 | 1 === 1");
124→
125→ r = 1 ^ 1;
126→ assert(r, 0, "1 ^ 1 === 0");
127→
128→ r = ~1;
129→ assert(r, -2, "~1 === -2");
130→
131→ r = !1;
132→ assert(r, false, "!1 === false");
133→
134→ assert((1 < 2), true, "(1 < 2) === true");
135→
136→ assert((2 > 1), true, "(2 > 1) === true");
137→
138→ assert(('b' > 'a'), true, "('b' > 'a') === true");
139→
140→ assert(2 ** 8, 256, "2 ** 8 === 256");
141→
142→ /* minus zero */
143→ assert(1/(-0.0), -Infinity);
144→ a = 0;
145→ assert(1/(-a), -Infinity);
146→ assert(1/(0 * -6), -Infinity);
147→
148→ /* 31 bit overflow */
149→ a = 0x3fffffff;
150→ assert(a + 1, 0x40000000);
151→ a = -0x40000000;
152→ assert(-a, 0x40000000);
153→}
154→
155→function test_cvt()
156→{
157→ assert((NaN | 0), 0);
158→ assert((Infinity | 0), 0);
159→ assert(((-Infinity) | 0), 0);
160→ assert(("12345" | 0), 12345);
161→ assert(("0x12345" | 0), 0x12345);
162→ assert(((4294967296 * 3 - 4) | 0), -4);
163→
164→ assert(("12345" >>> 0), 12345);
165→ assert(("0x12345" >>> 0), 0x12345);
166→ assert((NaN >>> 0), 0);
167→ assert((Infinity >>> 0), 0);
168→ assert(((-Infinity) >>> 0), 0);
169→ assert(((4294967296 * 3 - 4) >>> 0), (4294967296 - 4));
170→}
171→
172→function test_eq()
173→{
174→ assert(null == undefined);
175→ assert(undefined == null);
176→ assert(true == 1);
177→ assert(0 == false);
178→ assert("" == 0);
179→ assert("123" == 123);
180→ assert("122" != 123);
181→// assert((new Number(1)) == 1);
182→// assert(2 == (new Number(2)));
183→// assert((new String("abc")) == "abc");
184→// assert({} != "abc");
185→}
186→
187→function test_inc_dec()
188→{
189→ var a, r;
190→
191→ a = 1;
192→ r = a++;
193→ assert(r === 1 && a === 2);
194→
195→ a = 1;
196→ r = ++a;
197→ assert(r === 2 && a === 2);
198→
199→ a = 1;
200→ r = a--;
201→ assert(r === 1 && a === 0);
202→
203→ a = 1;
204→ r = --a;
205→ assert(r === 0 && a === 0);
206→
207→ a = {x:true};
208→ a.x++;
209→ assert(a.x, 2, "++");
210→
211→ a = {x:true};
212→ a.x--;
213→ assert(a.x, 0, "--");
214→
215→ a = [true];
216→ a[0]++;
217→ assert(a[0], 2, "++");
218→
219→ a = {x:true};
220→ r = a.x++;
221→ assert(r === 1 && a.x === 2);
222→
223→ a = {x:true};
224→ r = a.x--;
225→ assert(r === 1 && a.x === 0);
226→
227→ a = [true];
228→ r = a[0]++;
229→ assert(r === 1 && a[0] === 2);
230→
231→ a = [true];
232→ r = a[0]--;
233→ assert(r === 1 && a[0] === 0);
234→}
235→
236→function F(x)
237→{
238→ this.x = x;
239→}
240→
241→function test_op2()
242→{
243→ var a, b;
244→ a = new Object;
245→ a.x = 1;
246→ assert(a.x, 1, "new");
247→ b = new F(2);
248→ assert(b.x, 2, "new");
249→ assert((b instanceof F), true, "instanceof F");
250→
251→ a = {x : 2};
252→ assert(("x" in a), true, "in");
253→ assert(("y" in a), false, "in");
254→
255→ a = {};
256→ assert((a instanceof Object), true, "instanceof Object");
257→ assert((a instanceof String), false, "instanceof String");
258→
259→ assert((typeof 1), "number", "typeof");
260→ assert((typeof Object), "function", "typeof");
261→ assert((typeof null), "object", "typeof");
262→ assert((typeof unknown_var), "undefined", "typeof");
263→
264→ a = {x: 1, y: 1};
265→ assert((delete a.x), true, "delete");
266→ assert(("x" in a), false, "delete in");
267→
268→ a = {x: 1, if: 2};
269→ assert(a.if, 2);
270→
271→ a = {x: 1, y: 2, __proto__: { z: 3 }};
272→ assert(a.x, 1);
273→ assert(a.y, 2);
274→ assert(Object.getPrototypeOf(a).z, 3);
275→
276→ /* getter/setter/method */
277→ b = 2;
278→ a = {get x() { return b; }, set x(v) { b = v; }, f(v) { return v + 1 },
279→ set: 10, get: 11 };
280→ assert(a.x, 2);
281→ a.x = 3;
282→ assert(a.x, 3);
283→ assert(a.f(3), 4);
284→ assert(a.set, 10);
285→ assert(a.get, 11);
286→
287→ a = { set() { return 1; }, get() { return 2; }}
288→ assert(a.set(), 1);
289→ assert(a.get(), 2);
290→}
291→
292→function test_prototype()
293→{
294→ function f() { }
295→ assert(f.prototype.constructor, f, "prototype");
296→}
297→
298→function test_arguments()
299→{
300→ function f2() {
301→ assert(arguments.length, 2, "arguments");
302→ assert(arguments[0], 1, "arguments");
303→ assert(arguments[1], 3, "arguments");
304→ }
305→ f2(1, 3);
306→}
307→
308→function test_to_primitive()
309→{
310→ var obj;
311→ obj = { x : "abc", y: 1234 };
312→ obj.toString = function () { return this.x; };
313→ obj.valueOf = function () { return this.y; };
314→ assert(obj + "", "1234");
315→ assert(obj * 1, 1234);
316→}
317→
318→function test_labels()
319→{
320→ do x: { break x; } while(0);
321→ if (1)
322→ x: { break x; }
323→ else
324→ x: { break x; }
325→ while (0) x: { break x; };
326→}
327→
328→function test_labels2()
329→{
330→ while (1) label: break
331→ var i = 0
332→ while (i < 3) label: {
333→ if (i > 0)
334→ break
335→ i++
336→ }
337→ assert(i == 1)
338→ for (;;) label: break
339→ for (i = 0; i < 3; i++) label: {
340→ if (i > 0)
341→ break
342→ }
343→ assert(i == 1)
344→}
345→
346→test_op1();
347→test_cvt();
348→test_eq();
349→test_inc_dec();
350→test_op2();
351→test_prototype();
352→test_arguments();
353→test_to_primitive();
354→test_labels();
355→test_labels2();
356→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see there's a lot of tests. The error is "undefined is not a function". This likely happens when we try to call something that's undefined. Let me find out where exactly this happens by running a smaller test:
uv run python -c "
from mquickjs_python import JSContext
# Run individual test functions to find the failure
source = open('tests/test_language.js').read()
# Execute just the helper functions
helpers = '''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === 'object') {
if (o === null)
return 'null';
if (o && o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (actual === expected) {
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === 'number') {
if (isNaN(actual) && isNaN(expected))
return true;
}
if (typeof actual === 'object') {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor
&& actual.toString() === expected.toString())
return;
}
}
throw_error(\"assertion failed: got \" +
get_full_type(actual) + \":|\" + actual + \"|, expected \" +
get_full_type(expected) + \":|\" + expected + \"|\" +
(message ? \" (\" + message + \")\" : \"\"));
}
'''
ctx = JSContext(time_limit=2.0)
ctx.eval(helpers)
print('Helpers loaded')
# Test individual functions
tests = [
('test_op1', '''
function test_op1()
{
var r, a;
r = 1 + 2;
assert(r, 3);
r = 2 ** 8;
assert(r, 256, \"2 ** 8 === 256\");
}
test_op1();
'''),
]
for name, test in tests:
try:
ctx.eval(test)
print(f'{name}: PASSED')
except Exception as e:
print(f'{name}: FAILED - {type(e).__name__}: {e}')
" 2>&1Exit code 1
Traceback (most recent call last):
File "<string>", line 52, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 622, in eval
ast = parser.parse()
^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 114, in parse
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 163, in _parse_statement
return self._parse_function_declaration()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 391, in _parse_function_declaration
body = self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 133, in _parse_statement
return self._parse_if_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 210, in _parse_if_statement
consequent = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 127, in _parse_statement
return self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 133, in _parse_statement
return self._parse_if_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 210, in _parse_if_statement
consequent = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 127, in _parse_statement
return self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 133, in _parse_statement
return self._parse_if_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 208, in _parse_if_statement
test = self._parse_expression()
^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 421, in _parse_expression
expr = self._parse_assignment_expression(exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 435, in _parse_assignment_expression
if self._is_arrow_function_single_param():
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 466, in _is_arrow_function_single_param
self._advance() # identifier
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 54, in _advance
self.current = self.lexer.next_token()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/lexer.py", line 388, in next_token
raise JSSyntaxError(f"Unexpected character: {ch!r}", line, column)
mquickjs_python.errors.JSSyntaxError: SyntaxError: Unexpected character: '\\'I see there's an issue with escape sequences in the string. Let me try a different approach:
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext(time_limit=2.0)
# Run the test file step by step - first just the helpers
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
if (arguments.length == 1) expected = true;
if (actual === expected) return;
if (typeof actual === \"number\" && typeof expected === \"number\" && isNaN(actual) && isNaN(expected)) return;
throw_error(\"assertion failed: \" + actual + \" !== \" + expected + (message ? \" (\" + message + \")\" : \"\"));
}
''')
print('Helpers loaded')
# Test exponentiation
try:
result = ctx.eval('2 ** 8')
print(f'2 ** 8 = {result}')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1Good, exponentiation works. Let me now just run the test_language.js to find exactly where the error occurs:
uv run python -c "
from mquickjs_python import JSContext
import traceback
source = open('tests/test_language.js').read()
# Add some tracing
source = source.replace('test_op1();', 'console.log(\"Running test_op1\"); test_op1(); console.log(\"Done test_op1\");')
source = source.replace('test_cvt();', 'console.log(\"Running test_cvt\"); test_cvt(); console.log(\"Done test_cvt\");')
source = source.replace('test_eq();', 'console.log(\"Running test_eq\"); test_eq(); console.log(\"Done test_eq\");')
source = source.replace('test_inc_dec();', 'console.log(\"Running test_inc_dec\"); test_inc_dec(); console.log(\"Done test_inc_dec\");')
source = source.replace('test_op2();', 'console.log(\"Running test_op2\"); test_op2(); console.log(\"Done test_op2\");')
source = source.replace('test_prototype();', 'console.log(\"Running test_prototype\"); test_prototype(); console.log(\"Done test_prototype\");')
source = source.replace('test_arguments();', 'console.log(\"Running test_arguments\"); test_arguments(); console.log(\"Done test_arguments\");')
source = source.replace('test_to_primitive();', 'console.log(\"Running test_to_primitive\"); test_to_primitive(); console.log(\"Done test_to_primitive\");')
source = source.replace('test_labels();', 'console.log(\"Running test_labels\"); test_labels(); console.log(\"Done test_labels\");')
source = source.replace('test_labels2();', 'console.log(\"Running test_labels2\"); test_labels2(); console.log(\"Done test_labels2\");')
ctx = JSContext(time_limit=5.0)
try:
ctx.eval(source)
print('ALL PASSED')
except Exception as e:
traceback.print_exc()
" 2>&1Running test_op1
Done test_op1
Running test_cvt
Done test_cvt
Running test_eq
Done test_eq
Running test_inc_dec
Done test_inc_dec
Running test_op2
Traceback (most recent call last):
File "<string>", line 21, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 634, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 557, in _execute_opcode
self._call_method(method, this_val, args)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1563, in _call_method
raise JSTypeError(f"{method} is not a function")
mquickjs_python.errors.JSTypeError: TypeError: undefined is not a functionThe error happens in test_op2. Let me look at test_op2 and find which line is causing the error:
uv run python -c "
from mquickjs_python import JSContext
import traceback
ctx = JSContext(time_limit=5.0)
# Setup helper
ctx.eval('''
function assert(actual, expected, message) {
if (arguments.length == 1) expected = true;
if (actual === expected) return;
if (typeof actual === \"number\" && typeof expected === \"number\" && isNaN(actual) && isNaN(expected)) return;
throw Error(\"assertion failed: \" + actual + \" !== \" + expected + (message ? \" (\" + message + \")\" : \"\"));
}
function F(x)
{
this.x = x;
}
''')
# Test various lines from test_op2
tests = [
('new Object', 'var a = new Object; a.x = 1; assert(a.x, 1, \"new\");'),
('new F(2)', 'var b = new F(2); assert(b.x, 2, \"new\");'),
('instanceof F', 'var b = new F(2); assert((b instanceof F), true, \"instanceof F\");'),
('in operator', 'var a = {x : 2}; assert((\"x\" in a), true, \"in\");'),
('instanceof Object', 'var a = {}; assert((a instanceof Object), true, \"instanceof Object\");'),
('instanceof String', 'var a = {}; assert((a instanceof String), false, \"instanceof String\");'),
('typeof 1', 'assert((typeof 1), \"number\", \"typeof\");'),
('typeof Object', 'assert((typeof Object), \"function\", \"typeof\");'),
('typeof null', 'assert((typeof null), \"object\", \"typeof\");'),
('typeof unknown_var', 'assert((typeof unknown_var), \"undefined\", \"typeof\");'),
('delete', 'var a = {x: 1, y: 1}; assert((delete a.x), true, \"delete\");'),
('if keyword as prop', 'var a = {x: 1, if: 2}; assert(a.if, 2);'),
('__proto__ in literal', 'var a = {x: 1, y: 2, __proto__: { z: 3 }}; assert(a.x, 1);'),
('Object.getPrototypeOf', 'var a = {x: 1, y: 2, __proto__: { z: 3 }}; assert(Object.getPrototypeOf(a).z, 3);'),
]
for name, test in tests:
try:
ctx.eval(test)
print(f'{name}: PASSED')
except Exception as e:
print(f'{name}: FAILED - {e}')
break
" 2>&1new Object: PASSED new F(2): PASSED instanceof F: PASSED in operator: PASSED instanceof Object: PASSED instanceof String: PASSED typeof 1: PASSED typeof Object: PASSED typeof null: PASSED typeof unknown_var: PASSED delete: PASSED if keyword as prop: PASSED __proto__ in literal: PASSED Object.getPrototypeOf: FAILED - TypeError: undefined is not a function
Object.getPrototypeOf is not defined. I need to add it. Let me update the todo list and implement Object.getPrototypeOf:
Todos have been modified successfully. Ensure that you continue to use the todo list to track your progress. Please proceed with the current tasks if applicable
Now let me find where Object is created and add the getPrototypeOf method. Let me search for _create_object_constructor:
{
"-A": 60,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"pattern": "def _create_object_constructor"
}83: def _create_object_constructor(self) -> JSCallableObject:
84- """Create the Object constructor with static methods."""
85- # Create Object.prototype first
86- object_prototype = JSObject()
87-
88- # Constructor function - new Object() creates empty object
89- def object_constructor(*args):
90- obj = JSObject()
91- obj._prototype = object_prototype
92- return obj
93-
94- # Create a callable object that acts as constructor
95- obj_constructor = JSCallableObject(object_constructor)
96- obj_constructor._prototype = object_prototype
97- object_prototype.set("constructor", obj_constructor)
98-
99- # Store for other constructors to use
100- self._object_prototype = object_prototype
101-
102- def keys_fn(*args):
103- obj = args[0] if args else UNDEFINED
104- if not isinstance(obj, JSObject):
105- return JSArray()
106- arr = JSArray()
107- arr._elements = list(obj.keys())
108- return arr
109-
110- def values_fn(*args):
111- obj = args[0] if args else UNDEFINED
112- if not isinstance(obj, JSObject):
113- return JSArray()
114- arr = JSArray()
115- arr._elements = [obj.get(k) for k in obj.keys()]
116- return arr
117-
118- def entries_fn(*args):
119- obj = args[0] if args else UNDEFINED
120- if not isinstance(obj, JSObject):
121- return JSArray()
122- arr = JSArray()
123- arr._elements = []
124- for k in obj.keys():
125- entry = JSArray()
126- entry._elements = [k, obj.get(k)]
127- arr._elements.append(entry)
128- return arr
129-
130- def assign_fn(*args):
131- if not args:
132- return JSObject()
133- target = args[0]
134- if not isinstance(target, JSObject):
135- return target
136- for i in range(1, len(args)):
137- source = args[i]
138- if isinstance(source, JSObject):
139- for k in source.keys():
140- target.set(k, source.get(k))
141- return target
142-
143- obj_constructor.set("keys", keys_fn){
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/context.py",
"limit": 40,
"offset": 140
} 140→ target.set(k, source.get(k))
141→ return target
142→
143→ obj_constructor.set("keys", keys_fn)
144→ obj_constructor.set("values", values_fn)
145→ obj_constructor.set("entries", entries_fn)
146→ obj_constructor.set("assign", assign_fn)
147→
148→ return obj_constructor
149→
150→ def _create_array_constructor(self) -> JSCallableObject:
151→ """Create the Array constructor with static methods."""
152→ # Create Array.prototype (inherits from Object.prototype)
153→ array_prototype = JSArray()
154→ array_prototype._prototype = self._object_prototype
155→
156→ def array_constructor(*args):
157→ if len(args) == 1 and isinstance(args[0], (int, float)):
158→ arr = JSArray(int(args[0]))
159→ else:
160→ arr = JSArray()
161→ for arg in args:
162→ arr.push(arg)
163→ arr._prototype = array_prototype
164→ return arr
165→
166→ arr_constructor = JSCallableObject(array_constructor)
167→ arr_constructor._prototype = array_prototype
168→ array_prototype.set("constructor", arr_constructor)
169→
170→ # Store for other uses
171→ self._array_prototype = array_prototype
172→
173→ # Array.isArray()
174→ def is_array(*args):
175→ obj = args[0] if args else UNDEFINED
176→ return isinstance(obj, JSArray)
177→
178→ arr_constructor.set("isArray", is_array)
179→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
Good. I need to add Object.getPrototypeOf and Object.setPrototypeOf to the Object constructor. Let me add them before line 143:
obj_constructor.set("keys", keys_fn)
obj_constructor.set("values", values_fn)
obj_constructor.set("entries", entries_fn)
obj_constructor.set("assign", assign_fn)
return obj_constructor def get_prototype_of(*args):
obj = args[0] if args else UNDEFINED
if not isinstance(obj, JSObject):
return NULL
return getattr(obj, '_prototype', NULL) or NULL
def set_prototype_of(*args):
if len(args) < 2:
return UNDEFINED
obj, proto = args[0], args[1]
if not isinstance(obj, JSObject):
return obj
if proto is NULL or proto is None:
obj._prototype = None
elif isinstance(proto, JSObject):
obj._prototype = proto
return obj
obj_constructor.set("keys", keys_fn)
obj_constructor.set("values", values_fn)
obj_constructor.set("entries", entries_fn)
obj_constructor.set("assign", assign_fn)
obj_constructor.set("getPrototypeOf", get_prototype_of)
obj_constructor.set("setPrototypeOf", set_prototype_of)
return obj_constructorThe file /home/user/mquickjs-python/src/mquickjs_python/context.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
139→ for k in source.keys():
140→ target.set(k, source.get(k))
141→ return target
142→
143→ def get_prototype_of(*args):
144→ obj = args[0] if args else UNDEFINED
145→ if not isinstance(obj, JSObject):
146→ return NULL
147→ return getattr(obj, '_prototype', NULL) or NULL
148→
149→ def set_prototype_of(*args):
150→ if len(args) < 2:
151→ return UNDEFINED
152→ obj, proto = args[0], args[1]
153→ if not isinstance(obj, JSObject):
154→ return obj
155→ if proto is NULL or proto is None:
156→ obj._prototype = None
157→ elif isinstance(proto, JSObject):
158→ obj._prototype = proto
159→ return obj
160→
161→ obj_constructor.set("keys", keys_fn)
162→ obj_constructor.set("values", values_fn)
163→ obj_constructor.set("entries", entries_fn)
164→ obj_constructor.set("assign", assign_fn)
165→ obj_constructor.set("getPrototypeOf", get_prototype_of)
166→ obj_constructor.set("setPrototypeOf", set_prototype_of)
167→
168→ return obj_constructor
169→
170→ def _create_array_constructor(self) -> JSCallableObject:
171→ """Create the Array constructor with static methods."""
172→ # Create Array.prototype (inherits from Object.prototype)uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext(time_limit=2.0)
# Test Object.getPrototypeOf
result = ctx.eval('''
var a = {x: 1, y: 2, __proto__: { z: 3 }};
Object.getPrototypeOf(a).z
''')
print(f'Result: {result}')
" 2>&1The result is None, but it should be 3. The issue is likely that __proto__ in object literals isn't being handled. Let me check if __proto__ handling exists in the compiler/vm:
The result is None, not 3. The __proto__ in object literal isn't being handled. Let me check how object literals are compiled:
{
"-B": 3,
"-C": 20,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python",
"pattern": "BUILD_OBJECT"
}/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1073- self._emit(OpCode.THIS)
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1074-
src/mquickjs_python/compiler.py-1075- elif isinstance(node, ArrayExpression):
src/mquickjs_python/compiler.py-1076- for elem in node.elements:
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1077- self._compile_expression(elem)
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1078- self._emit(OpCode.BUILD_ARRAY, len(node.elements))
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1079-
src/mquickjs_python/compiler.py-1080- elif isinstance(node, ObjectExpression):
src/mquickjs_python/compiler.py-1081- for prop in node.properties:
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1082- # Key
src/mquickjs_python/compiler.py-1083- if isinstance(prop.key, Identifier):
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1084- idx = self._add_constant(prop.key.name)
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1085- self._emit(OpCode.LOAD_CONST, idx)
src/mquickjs_python/compiler.py-1086- else:
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1087- self._compile_expression(prop.key)
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1088- # Kind (for getters/setters)
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1089- kind_idx = self._add_constant(prop.kind)
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1090- self._emit(OpCode.LOAD_CONST, kind_idx)
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1091- # Value
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1092- self._compile_expression(prop.value)
src/mquickjs_python/compiler.py:1093: self._emit(OpCode.BUILD_OBJECT, len(node.properties))
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1094-
src/mquickjs_python/compiler.py-1095- elif isinstance(node, UnaryExpression):
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1096- # Special case for typeof with identifier - must not throw for undeclared vars
src/mquickjs_python/compiler.py-1097- if node.operator == "typeof" and isinstance(node.argument, Identifier):
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1098- name = node.argument.name
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1099- # Check for local, cell, or closure vars first
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1100- local_slot = self._get_local(name)
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1101- cell_slot = self._get_cell_var(name)
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1102- closure_slot = self._get_free_var(name)
src/mquickjs_python/compiler.py-1103- if local_slot is not None:
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1104- self._emit(OpCode.LOAD_LOCAL, local_slot)
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1105- self._emit(OpCode.TYPEOF)
src/mquickjs_python/compiler.py-1106- elif cell_slot is not None:
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1107- self._emit(OpCode.LOAD_CELL, cell_slot)
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1108- self._emit(OpCode.TYPEOF)
src/mquickjs_python/compiler.py-1109- elif closure_slot is not None:
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1110- self._emit(OpCode.LOAD_CLOSURE, closure_slot)
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1111- self._emit(OpCode.TYPEOF)
src/mquickjs_python/compiler.py-1112- else:
/home/user/mquickjs-python/src/mquickjs_python/compiler.py-1113- # Use TYPEOF_NAME for global lookup - won't throw if undefined
--
/home/user/mquickjs-python/src/mquickjs_python/vm.py-138- # End of function
/home/user/mquickjs-python/src/mquickjs_python/vm.py-139- return self.stack.pop() if self.stack else UNDEFINED
/home/user/mquickjs-python/src/mquickjs_python/vm.py-140-
/home/user/mquickjs-python/src/mquickjs_python/vm.py-141- op = OpCode(bytecode[frame.ip])
/home/user/mquickjs-python/src/mquickjs_python/vm.py-142- frame.ip += 1
/home/user/mquickjs-python/src/mquickjs_python/vm.py-143-
/home/user/mquickjs-python/src/mquickjs_python/vm.py-144- # Get argument if needed
/home/user/mquickjs-python/src/mquickjs_python/vm.py-145- arg = None
src/mquickjs_python/vm.py-146- if op in (OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE, OpCode.TRY_START):
/home/user/mquickjs-python/src/mquickjs_python/vm.py-147- # 16-bit little-endian argument for jumps
/home/user/mquickjs-python/src/mquickjs_python/vm.py-148- low = bytecode[frame.ip]
/home/user/mquickjs-python/src/mquickjs_python/vm.py-149- high = bytecode[frame.ip + 1]
/home/user/mquickjs-python/src/mquickjs_python/vm.py-150- arg = low | (high << 8)
/home/user/mquickjs-python/src/mquickjs_python/vm.py-151- frame.ip += 2
/home/user/mquickjs-python/src/mquickjs_python/vm.py-152- elif op in (
/home/user/mquickjs-python/src/mquickjs_python/vm.py-153- OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME,
/home/user/mquickjs-python/src/mquickjs_python/vm.py-154- OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL,
/home/user/mquickjs-python/src/mquickjs_python/vm.py-155- OpCode.LOAD_CLOSURE, OpCode.STORE_CLOSURE,
/home/user/mquickjs-python/src/mquickjs_python/vm.py-156- OpCode.LOAD_CELL, OpCode.STORE_CELL,
/home/user/mquickjs-python/src/mquickjs_python/vm.py-157- OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
src/mquickjs_python/vm.py:158: OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
/home/user/mquickjs-python/src/mquickjs_python/vm.py-159- OpCode.MAKE_CLOSURE, OpCode.TYPEOF_NAME,
src/mquickjs_python/vm.py-160- ):
/home/user/mquickjs-python/src/mquickjs_python/vm.py-161- arg = bytecode[frame.ip]
/home/user/mquickjs-python/src/mquickjs_python/vm.py-162- frame.ip += 1
/home/user/mquickjs-python/src/mquickjs_python/vm.py-163-
/home/user/mquickjs-python/src/mquickjs_python/vm.py-164- # Execute opcode
/home/user/mquickjs-python/src/mquickjs_python/vm.py-165- self._execute_opcode(op, arg, frame)
/home/user/mquickjs-python/src/mquickjs_python/vm.py-166-
/home/user/mquickjs-python/src/mquickjs_python/vm.py-167- # Check if frame was popped (return)
src/mquickjs_python/vm.py-168- if not self.call_stack:
/home/user/mquickjs-python/src/mquickjs_python/vm.py-169- break
/home/user/mquickjs-python/src/mquickjs_python/vm.py-170-
/home/user/mquickjs-python/src/mquickjs_python/vm.py-171- return self.stack.pop() if self.stack else UNDEFINED
/home/user/mquickjs-python/src/mquickjs_python/vm.py-172-
src/mquickjs_python/vm.py-173- def _execute_opcode(self, op: OpCode, arg: Optional[int], frame: CallFrame) -> None:
/home/user/mquickjs-python/src/mquickjs_python/vm.py-174- """Execute a single opcode."""
/home/user/mquickjs-python/src/mquickjs_python/vm.py-175-
/home/user/mquickjs-python/src/mquickjs_python/vm.py-176- # Stack operations
src/mquickjs_python/vm.py-177- if op == OpCode.POP:
src/mquickjs_python/vm.py-178- if self.stack:
--
/home/user/mquickjs-python/src/mquickjs_python/vm.py-282-
src/mquickjs_python/vm.py-283- elif op == OpCode.DELETE_PROP:
/home/user/mquickjs-python/src/mquickjs_python/vm.py-284- key = self.stack.pop()
/home/user/mquickjs-python/src/mquickjs_python/vm.py-285- obj = self.stack.pop()
/home/user/mquickjs-python/src/mquickjs_python/vm.py-286- result = self._delete_property(obj, key)
/home/user/mquickjs-python/src/mquickjs_python/vm.py-287- self.stack.append(result)
/home/user/mquickjs-python/src/mquickjs_python/vm.py-288-
/home/user/mquickjs-python/src/mquickjs_python/vm.py-289- # Arrays/Objects
src/mquickjs_python/vm.py-290- elif op == OpCode.BUILD_ARRAY:
/home/user/mquickjs-python/src/mquickjs_python/vm.py-291- elements = []
src/mquickjs_python/vm.py-292- for _ in range(arg):
/home/user/mquickjs-python/src/mquickjs_python/vm.py-293- elements.insert(0, self.stack.pop())
/home/user/mquickjs-python/src/mquickjs_python/vm.py-294- arr = JSArray()
/home/user/mquickjs-python/src/mquickjs_python/vm.py-295- arr._elements = elements
/home/user/mquickjs-python/src/mquickjs_python/vm.py-296- # Set prototype from Array constructor
/home/user/mquickjs-python/src/mquickjs_python/vm.py-297- array_constructor = self.globals.get("Array")
src/mquickjs_python/vm.py-298- if array_constructor and hasattr(array_constructor, '_prototype'):
/home/user/mquickjs-python/src/mquickjs_python/vm.py-299- arr._prototype = array_constructor._prototype
/home/user/mquickjs-python/src/mquickjs_python/vm.py-300- self.stack.append(arr)
/home/user/mquickjs-python/src/mquickjs_python/vm.py-301-
src/mquickjs_python/vm.py:302: elif op == OpCode.BUILD_OBJECT:
/home/user/mquickjs-python/src/mquickjs_python/vm.py-303- obj = JSObject()
/home/user/mquickjs-python/src/mquickjs_python/vm.py-304- # Set prototype from Object constructor
/home/user/mquickjs-python/src/mquickjs_python/vm.py-305- object_constructor = self.globals.get("Object")
src/mquickjs_python/vm.py-306- if object_constructor and hasattr(object_constructor, '_prototype'):
/home/user/mquickjs-python/src/mquickjs_python/vm.py-307- obj._prototype = object_constructor._prototype
/home/user/mquickjs-python/src/mquickjs_python/vm.py-308- props = []
src/mquickjs_python/vm.py-309- for _ in range(arg):
/home/user/mquickjs-python/src/mquickjs_python/vm.py-310- value = self.stack.pop()
/home/user/mquickjs-python/src/mquickjs_python/vm.py-311- kind = self.stack.pop()
/home/user/mquickjs-python/src/mquickjs_python/vm.py-312- key = self.stack.pop()
/home/user/mquickjs-python/src/mquickjs_python/vm.py-313- props.insert(0, (key, kind, value))
src/mquickjs_python/vm.py-314- for key, kind, value in props:
/home/user/mquickjs-python/src/mquickjs_python/vm.py-315- key_str = to_string(key) if not isinstance(key, str) else key
src/mquickjs_python/vm.py-316- if kind == "get":
/home/user/mquickjs-python/src/mquickjs_python/vm.py-317- obj.define_getter(key_str, value)
src/mquickjs_python/vm.py-318- elif kind == "set":
/home/user/mquickjs-python/src/mquickjs_python/vm.py-319- obj.define_setter(key_str, value)
src/mquickjs_python/vm.py-320- else:
/home/user/mquickjs-python/src/mquickjs_python/vm.py-321- obj.set(key_str, value)
/home/user/mquickjs-python/src/mquickjs_python/vm.py-322- self.stack.append(obj)
--
src/mquickjs_python/vm.py-1583- if len(self.stack) > stack_len:
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1584- return self.stack.pop()
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1585- return UNDEFINED
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1586-
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1587- op = OpCode(bytecode[frame.ip])
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1588- frame.ip += 1
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1589-
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1590- # Get argument if needed
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1591- arg = None
src/mquickjs_python/vm.py-1592- if op in (OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE, OpCode.TRY_START):
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1593- low = bytecode[frame.ip]
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1594- high = bytecode[frame.ip + 1]
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1595- arg = low | (high << 8)
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1596- frame.ip += 2
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1597- elif op in (
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1598- OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME,
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1599- OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL,
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1600- OpCode.LOAD_CLOSURE, OpCode.STORE_CLOSURE,
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1601- OpCode.LOAD_CELL, OpCode.STORE_CELL,
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1602- OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
src/mquickjs_python/vm.py:1603: OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1604- OpCode.MAKE_CLOSURE,
src/mquickjs_python/vm.py-1605- ):
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1606- arg = bytecode[frame.ip]
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1607- frame.ip += 1
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1608-
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1609- self._execute_opcode(op, arg, frame)
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1610-
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1611- # Get result from stack
src/mquickjs_python/vm.py-1612- if len(self.stack) > stack_len:
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1613- return self.stack.pop()
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1614- return UNDEFINED
src/mquickjs_python/vm.py-1615- elif callable(callback):
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1616- result = callback(*args)
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1617- return result if result is not None else UNDEFINED
src/mquickjs_python/vm.py-1618- else:
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1619- raise JSTypeError(f"{callback} is not a function")
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1620-
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1621- def _invoke_js_function(
/home/user/mquickjs-python/src/mquickjs_python/vm.py-1622- self,
src/mquickjs_python/vm.py-1623- func: JSFunction,
--
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-17- # Constants
src/mquickjs_python/opcodes.py-18- LOAD_CONST = auto() # Load constant from pool: arg = constant index
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-19- LOAD_UNDEFINED = auto()
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-20- LOAD_NULL = auto()
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-21- LOAD_TRUE = auto()
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-22- LOAD_FALSE = auto()
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-23-
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-24- # Variables
src/mquickjs_python/opcodes.py-25- LOAD_NAME = auto() # Load variable by name: arg = name index
src/mquickjs_python/opcodes.py-26- STORE_NAME = auto() # Store variable by name: arg = name index
src/mquickjs_python/opcodes.py-27- LOAD_LOCAL = auto() # Load local variable: arg = slot index
src/mquickjs_python/opcodes.py-28- STORE_LOCAL = auto() # Store local variable: arg = slot index
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-29-
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-30- # Properties
src/mquickjs_python/opcodes.py-31- GET_PROP = auto() # Get property: obj, key -> value
src/mquickjs_python/opcodes.py-32- SET_PROP = auto() # Set property: obj, key, value -> value
src/mquickjs_python/opcodes.py-33- DELETE_PROP = auto() # Delete property: obj, key -> bool
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-34-
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-35- # Arrays/Objects
src/mquickjs_python/opcodes.py-36- BUILD_ARRAY = auto() # Build array from stack: arg = element count
src/mquickjs_python/opcodes.py:37: BUILD_OBJECT = auto() # Build object from stack: arg = property count
src/mquickjs_python/opcodes.py-38- BUILD_REGEX = auto() # Build regex from constant: constant index points to (pattern, flags) tuple
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-39-
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-40- # Arithmetic
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-41- ADD = auto()
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-42- SUB = auto()
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-43- MUL = auto()
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-44- DIV = auto()
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-45- MOD = auto()
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-46- POW = auto()
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-47- NEG = auto() # Unary minus
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-48- POS = auto() # Unary plus
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-49-
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-50- # Bitwise
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-51- BAND = auto() # Bitwise AND
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-52- BOR = auto() # Bitwise OR
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-53- BXOR = auto() # Bitwise XOR
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-54- BNOT = auto() # Bitwise NOT
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-55- SHL = auto() # Shift left
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-56- SHR = auto() # Shift right (signed)
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-57- USHR = auto() # Shift right (unsigned)
--
src/mquickjs_python/opcodes.py-113- MAKE_CLOSURE = auto() # Create closure: arg = function index
src/mquickjs_python/opcodes.py-114- LOAD_CLOSURE = auto() # Load from closure: arg = closure slot (for inner function)
src/mquickjs_python/opcodes.py-115- STORE_CLOSURE = auto() # Store to closure: arg = closure slot (for inner function)
src/mquickjs_python/opcodes.py-116- LOAD_CELL = auto() # Load from cell: arg = cell slot (for outer function)
src/mquickjs_python/opcodes.py-117- STORE_CELL = auto() # Store to cell: arg = cell slot (for outer function)
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-118-
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-119-
src/mquickjs_python/opcodes.py-120-def disassemble(bytecode: bytes, constants: list) -> str:
/home/user/mquickjs-python/src/mquickjs_python/opcodes.py-121- """Disassemble bytecode for debugging.
... [31 lines truncated] ...I see the BUILD_OBJECT handler. The issue is that when the property key is __proto__, we should set the object's _prototype instead of setting it as a regular property. Let me update the BUILD_OBJECT handler:
I see the issue. The __proto__ in object literals should set the prototype, not be a regular property. Let me update BUILD_OBJECT:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 30,
"offset": 300
} 300→ self.stack.append(arr)
301→
302→ elif op == OpCode.BUILD_OBJECT:
303→ obj = JSObject()
304→ # Set prototype from Object constructor
305→ object_constructor = self.globals.get("Object")
306→ if object_constructor and hasattr(object_constructor, '_prototype'):
307→ obj._prototype = object_constructor._prototype
308→ props = []
309→ for _ in range(arg):
310→ value = self.stack.pop()
311→ kind = self.stack.pop()
312→ key = self.stack.pop()
313→ props.insert(0, (key, kind, value))
314→ for key, kind, value in props:
315→ key_str = to_string(key) if not isinstance(key, str) else key
316→ if kind == "get":
317→ obj.define_getter(key_str, value)
318→ elif kind == "set":
319→ obj.define_setter(key_str, value)
320→ else:
321→ obj.set(key_str, value)
322→ self.stack.append(obj)
323→
324→ elif op == OpCode.BUILD_REGEX:
325→ pattern, flags = frame.func.constants[arg]
326→ regex = JSRegExp(pattern, flags)
327→ self.stack.append(regex)
328→
329→ # Arithmetic
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I need to handle __proto__ specially in BUILD_OBJECT. When the key is __proto__ and kind is "init", we should set the prototype instead of adding it as a property:
for key, kind, value in props:
key_str = to_string(key) if not isinstance(key, str) else key
if kind == "get":
obj.define_getter(key_str, value)
elif kind == "set":
obj.define_setter(key_str, value)
else:
obj.set(key_str, value)
self.stack.append(obj) for key, kind, value in props:
key_str = to_string(key) if not isinstance(key, str) else key
if kind == "get":
obj.define_getter(key_str, value)
elif kind == "set":
obj.define_setter(key_str, value)
elif key_str == "__proto__" and kind == "init":
# __proto__ in object literal sets the prototype
if value is NULL or value is None:
obj._prototype = None
elif isinstance(value, JSObject):
obj._prototype = value
else:
obj.set(key_str, value)
self.stack.append(obj)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 310→ value = self.stack.pop() 311→ kind = self.stack.pop() 312→ key = self.stack.pop() 313→ props.insert(0, (key, kind, value)) 314→ for key, kind, value in props: 315→ key_str = to_string(key) if not isinstance(key, str) else key 316→ if kind == "get": 317→ obj.define_getter(key_str, value) 318→ elif kind == "set": 319→ obj.define_setter(key_str, value) 320→ elif key_str == "__proto__" and kind == "init": 321→ # __proto__ in object literal sets the prototype 322→ if value is NULL or value is None: 323→ obj._prototype = None 324→ elif isinstance(value, JSObject): 325→ obj._prototype = value 326→ else: 327→ obj.set(key_str, value) 328→ self.stack.append(obj) 329→ 330→ elif op == OpCode.BUILD_REGEX: 331→ pattern, flags = frame.func.constants[arg] 332→ regex = JSRegExp(pattern, flags)
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext(time_limit=2.0)
# Test Object.getPrototypeOf
result = ctx.eval('''
var a = {x: 1, y: 2, __proto__: { z: 3 }};
Object.getPrototypeOf(a).z
''')
print(f'Result: {result}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
import traceback
source = open('tests/test_language.js').read()
# Add some tracing
source = source.replace('test_op1();', 'console.log(\"Running test_op1\"); test_op1(); console.log(\"Done test_op1\");')
source = source.replace('test_cvt();', 'console.log(\"Running test_cvt\"); test_cvt(); console.log(\"Done test_cvt\");')
source = source.replace('test_eq();', 'console.log(\"Running test_eq\"); test_eq(); console.log(\"Done test_eq\");')
source = source.replace('test_inc_dec();', 'console.log(\"Running test_inc_dec\"); test_inc_dec(); console.log(\"Done test_inc_dec\");')
source = source.replace('test_op2();', 'console.log(\"Running test_op2\"); test_op2(); console.log(\"Done test_op2\");')
source = source.replace('test_prototype();', 'console.log(\"Running test_prototype\"); test_prototype(); console.log(\"Done test_prototype\");')
source = source.replace('test_arguments();', 'console.log(\"Running test_arguments\"); test_arguments(); console.log(\"Done test_arguments\");')
source = source.replace('test_to_primitive();', 'console.log(\"Running test_to_primitive\"); test_to_primitive(); console.log(\"Done test_to_primitive\");')
source = source.replace('test_labels();', 'console.log(\"Running test_labels\"); test_labels(); console.log(\"Done test_labels\");')
source = source.replace('test_labels2();', 'console.log(\"Running test_labels2\"); test_labels2(); console.log(\"Done test_labels2\");')
ctx = JSContext(time_limit=5.0)
try:
ctx.eval(source)
print('ALL PASSED')
except Exception as e:
traceback.print_exc()
" 2>&1Running test_op1
Done test_op1
Running test_cvt
Done test_cvt
Running test_eq
Done test_eq
Running test_inc_dec
Done test_inc_dec
Running test_op2
Traceback (most recent call last):
File "<string>", line 21, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 553, in _execute_opcode
self._call_function(arg, None)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1559, in _call_function
raise JSTypeError(f"{callee} is not a function")
mquickjs_python.errors.JSTypeError: TypeError: undefined is not a functionThere's still an error in test_op2. Let me continue testing line by line from where we left off:
uv run python -c "
from mquickjs_python import JSContext
import traceback
ctx = JSContext(time_limit=5.0)
# Setup helper
ctx.eval('''
function assert(actual, expected, message) {
if (arguments.length == 1) expected = true;
if (actual === expected) return;
if (typeof actual === \"number\" && typeof expected === \"number\" && isNaN(actual) && isNaN(expected)) return;
throw Error(\"assertion failed: \" + actual + \" !== \" + expected + (message ? \" (\" + message + \")\" : \"\"));
}
function F(x)
{
this.x = x;
}
''')
# Test more lines from test_op2
tests = [
('getter/setter', '''
var b = 2;
var a = {get x() { return b; }, set x(v) { b = v; }, f(v) { return v + 1 },
set: 10, get: 11 };
assert(a.x, 2);
a.x = 3;
assert(a.x, 3);
assert(a.f(3), 4);
assert(a.set, 10);
assert(a.get, 11);
'''),
('method set/get as names', '''
var a = { set() { return 1; }, get() { return 2; }}
assert(a.set(), 1);
assert(a.get(), 2);
'''),
]
for name, test in tests:
try:
ctx.eval(test)
print(f'{name}: PASSED')
except Exception as e:
print(f'{name}: FAILED - {e}')
traceback.print_exc()
break
" 2>&1getter/setter: FAILED - TypeError: undefined is not a function
Traceback (most recent call last):
File "<string>", line 44, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 553, in _execute_opcode
self._call_function(arg, None)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1559, in _call_function
raise JSTypeError(f"{callee} is not a function")
mquickjs_python.errors.JSTypeError: TypeError: undefined is not a functionThe issue is with the shorthand method syntax f(v) { return v + 1 }. This is ES6 method shorthand. Let me see if it's parsing correctly first:
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test shorthand method
result = ctx.eval('''
var a = {
f(v) { return v + 1; }
};
a.f(3)
''')
print(f'Result: {result}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test the full object
result = ctx.eval('''
var b = 2;
var a = {get x() { return b; }, set x(v) { b = v; }, f(v) { return v + 1 },
set: 10, get: 11 };
a.x
''')
print(f'a.x (getter): {result}')
result = ctx.eval('a.x = 3; a.x')
print(f'a.x after setter: {result}')
result = ctx.eval('a.f(3)')
print(f'a.f(3): {result}')
" 2>&1Interesting, all these tests work individually. Let me check if there's something wrong with the assert function in the combined test:
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test the full object with assert
result = ctx.eval('''
function assert(actual, expected, message) {
if (actual === expected) return;
throw Error(\"assertion failed: \" + actual + \" !== \" + expected + (message ? \" (\" + message + \")\" : \"\"));
}
var b = 2;
var a = {get x() { return b; }, set x(v) { b = v; }, f(v) { return v + 1 },
set: 10, get: 11 };
assert(a.x, 2);
a.x = 3;
assert(a.x, 3);
assert(a.f(3), 4);
assert(a.set, 10);
assert(a.get, 11);
\"OK\"
''')
print(f'Result: {result}')
" 2>&1Exit code 1
Traceback (most recent call last):
File "<string>", line 7, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 553, in _execute_opcode
self._call_function(arg, None)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1559, in _call_function
raise JSTypeError(f"{callee} is not a function")
mquickjs_python.errors.JSTypeError: TypeError: undefined is not a functionInteresting! The problem appears when assert is defined in the same code. Let me simplify step by step:
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test step by step
ctx.eval('''
function assert(actual, expected, message) {
if (actual === expected) return;
throw Error(\"assertion failed\");
}
''')
ctx.eval('''
var b = 2;
var a = {get x() { return b; }, set x(v) { b = v; }, f(v) { return v + 1 },
set: 10, get: 11 };
''')
print('Testing a.x...')
ctx.eval('assert(a.x, 2);')
print('OK')
print('Setting a.x = 3...')
ctx.eval('a.x = 3;')
print('OK')
print('Testing a.x after set...')
ctx.eval('assert(a.x, 3);')
print('OK')
print('Testing a.f(3)...')
result = ctx.eval('a.f(3)')
print(f'a.f(3) = {result}')
ctx.eval('assert(a.f(3), 4);')
print('OK')
print('Testing a.set...')
ctx.eval('assert(a.set, 10);')
print('OK')
print('Testing a.get...')
ctx.eval('assert(a.get, 11);')
print('OK')
" 2>&1Exit code 1
Testing a.x...
Traceback (most recent call last):
File "<string>", line 21, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 553, in _execute_opcode
self._call_function(arg, None)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1559, in _call_function
raise JSTypeError(f"{callee} is not a function")
mquickjs_python.errors.JSTypeError: TypeError: undefined is not a functionuv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Check a.x
ctx.eval('''
var b = 2;
var a = {get x() { return b; }, set x(v) { b = v; }};
''')
print(f'a.x = {ctx.eval(\"a.x\")}')
# Now test with assert
ctx.eval('function assert(actual, expected) { if (actual !== expected) throw Error(\"fail\"); }')
# Test assert with a simple value
ctx.eval('assert(2, 2);')
print('assert(2, 2) passed')
# Now test with a.x
result = ctx.eval('a.x')
print(f'a.x for assert = {result}')
ctx.eval('assert(a.x, 2);')
print('assert(a.x, 2) passed')
" 2>&1Exit code 1
a.x = 2
assert(2, 2) passed
a.x for assert = 2
Traceback (most recent call last):
File "<string>", line 24, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 553, in _execute_opcode
self._call_function(arg, None)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1559, in _call_function
raise JSTypeError(f"{callee} is not a function")
mquickjs_python.errors.JSTypeError: TypeError: undefined is not a functionInteresting! a.x by itself works, but assert(a.x, 2) fails with "undefined is not a function". This suggests something is wrong when a getter is invoked as a function argument. Let me check how getters are being invoked when passed as arguments:
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
ctx.eval('''
var b = 2;
var a = {get x() { return b; }};
function test(val) { return val; }
''')
# Test passing getter result to function
result = ctx.eval('test(a.x)')
print(f'test(a.x) = {result}')
" 2>&1Exit code 1
Traceback (most recent call last):
File "<string>", line 13, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 553, in _execute_opcode
self._call_function(arg, None)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1559, in _call_function
raise JSTypeError(f"{callee} is not a function")
mquickjs_python.errors.JSTypeError: TypeError: undefined is not a functionSo the issue is when passing a.x (where x is a getter) as a function argument. Let me try a simpler case:
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
ctx.eval('''
var a = {get x() { return 42; }};
function test(val) { return val; }
''')
# Test passing getter result to function
result = ctx.eval('test(a.x)')
print(f'test(a.x) = {result}')
" 2>&1Exit code 1
Traceback (most recent call last):
File "<string>", line 12, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 553, in _execute_opcode
self._call_function(arg, None)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1559, in _call_function
raise JSTypeError(f"{callee} is not a function")
mquickjs_python.errors.JSTypeError: TypeError: undefined is not a functionThe issue is with getters used as function arguments. Let me check how the call expression is compiled:
uv run python -c "
from mquickjs_python.parser import Parser
from mquickjs_python.compiler import Compiler
from mquickjs_python.opcodes import disassemble
code = 'test(a.x)'
parser = Parser(code)
ast = parser.parse()
compiler = Compiler()
compiled = compiler.compile(ast)
print('Bytecode:')
print(disassemble(compiled.bytecode, compiled.constants))
" 2>&1Bytecode:
0: LOAD_NAME 0
2: LOAD_NAME 1
4: LOAD_CONST 2 ('x')
6: GET_PROP
7: CALL 1
9: RETURNThe bytecode looks correct: 1. LOAD_NAME 0 - loads "test" function 2. LOAD_NAME 1 - loads "a" object 3. LOAD_CONST 2 - loads "x" string 4. GET_PROP - gets a.x (should invoke getter) 5. CALL 1 - calls test with 1 argument
The issue must be in GET_PROP. Let me check how GET_PROP handles getters:
{
"-B": 2,
"-C": 30,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "GET_PROP"
}241-
242- elif op == OpCode.STORE_NAME:
243- name = frame.func.constants[arg]
244- self.globals[name] = self.stack[-1]
245-
246- elif op == OpCode.LOAD_CLOSURE:
247- if frame.closure_cells and arg < len(frame.closure_cells):
248- self.stack.append(frame.closure_cells[arg].value)
249- else:
250- raise JSReferenceError("Closure variable not found")
251-
252- elif op == OpCode.STORE_CLOSURE:
253- if frame.closure_cells and arg < len(frame.closure_cells):
254- frame.closure_cells[arg].value = self.stack[-1]
255- else:
256- raise JSReferenceError("Closure variable not found")
257-
258- elif op == OpCode.LOAD_CELL:
259- if frame.cell_storage and arg < len(frame.cell_storage):
260- self.stack.append(frame.cell_storage[arg].value)
261- else:
262- raise JSReferenceError("Cell variable not found")
263-
264- elif op == OpCode.STORE_CELL:
265- if frame.cell_storage and arg < len(frame.cell_storage):
266- frame.cell_storage[arg].value = self.stack[-1]
267- else:
268- raise JSReferenceError("Cell variable not found")
269-
270- # Properties
271: elif op == OpCode.GET_PROP:
272- key = self.stack.pop()
273- obj = self.stack.pop()
274- self.stack.append(self._get_property(obj, key))
275-
276- elif op == OpCode.SET_PROP:
277- value = self.stack.pop()
278- key = self.stack.pop()
279- obj = self.stack.pop()
280- self._set_property(obj, key, value)
281- self.stack.append(value)
282-
283- elif op == OpCode.DELETE_PROP:
284- key = self.stack.pop()
285- obj = self.stack.pop()
286- result = self._delete_property(obj, key)
287- self.stack.append(result)
288-
289- # Arrays/Objects
290- elif op == OpCode.BUILD_ARRAY:
291- elements = []
292- for _ in range(arg):
293- elements.insert(0, self.stack.pop())
294- arr = JSArray()
295- arr._elements = elements
296- # Set prototype from Array constructor
297- array_constructor = self.globals.get("Array")
298- if array_constructor and hasattr(array_constructor, '_prototype'):
299- arr._prototype = array_constructor._prototype
300- self.stack.append(arr)
301-The GET_PROP calls _get_property. Let me look at that method to see how it handles getters:
{
"-A": 50,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "def _get_property"
}809: def _get_property(self, obj: JSValue, key: JSValue) -> JSValue:
810- """Get property from object."""
811- if obj is UNDEFINED or obj is NULL:
812- raise JSTypeError(f"Cannot read property of {obj}")
813-
814- key_str = to_string(key) if not isinstance(key, str) else key
815-
816- if isinstance(obj, JSArray):
817- # Array index access
818- try:
819- idx = int(key_str)
820- if idx >= 0:
821- return obj.get_index(idx)
822- except ValueError:
823- pass
824- if key_str == "length":
825- return obj.length
826- # Built-in array methods
827- array_methods = [
828- "push", "pop", "shift", "unshift", "toString", "join",
829- "map", "filter", "reduce", "forEach", "indexOf", "lastIndexOf",
830- "find", "findIndex", "some", "every", "concat", "slice",
831- "reverse", "includes",
832- ]
833- if key_str in array_methods:
834- return self._make_array_method(obj, key_str)
835- return obj.get(key_str)
836-
837- if isinstance(obj, JSRegExp):
838- # RegExp methods and properties
839- if key_str in ("test", "exec"):
840- return self._make_regexp_method(obj, key_str)
841- # RegExp properties
842- if key_str in ("source", "flags", "global", "ignoreCase", "multiline",
843- "dotAll", "unicode", "sticky", "lastIndex"):
844- return obj.get(key_str)
845- return UNDEFINED
846-
847- if isinstance(obj, JSFunction):
848- # Function methods
849- if key_str in ("bind", "call", "apply", "toString"):
850- return self._make_function_method(obj, key_str)
851- if key_str == "length":
852- return len(obj.params)
853- if key_str == "name":
854- return obj.name
855- return UNDEFINED
856-
857- if isinstance(obj, JSObject):
858- # Built-in Object methods
859- if key_str in ("toString", "hasOwnProperty"):{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 50,
"offset": 855
} 855→ return UNDEFINED
856→
857→ if isinstance(obj, JSObject):
858→ # Built-in Object methods
859→ if key_str in ("toString", "hasOwnProperty"):
860→ return self._make_object_method(obj, key_str)
861→ # Check for getter
862→ getter = obj.get_getter(key_str)
863→ if getter is not None:
864→ return self._invoke_getter(getter, obj)
865→ return obj.get(key_str)
866→
867→ if isinstance(obj, str):
868→ # String character access
869→ try:
870→ idx = int(key_str)
871→ if 0 <= idx < len(obj):
872→ return obj[idx]
873→ except ValueError:
874→ pass
875→ if key_str == "length":
876→ return len(obj)
877→ # String methods
878→ string_methods = [
879→ "charAt", "charCodeAt", "indexOf", "lastIndexOf",
880→ "substring", "slice", "split", "toLowerCase", "toUpperCase",
881→ "trim", "concat", "repeat", "startsWith", "endsWith",
882→ "includes", "replace", "match", "search", "toString",
883→ ]
884→ if key_str in string_methods:
885→ return self._make_string_method(obj, key_str)
886→ return UNDEFINED
887→
888→ if isinstance(obj, (int, float)):
889→ # Number methods
890→ if key_str in ("toFixed", "toString"):
891→ return self._make_number_method(obj, key_str)
892→ return UNDEFINED
893→
894→ return UNDEFINED
895→
896→ def _make_array_method(self, arr: JSArray, method: str) -> Any:
897→ """Create a bound array method."""
898→ vm = self # Reference for closures
899→
900→ def push_fn(*args):
901→ for arg in args:
902→ arr.push(arg)
903→ return arr.length
904→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
{
"-A": 20,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "def _invoke_getter"
}1519: def _invoke_getter(self, getter: Any, this_val: JSValue) -> JSValue: 1520- """Invoke a getter function and return its result.""" 1521- if isinstance(getter, JSFunction): 1522- # Save current state 1523- old_stack_len = len(self.stack) 1524- # Invoke the getter with no arguments 1525- self._invoke_js_function(getter, [], this_val) 1526- # The result is on the stack 1527- if len(self.stack) > old_stack_len: 1528- return self.stack.pop() 1529- return UNDEFINED 1530- elif callable(getter): 1531- return getter() 1532- return UNDEFINED 1533- 1534- def _invoke_setter(self, setter: Any, this_val: JSValue, value: JSValue) -> None: 1535- """Invoke a setter function.""" 1536- if isinstance(setter, JSFunction): 1537- # Invoke the setter with the value as argument 1538- self._invoke_js_function(setter, [value], this_val) 1539- # Setter returns nothing, discard any result
Ah, I see the issue! _invoke_getter calls _invoke_js_function and expects the result on the stack. But when there's a nested call, it might be affecting the call stack or instruction pointer. Let me check how _invoke_js_function works.
Actually the issue might be that the CALL opcode after GET_PROP tries to call the function, but since we did a nested call, something might be corrupted.
Let me debug more specifically:
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
ctx.eval('''
var a = {get x() { return 42; }};
function test(val) { console.log(\"test called with: \" + val); return val; }
''')
# First try without getter in argument
print('Test 1: test(42)...')
result = ctx.eval('test(42)')
print(f'Result: {result}')
# Now with getter in argument
print('Test 2: test(a.x)...')
result = ctx.eval('test(a.x)')
print(f'Result: {result}')
" 2>&1Exit code 1
Test 1: test(42)...
test called with: 42
Result: 42
Test 2: test(a.x)...
Traceback (most recent call last):
File "<string>", line 18, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 553, in _execute_opcode
self._call_function(arg, None)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1559, in _call_function
raise JSTypeError(f"{callee} is not a function")
mquickjs_python.errors.JSTypeError: TypeError: undefined is not a functionThe problem is that when we call a getter synchronously (not as a bytecode operation), the call stack is being modified. The issue is in _invoke_getter calling _invoke_js_function.
Let me trace through what happens:
1. test(a.x) is being compiled to: LOAD_NAME test, LOAD_NAME a, LOAD_CONST "x", GET_PROP, CALL 1
2. Stack before GET_PROP: [test, a]
3. GET_PROP pops key and obj, calls _get_property which calls _invoke_getter
4. _invoke_getter calls _invoke_js_function which pushes a new frame on the call stack
5. The issue is that the getter function is being executed and we're returning UNDEFINED
Wait - let me check _invoke_js_function:
{
"-A": 50,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "def _invoke_js_function"
}1627: def _invoke_js_function(
1628- self,
1629- func: JSFunction,
1630- args: List[JSValue],
1631- this_val: JSValue,
1632- is_constructor: bool = False,
1633- new_target: JSValue = None,
1634- ) -> None:
1635- """Invoke a JavaScript function."""
1636- # Handle bound functions
1637- if hasattr(func, '_bound_this'):
1638- this_val = func._bound_this
1639- if hasattr(func, '_bound_args'):
1640- args = list(func._bound_args) + list(args)
1641- if hasattr(func, '_original_func'):
1642- func = func._original_func
1643-
1644- compiled = getattr(func, '_compiled', None)
1645- if compiled is None:
1646- raise JSTypeError("Function has no bytecode")
1647-
1648- # Prepare locals (parameters + arguments + local variables)
1649- locals_list = [UNDEFINED] * compiled.num_locals
1650- for i, arg in enumerate(args):
1651- if i < len(compiled.params):
1652- locals_list[i] = arg
1653-
1654- # Create 'arguments' object (stored after params in locals)
1655- # The 'arguments' slot is at index len(compiled.params)
1656- arguments_slot = len(compiled.params)
1657- if arguments_slot < compiled.num_locals:
1658- arguments_obj = JSArray()
1659- arguments_obj._elements = list(args)
1660- locals_list[arguments_slot] = arguments_obj
1661-
1662- # For named function expressions, bind the function name to itself
1663- # This allows recursive calls like: var f = function fact(n) { return fact(n-1); }
1664- if compiled.name and compiled.name in compiled.locals:
1665- name_slot = compiled.locals.index(compiled.name)
1666- if name_slot >= len(compiled.params) + 1: # After params and arguments
1667- locals_list[name_slot] = func
1668-
1669- # Get closure cells from the function
1670- closure_cells = getattr(func, '_closure_cells', None)
1671-
1672- # Create cell storage for variables that will be captured by inner functions
1673- cell_storage = None
1674- if compiled.cell_vars:
1675- cell_storage = []
1676- for var_name in compiled.cell_vars:
1677- # Find the initial value from localsI see - _invoke_js_function pushes a new frame and returns (doesn't wait for execution). This means the getter function is queued but not executed yet. The issue is that _invoke_getter expects immediate execution but _invoke_js_function just schedules the function call.Looking at _invoke_getter:
python
def _invoke_getter(self, getter: Any, this_val: JSValue) -> JSValue:
"""Invoke a getter function and return its result."""
if isinstance(getter, JSFunction):
# Save current state
old_stack_len = len(self.stack)
# Invoke the getter with no arguments
self._invoke_js_function(getter, [], this_val)
# The result is on the stack
if len(self.stack) > old_stack_len:
return self.stack.pop()
return UNDEFINEDThis is buggy because _invoke_js_function just creates a new frame and adds it to the call stack - it doesn't actually execute anything. The execution happens in _execute which is the main loop. So _invoke_getter needs to actually run the getter synchronously by executing until it returns.There's actually a different approach used elsewhere - let me check how _call_function does it, or find an example of synchronous execution:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 120,
"offset": 1519
} 1519→ def _invoke_getter(self, getter: Any, this_val: JSValue) -> JSValue:
1520→ """Invoke a getter function and return its result."""
1521→ if isinstance(getter, JSFunction):
1522→ # Save current state
1523→ old_stack_len = len(self.stack)
1524→ # Invoke the getter with no arguments
1525→ self._invoke_js_function(getter, [], this_val)
1526→ # The result is on the stack
1527→ if len(self.stack) > old_stack_len:
1528→ return self.stack.pop()
1529→ return UNDEFINED
1530→ elif callable(getter):
1531→ return getter()
1532→ return UNDEFINED
1533→
1534→ def _invoke_setter(self, setter: Any, this_val: JSValue, value: JSValue) -> None:
1535→ """Invoke a setter function."""
1536→ if isinstance(setter, JSFunction):
1537→ # Invoke the setter with the value as argument
1538→ self._invoke_js_function(setter, [value], this_val)
1539→ # Setter returns nothing, discard any result
1540→ if self.stack:
1541→ self.stack.pop()
1542→ elif callable(setter):
1543→ setter(value)
1544→
1545→ def _call_function(self, arg_count: int, this_val: Optional[JSValue]) -> None:
1546→ """Call a function."""
1547→ args = []
1548→ for _ in range(arg_count):
1549→ args.insert(0, self.stack.pop())
1550→ callee = self.stack.pop()
1551→
1552→ if isinstance(callee, JSFunction):
1553→ self._invoke_js_function(callee, args, this_val or UNDEFINED)
1554→ elif callable(callee):
1555→ # Native function
1556→ result = callee(*args)
1557→ self.stack.append(result if result is not None else UNDEFINED)
1558→ else:
1559→ raise JSTypeError(f"{callee} is not a function")
1560→
1561→ def _call_method(self, method: JSValue, this_val: JSValue, args: List[JSValue]) -> None:
1562→ """Call a method."""
1563→ if isinstance(method, JSFunction):
1564→ self._invoke_js_function(method, args, this_val)
1565→ elif callable(method):
1566→ result = method(*args)
1567→ self.stack.append(result if result is not None else UNDEFINED)
1568→ else:
1569→ raise JSTypeError(f"{method} is not a function")
1570→
1571→ def _call_callback(self, callback: JSValue, args: List[JSValue]) -> JSValue:
1572→ """Call a callback function synchronously and return the result."""
1573→ if isinstance(callback, JSFunction):
1574→ # Save current stack position
1575→ stack_len = len(self.stack)
1576→
1577→ # Invoke the function
1578→ self._invoke_js_function(callback, args, UNDEFINED)
1579→
1580→ # Execute until the call returns
1581→ while len(self.call_stack) > 1:
1582→ self._check_limits()
1583→ frame = self.call_stack[-1]
1584→ func = frame.func
1585→ bytecode = func.bytecode
1586→
1587→ if frame.ip >= len(bytecode):
1588→ self.call_stack.pop()
1589→ if len(self.stack) > stack_len:
1590→ return self.stack.pop()
1591→ return UNDEFINED
1592→
1593→ op = OpCode(bytecode[frame.ip])
1594→ frame.ip += 1
1595→
1596→ # Get argument if needed
1597→ arg = None
1598→ if op in (OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE, OpCode.TRY_START):
1599→ low = bytecode[frame.ip]
1600→ high = bytecode[frame.ip + 1]
1601→ arg = low | (high << 8)
1602→ frame.ip += 2
1603→ elif op in (
1604→ OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME,
1605→ OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL,
1606→ OpCode.LOAD_CLOSURE, OpCode.STORE_CLOSURE,
1607→ OpCode.LOAD_CELL, OpCode.STORE_CELL,
1608→ OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
1609→ OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
1610→ OpCode.MAKE_CLOSURE,
1611→ ):
1612→ arg = bytecode[frame.ip]
1613→ frame.ip += 1
1614→
1615→ self._execute_opcode(op, arg, frame)
1616→
1617→ # Get result from stack
1618→ if len(self.stack) > stack_len:
1619→ return self.stack.pop()
1620→ return UNDEFINED
1621→ elif callable(callback):
1622→ result = callback(*args)
1623→ return result if result is not None else UNDEFINED
1624→ else:
1625→ raise JSTypeError(f"{callback} is not a function")
1626→
1627→ def _invoke_js_function(
1628→ self,
1629→ func: JSFunction,
1630→ args: List[JSValue],
1631→ this_val: JSValue,
1632→ is_constructor: bool = False,
1633→ new_target: JSValue = None,
1634→ ) -> None:
1635→ """Invoke a JavaScript function."""
1636→ # Handle bound functions
1637→ if hasattr(func, '_bound_this'):
1638→ this_val = func._bound_this
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see there's a _call_callback function that runs synchronously by executing until the call returns. The _invoke_getter and _invoke_setter should use this synchronous execution pattern.Let me fix _invoke_getter and _invoke_setter:
I see the issue. _invoke_getter and _invoke_setter need to use synchronous execution like _call_callback. Let me fix them:
def _invoke_getter(self, getter: Any, this_val: JSValue) -> JSValue:
"""Invoke a getter function and return its result."""
if isinstance(getter, JSFunction):
# Save current state
old_stack_len = len(self.stack)
# Invoke the getter with no arguments
self._invoke_js_function(getter, [], this_val)
# The result is on the stack
if len(self.stack) > old_stack_len:
return self.stack.pop()
return UNDEFINED
elif callable(getter):
return getter()
return UNDEFINED
def _invoke_setter(self, setter: Any, this_val: JSValue, value: JSValue) -> None:
"""Invoke a setter function."""
if isinstance(setter, JSFunction):
# Invoke the setter with the value as argument
self._invoke_js_function(setter, [value], this_val)
# Setter returns nothing, discard any result
if self.stack:
self.stack.pop()
elif callable(setter):
setter(value) def _invoke_getter(self, getter: Any, this_val: JSValue) -> JSValue:
"""Invoke a getter function and return its result."""
if isinstance(getter, JSFunction):
# Use synchronous execution (like _call_callback)
return self._call_callback(getter, [], this_val)
elif callable(getter):
return getter()
return UNDEFINED
def _invoke_setter(self, setter: Any, this_val: JSValue, value: JSValue) -> None:
"""Invoke a setter function."""
if isinstance(setter, JSFunction):
# Use synchronous execution (like _call_callback)
self._call_callback(setter, [value], this_val)
elif callable(setter):
setter(value)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 1515→ key_str = to_string(key) if not isinstance(key, str) else key 1516→ return obj.delete(key_str) 1517→ return False 1518→ 1519→ def _invoke_getter(self, getter: Any, this_val: JSValue) -> JSValue: 1520→ """Invoke a getter function and return its result.""" 1521→ if isinstance(getter, JSFunction): 1522→ # Use synchronous execution (like _call_callback) 1523→ return self._call_callback(getter, [], this_val) 1524→ elif callable(getter): 1525→ return getter() 1526→ return UNDEFINED 1527→ 1528→ def _invoke_setter(self, setter: Any, this_val: JSValue, value: JSValue) -> None: 1529→ """Invoke a setter function.""" 1530→ if isinstance(setter, JSFunction): 1531→ # Use synchronous execution (like _call_callback) 1532→ self._call_callback(setter, [value], this_val) 1533→ elif callable(setter): 1534→ setter(value) 1535→ 1536→ def _call_function(self, arg_count: int, this_val: Optional[JSValue]) -> None: 1537→ """Call a function.""" 1538→ args = []
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 10,
"offset": 1558
} 1558→ self.stack.append(result if result is not None else UNDEFINED)
1559→ else:
1560→ raise JSTypeError(f"{method} is not a function")
1561→
1562→ def _call_callback(self, callback: JSValue, args: List[JSValue]) -> JSValue:
1563→ """Call a callback function synchronously and return the result."""
1564→ if isinstance(callback, JSFunction):
1565→ # Save current stack position
1566→ stack_len = len(self.stack)
1567→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
def _call_callback(self, callback: JSValue, args: List[JSValue]) -> JSValue:
"""Call a callback function synchronously and return the result."""
if isinstance(callback, JSFunction):
# Save current stack position
stack_len = len(self.stack)
# Invoke the function
self._invoke_js_function(callback, args, UNDEFINED) def _call_callback(self, callback: JSValue, args: List[JSValue], this_val: JSValue = None) -> JSValue:
"""Call a callback function synchronously and return the result."""
if isinstance(callback, JSFunction):
# Save current stack position
stack_len = len(self.stack)
# Invoke the function
self._invoke_js_function(callback, args, this_val if this_val is not None else UNDEFINED)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
1558→ self.stack.append(result if result is not None else UNDEFINED)
1559→ else:
1560→ raise JSTypeError(f"{method} is not a function")
1561→
1562→ def _call_callback(self, callback: JSValue, args: List[JSValue], this_val: JSValue = None) -> JSValue:
1563→ """Call a callback function synchronously and return the result."""
1564→ if isinstance(callback, JSFunction):
1565→ # Save current stack position
1566→ stack_len = len(self.stack)
1567→
1568→ # Invoke the function
1569→ self._invoke_js_function(callback, args, this_val if this_val is not None else UNDEFINED)
1570→
1571→ # Execute until the call returns
1572→ while len(self.call_stack) > 1:
1573→ self._check_limits()uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
ctx.eval('''
var a = {get x() { return 42; }};
function test(val) { console.log(\"test called with: \" + val); return val; }
''')
# Now with getter in argument
print('Test: test(a.x)...')
result = ctx.eval('test(a.x)')
print(f'Result: {result}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
source = open('tests/test_language.js').read()
ctx = JSContext(time_limit=5.0)
try:
ctx.eval(source)
print('PASSED')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
import traceback
source = open('tests/test_language.js').read()
# Add some tracing
source = source.replace('test_op1();', 'console.log(\"Running test_op1\"); test_op1(); console.log(\"Done test_op1\");')
source = source.replace('test_cvt();', 'console.log(\"Running test_cvt\"); test_cvt(); console.log(\"Done test_cvt\");')
source = source.replace('test_eq();', 'console.log(\"Running test_eq\"); test_eq(); console.log(\"Done test_eq\");')
source = source.replace('test_inc_dec();', 'console.log(\"Running test_inc_dec\"); test_inc_dec(); console.log(\"Done test_inc_dec\");')
source = source.replace('test_op2();', 'console.log(\"Running test_op2\"); test_op2(); console.log(\"Done test_op2\");')
source = source.replace('test_prototype();', 'console.log(\"Running test_prototype\"); test_prototype(); console.log(\"Done test_prototype\");')
source = source.replace('test_arguments();', 'console.log(\"Running test_arguments\"); test_arguments(); console.log(\"Done test_arguments\");')
source = source.replace('test_to_primitive();', 'console.log(\"Running test_to_primitive\"); test_to_primitive(); console.log(\"Done test_to_primitive\");')
source = source.replace('test_labels();', 'console.log(\"Running test_labels\"); test_labels(); console.log(\"Done test_labels\");')
source = source.replace('test_labels2();', 'console.log(\"Running test_labels2\"); test_labels2(); console.log(\"Done test_labels2\");')
ctx = JSContext(time_limit=5.0)
try:
ctx.eval(source)
print('ALL PASSED')
except Exception as e:
traceback.print_exc()
" 2>&1Running test_op1
Done test_op1
Running test_cvt
Done test_cvt
Running test_eq
Done test_eq
Running test_inc_dec
Done test_inc_dec
Running test_op2
Done test_op2
Running test_prototype
Traceback (most recent call last):
File "<string>", line 21, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 274, in _execute_opcode
self.stack.append(self._get_property(obj, key))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 812, in _get_property
raise JSTypeError(f"Cannot read property of {obj}")
mquickjs_python.errors.JSTypeError: TypeError: Cannot read property of undefineduv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test test_prototype
result = ctx.eval('''
function f() { }
f.prototype
''')
print(f'f.prototype: {result}')
result2 = ctx.eval('''
function f() { }
f.prototype.constructor
''')
print(f'f.prototype.constructor: {result2}')
" 2>&1Exit code 1
f.prototype: None
Traceback (most recent call last):
File "<string>", line 13, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 274, in _execute_opcode
self.stack.append(self._get_property(obj, key))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 812, in _get_property
raise JSTypeError(f"Cannot read property of {obj}")
mquickjs_python.errors.JSTypeError: TypeError: Cannot read property of undefinedThe issue is that f.prototype returns None (should return an object). In JavaScript, every function has a prototype property that's an object with a constructor property pointing back to the function.When we create a function, we need to set up its prototype property. Let me check how MAKE_CLOSURE handles this:
The issue is that f.prototype returns None. Every function should have a prototype property. Let me check MAKE_CLOSURE:
{
"-B": 2,
"-C": 30,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "MAKE_CLOSURE"
}129- """Main execution loop."""
130- while self.call_stack:
131- self._check_limits()
132-
133- frame = self.call_stack[-1]
134- func = frame.func
135- bytecode = func.bytecode
136-
137- if frame.ip >= len(bytecode):
138- # End of function
139- return self.stack.pop() if self.stack else UNDEFINED
140-
141- op = OpCode(bytecode[frame.ip])
142- frame.ip += 1
143-
144- # Get argument if needed
145- arg = None
146- if op in (OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE, OpCode.TRY_START):
147- # 16-bit little-endian argument for jumps
148- low = bytecode[frame.ip]
149- high = bytecode[frame.ip + 1]
150- arg = low | (high << 8)
151- frame.ip += 2
152- elif op in (
153- OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME,
154- OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL,
155- OpCode.LOAD_CLOSURE, OpCode.STORE_CLOSURE,
156- OpCode.LOAD_CELL, OpCode.STORE_CELL,
157- OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
158- OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
159: OpCode.MAKE_CLOSURE, OpCode.TYPEOF_NAME,
160- ):
161- arg = bytecode[frame.ip]
162- frame.ip += 1
163-
164- # Execute opcode
165- self._execute_opcode(op, arg, frame)
166-
167- # Check if frame was popped (return)
168- if not self.call_stack:
169- break
170-
171- return self.stack.pop() if self.stack else UNDEFINED
172-
173- def _execute_opcode(self, op: OpCode, arg: Optional[int], frame: CallFrame) -> None:
174- """Execute a single opcode."""
175-
176- # Stack operations
177- if op == OpCode.POP:
178- if self.stack:
179- self.stack.pop()
180-
181- elif op == OpCode.DUP:
182- self.stack.append(self.stack[-1])
183-
184- elif op == OpCode.DUP2:
185- # Duplicate top two items: a, b -> a, b, a, b
186- self.stack.append(self.stack[-2])
187- self.stack.append(self.stack[-2])
188-
189- elif op == OpCode.SWAP:
--
641- # Strings iterate over characters
642- values = list(iterable)
643- elif isinstance(iterable, list):
644- values = list(iterable)
645- else:
646- values = []
647- self.stack.append(ForOfIterator(values))
648-
649- elif op == OpCode.FOR_OF_NEXT:
650- iterator = self.stack[-1]
651- if isinstance(iterator, ForOfIterator):
652- value, done = iterator.next()
653- if done:
654- self.stack.append(True)
655- else:
656- self.stack.append(value)
657- self.stack.append(False)
658- else:
659- self.stack.append(True)
660-
661- # Increment/Decrement
662- elif op == OpCode.INC:
663- a = self.stack.pop()
664- self.stack.append(to_number(a) + 1)
665-
666- elif op == OpCode.DEC:
667- a = self.stack.pop()
668- self.stack.append(to_number(a) - 1)
669-
670- # Closures
671: elif op == OpCode.MAKE_CLOSURE:
672- compiled_func = self.stack.pop()
673- if isinstance(compiled_func, CompiledFunction):
674- js_func = JSFunction(
675- name=compiled_func.name,
676- params=compiled_func.params,
677- bytecode=compiled_func.bytecode,
678- )
679- js_func._compiled = compiled_func
680-
681- # Create prototype object for the function
682- # In JavaScript, every function has a prototype property
683- prototype = JSObject()
684- prototype.set("constructor", js_func)
685- js_func._prototype = prototype
686-
687- # Capture closure cells for free variables
688- if compiled_func.free_vars:
689- closure_cells = []
690- for var_name in compiled_func.free_vars:
691- # First check if it's in our cell_storage (cell var)
692- if frame.cell_storage and var_name in getattr(frame.func, 'cell_vars', []):
693- idx = frame.func.cell_vars.index(var_name)
694- # Share the same cell!
695- closure_cells.append(frame.cell_storage[idx])
696- elif frame.closure_cells and var_name in getattr(frame.func, 'free_vars', []):
697- # Variable is in our own closure
698- idx = frame.func.free_vars.index(var_name)
699- closure_cells.append(frame.closure_cells[idx])
700- elif var_name in frame.func.locals:
701- # Regular local - shouldn't happen if cell_vars is working
--
1571- # Execute until the call returns
1572- while len(self.call_stack) > 1:
1573- self._check_limits()
1574- frame = self.call_stack[-1]
1575- func = frame.func
1576- bytecode = func.bytecode
1577-
1578- if frame.ip >= len(bytecode):
1579- self.call_stack.pop()
1580- if len(self.stack) > stack_len:
1581- return self.stack.pop()
1582- return UNDEFINED
1583-
1584- op = OpCode(bytecode[frame.ip])
1585- frame.ip += 1
1586-
1587- # Get argument if needed
1588- arg = None
1589- if op in (OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE, OpCode.TRY_START):
1590- low = bytecode[frame.ip]
1591- high = bytecode[frame.ip + 1]
1592- arg = low | (high << 8)
1593- frame.ip += 2
1594- elif op in (
1595- OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME,
1596- OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL,
1597- OpCode.LOAD_CLOSURE, OpCode.STORE_CLOSURE,
1598- OpCode.LOAD_CELL, OpCode.STORE_CELL,
1599- OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
1600- OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
1601: OpCode.MAKE_CLOSURE,
1602- ):
1603- arg = bytecode[frame.ip]
1604- frame.ip += 1
1605-
1606- self._execute_opcode(op, arg, frame)
1607-
1608- # Get result from stack
1609- if len(self.stack) > stack_len:
1610- return self.stack.pop()
1611- return UNDEFINED
1612- elif callable(callback):
1613- result = callback(*args)
1614- return result if result is not None else UNDEFINED
1615- else:
1616- raise JSTypeError(f"{callback} is not a function")
1617-
1618- def _invoke_js_function(
1619- self,
1620- func: JSFunction,
1621- args: List[JSValue],
1622- this_val: JSValue,
1623- is_constructor: bool = False,
1624- new_target: JSValue = None,
1625- ) -> None:
1626- """Invoke a JavaScript function."""
1627- # Handle bound functions
1628- if hasattr(func, '_bound_this'):
1629- this_val = func._bound_this
1630- if hasattr(func, '_bound_args'):
1631- args = list(func._bound_args) + list(args)I see that in MAKE_CLOSURE, we do create a prototype and set js_func._prototype = prototype. But the issue is that _get_property is returning None for prototype on JSFunction. Let me check how _get_property handles JSFunction:
I see the issue. The _prototype is being set but when we try to access f.prototype, we're checking JSFunction cases, and prototype isn't handled there. Let me check:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 15,
"offset": 847
} 847→ if isinstance(obj, JSFunction):
848→ # Function methods
849→ if key_str in ("bind", "call", "apply", "toString"):
850→ return self._make_function_method(obj, key_str)
851→ if key_str == "length":
852→ return len(obj.params)
853→ if key_str == "name":
854→ return obj.name
855→ return UNDEFINED
856→
857→ if isinstance(obj, JSObject):
858→ # Built-in Object methods
859→ if key_str in ("toString", "hasOwnProperty"):
860→ return self._make_object_method(obj, key_str)
861→ # Check for getter
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see. When the object is a JSFunction, we only check for "bind", "call", "apply", "toString", "length", and "name", and then return UNDEFINED for anything else. We need to add "prototype" handling:
if isinstance(obj, JSFunction):
# Function methods
if key_str in ("bind", "call", "apply", "toString"):
return self._make_function_method(obj, key_str)
if key_str == "length":
return len(obj.params)
if key_str == "name":
return obj.name
return UNDEFINED if isinstance(obj, JSFunction):
# Function methods
if key_str in ("bind", "call", "apply", "toString"):
return self._make_function_method(obj, key_str)
if key_str == "length":
return len(obj.params)
if key_str == "name":
return obj.name
if key_str == "prototype":
return getattr(obj, '_prototype', UNDEFINED) or UNDEFINED
return UNDEFINEDThe file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
843→ "dotAll", "unicode", "sticky", "lastIndex"):
844→ return obj.get(key_str)
845→ return UNDEFINED
846→
847→ if isinstance(obj, JSFunction):
848→ # Function methods
849→ if key_str in ("bind", "call", "apply", "toString"):
850→ return self._make_function_method(obj, key_str)
851→ if key_str == "length":
852→ return len(obj.params)
853→ if key_str == "name":
854→ return obj.name
855→ if key_str == "prototype":
856→ return getattr(obj, '_prototype', UNDEFINED) or UNDEFINED
857→ return UNDEFINED
858→
859→ if isinstance(obj, JSObject):
860→ # Built-in Object methods
861→ if key_str in ("toString", "hasOwnProperty"):uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test test_prototype
result = ctx.eval('''
function f() { }
f.prototype
''')
print(f'f.prototype: {result}')
result2 = ctx.eval('f.prototype.constructor')
print(f'f.prototype.constructor: {result2}')
# Test the assert
result3 = ctx.eval('f.prototype.constructor === f')
print(f'f.prototype.constructor === f: {result3}')
" 2>&1f.prototype: {'constructor': [Function: f]}
f.prototype.constructor: [Function: f]
f.prototype.constructor === f: Trueuv run python -c "
from mquickjs_python import JSContext
source = open('tests/test_language.js').read()
ctx = JSContext(time_limit=5.0)
try:
ctx.eval(source)
print('PASSED')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1FAILED: JSError: Error: assertion failed: got string:|[object Object]|, expected string:|1234|
There's still an error. This is about toString and valueOf for object to primitive conversion. Let me look at what test is failing:
uv run python -c "
from mquickjs_python import JSContext
import traceback
source = open('tests/test_language.js').read()
# Add some tracing
source = source.replace('test_op1();', 'console.log(\"Running test_op1\"); test_op1(); console.log(\"Done test_op1\");')
source = source.replace('test_cvt();', 'console.log(\"Running test_cvt\"); test_cvt(); console.log(\"Done test_cvt\");')
source = source.replace('test_eq();', 'console.log(\"Running test_eq\"); test_eq(); console.log(\"Done test_eq\");')
source = source.replace('test_inc_dec();', 'console.log(\"Running test_inc_dec\"); test_inc_dec(); console.log(\"Done test_inc_dec\");')
source = source.replace('test_op2();', 'console.log(\"Running test_op2\"); test_op2(); console.log(\"Done test_op2\");')
source = source.replace('test_prototype();', 'console.log(\"Running test_prototype\"); test_prototype(); console.log(\"Done test_prototype\");')
source = source.replace('test_arguments();', 'console.log(\"Running test_arguments\"); test_arguments(); console.log(\"Done test_arguments\");')
source = source.replace('test_to_primitive();', 'console.log(\"Running test_to_primitive\"); test_to_primitive(); console.log(\"Done test_to_primitive\");')
source = source.replace('test_labels();', 'console.log(\"Running test_labels\"); test_labels(); console.log(\"Done test_labels\");')
source = source.replace('test_labels2();', 'console.log(\"Running test_labels2\"); test_labels2(); console.log(\"Done test_labels2\");')
ctx = JSContext(time_limit=5.0)
try:
ctx.eval(source)
print('ALL PASSED')
except Exception as e:
traceback.print_exc()
" 2>&1Running test_op1
Done test_op1
Running test_cvt
Done test_cvt
Running test_eq
Done test_eq
Running test_inc_dec
Done test_inc_dec
Running test_op2
Done test_op2
Running test_prototype
Done test_prototype
Running test_arguments
Done test_arguments
Running test_to_primitive
Traceback (most recent call last):
File "<string>", line 21, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1736, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got string:|[object Object]|, expected string:|1234|The error is in test_to_primitive(). Looking at the test file, test_to_primitive tests:javascript
function test_to_primitive()
{
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
assert(obj + "", "1234"); // This is failing assert(obj * 1, 1234);
}The expected behavior is that when obj + "" is evaluated, it should call valueOf (or toString depending on hint) and the result should be "1234".Currently, it seems like our VM is using [object Object] instead of the custom valueOf/toString methods.The issue is that when converting an object to a primitive (for string concatenation or multiplication), we need to check if the object has custom valueOf or toString methods and call them.Let me look at how ADD handles objects:
The error is in test_to_primitive(). When converting an object to a primitive, we need to check for custom valueOf and toString methods. Let me look at how this is handled in the VM:
{
"-A": 30,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/values.py",
"pattern": "def to_string"
}147:def to_string(value: JSValue) -> str:
148- """Convert a JavaScript value to string."""
149- if value is UNDEFINED:
150- return "undefined"
151- if value is NULL:
152- return "null"
153- if isinstance(value, bool):
154- return "true" if value else "false"
155- if isinstance(value, int):
156- return str(value)
157- if isinstance(value, float):
158- if is_nan(value):
159- return "NaN"
160- if value == float("inf"):
161- return "Infinity"
162- if value == float("-inf"):
163- return "-Infinity"
164- # Handle -0
165- if value == 0 and math.copysign(1, value) < 0:
166- return "0"
167- # Format float nicely
168- s = repr(value)
169- if s.endswith(".0"):
170- return s[:-2]
171- return s
172- if isinstance(value, str):
173- return value
174- # TODO: Handle objects with toString
175- return "[object Object]"
176-
177-I see - the to_string function in values.py has a TODO to handle objects with toString. The issue is that to_string and to_number in values.py don't have access to the VM to call the object's methods.One approach is to add a new function to handle ToPrimitive conversion in the VM, and use that for ADD, MUL, etc. when one of the operands is an object.Let me look at how ADD is handled:
{
"-A": 20,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "OpCode.ADD:"
}336: elif op == OpCode.ADD: 337- b = self.stack.pop() 338- a = self.stack.pop() 339- self.stack.append(self._add(a, b)) 340- 341- elif op == OpCode.SUB: 342- b = self.stack.pop() 343- a = self.stack.pop() 344- self.stack.append(to_number(a) - to_number(b)) 345- 346- elif op == OpCode.MUL: 347- b = self.stack.pop() 348- a = self.stack.pop() 349- a_num = float(to_number(a)) # Use float for proper -0 handling 350- b_num = float(to_number(b)) 351- self.stack.append(a_num * b_num) 352- 353- elif op == OpCode.DIV: 354- b = self.stack.pop() 355- a = self.stack.pop() 356- b_num = to_number(b)
{
"-A": 20,
"output_mode": "content",
"path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"pattern": "def _add"
}725: def _add(self, a: JSValue, b: JSValue) -> JSValue: 726- """JavaScript + operator.""" 727- # String concatenation if either is string 728- if isinstance(a, str) or isinstance(b, str): 729- return to_string(a) + to_string(b) 730- # Numeric addition 731- return to_number(a) + to_number(b) 732- 733- def _to_int32(self, value: JSValue) -> int: 734- """Convert to 32-bit signed integer.""" 735- n = to_number(value) 736- if math.isnan(n) or math.isinf(n) or n == 0: 737- return 0 738- n = int(n) 739- n = n & 0xFFFFFFFF 740- if n >= 0x80000000: 741- n -= 0x100000000 742- return n 743- 744- def _to_uint32(self, value: JSValue) -> int: 745- """Convert to 32-bit unsigned integer."""
I need to add ToPrimitive conversion for objects. When an object is used in + or other operations, JavaScript first tries to convert it to a primitive using either valueOf or toString.For the + operator with hint "default" (string concatenation preference):
1. If value has a Symbol.toPrimitive method, call it (we can skip this for now)
2. Try valueOf() first3. If that returns an object, try toString()
4. If that returns an object too, throw TypeErrorFor numeric operations (*, /, etc.) with hint "number":
1. Try valueOf() first2. Then toString()Let me add a _to_primitive method to the VM that handles this:
I need to add ToPrimitive conversion for objects. Let me add a _to_primitive method to the VM:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 30,
"offset": 720
} 720→ name = frame.func.constants[index]
721→ if isinstance(name, str):
722→ return name
723→ return f"<name_{index}>"
724→
725→ def _add(self, a: JSValue, b: JSValue) -> JSValue:
726→ """JavaScript + operator."""
727→ # String concatenation if either is string
728→ if isinstance(a, str) or isinstance(b, str):
729→ return to_string(a) + to_string(b)
730→ # Numeric addition
731→ return to_number(a) + to_number(b)
732→
733→ def _to_int32(self, value: JSValue) -> int:
734→ """Convert to 32-bit signed integer."""
735→ n = to_number(value)
736→ if math.isnan(n) or math.isinf(n) or n == 0:
737→ return 0
738→ n = int(n)
739→ n = n & 0xFFFFFFFF
740→ if n >= 0x80000000:
741→ n -= 0x100000000
742→ return n
743→
744→ def _to_uint32(self, value: JSValue) -> int:
745→ """Convert to 32-bit unsigned integer."""
746→ n = to_number(value)
747→ if math.isnan(n) or math.isinf(n) or n == 0:
748→ return 0
749→ n = int(n)
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
def _add(self, a: JSValue, b: JSValue) -> JSValue:
"""JavaScript + operator."""
# String concatenation if either is string
if isinstance(a, str) or isinstance(b, str):
return to_string(a) + to_string(b)
# Numeric addition
return to_number(a) + to_number(b) def _to_primitive(self, value: JSValue, hint: str = "default") -> JSValue:
"""Convert an object to a primitive value (ToPrimitive).
hint can be "default", "number", or "string"
"""
if not isinstance(value, JSObject):
return value
# For default hint, try valueOf first (like number), then toString
if hint == "string":
method_order = ["toString", "valueOf"]
else: # default or number
method_order = ["valueOf", "toString"]
for method_name in method_order:
method = value.get(method_name)
if method is UNDEFINED or method is NULL:
continue
if isinstance(method, JSFunction):
result = self._call_callback(method, [], value)
if not isinstance(result, JSObject):
return result
elif callable(method):
result = method()
if not isinstance(result, JSObject):
return result
# If we get here, conversion failed
raise JSTypeError("Cannot convert object to primitive value")
def _add(self, a: JSValue, b: JSValue) -> JSValue:
"""JavaScript + operator."""
# First convert objects to primitives
if isinstance(a, JSObject):
a = self._to_primitive(a, "default")
if isinstance(b, JSObject):
b = self._to_primitive(b, "default")
# String concatenation if either is string
if isinstance(a, str) or isinstance(b, str):
return to_string(a) + to_string(b)
# Numeric addition
return to_number(a) + to_number(b)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
721→ if isinstance(name, str):
722→ return name
723→ return f"<name_{index}>"
724→
725→ def _to_primitive(self, value: JSValue, hint: str = "default") -> JSValue:
726→ """Convert an object to a primitive value (ToPrimitive).
727→
728→ hint can be "default", "number", or "string"
729→ """
730→ if not isinstance(value, JSObject):
731→ return value
732→
733→ # For default hint, try valueOf first (like number), then toString
734→ if hint == "string":
735→ method_order = ["toString", "valueOf"]
736→ else: # default or number
737→ method_order = ["valueOf", "toString"]
738→
739→ for method_name in method_order:
740→ method = value.get(method_name)
741→ if method is UNDEFINED or method is NULL:
742→ continue
743→ if isinstance(method, JSFunction):
744→ result = self._call_callback(method, [], value)
745→ if not isinstance(result, JSObject):
746→ return result
747→ elif callable(method):
748→ result = method()
749→ if not isinstance(result, JSObject):
750→ return result
751→
752→ # If we get here, conversion failed
753→ raise JSTypeError("Cannot convert object to primitive value")
754→
755→ def _add(self, a: JSValue, b: JSValue) -> JSValue:
756→ """JavaScript + operator."""
757→ # First convert objects to primitives
758→ if isinstance(a, JSObject):
759→ a = self._to_primitive(a, "default")
760→ if isinstance(b, JSObject):
761→ b = self._to_primitive(b, "default")
762→
763→ # String concatenation if either is string
764→ if isinstance(a, str) or isinstance(b, str):
765→ return to_string(a) + to_string(b)
766→ # Numeric addition
767→ return to_number(a) + to_number(b)
768→
769→ def _to_int32(self, value: JSValue) -> int:
770→ """Convert to 32-bit signed integer."""
771→ n = to_number(value)Now I need to also update MUL, DIV, etc. to use _to_primitive with "number" hint. But actually, to_number should use it too. However, that's complicated because to_number is in values.py without access to the VM.Let me instead add a helper method _to_number in the VM that handles objects first:
def _add(self, a: JSValue, b: JSValue) -> JSValue:
"""JavaScript + operator."""
# First convert objects to primitives
if isinstance(a, JSObject):
a = self._to_primitive(a, "default")
if isinstance(b, JSObject):
b = self._to_primitive(b, "default")
# String concatenation if either is string
if isinstance(a, str) or isinstance(b, str):
return to_string(a) + to_string(b)
# Numeric addition
return to_number(a) + to_number(b) def _to_number(self, value: JSValue) -> Union[int, float]:
"""Convert to number, with ToPrimitive for objects."""
if isinstance(value, JSObject):
value = self._to_primitive(value, "number")
return to_number(value)
def _add(self, a: JSValue, b: JSValue) -> JSValue:
"""JavaScript + operator."""
# First convert objects to primitives
if isinstance(a, JSObject):
a = self._to_primitive(a, "default")
if isinstance(b, JSObject):
b = self._to_primitive(b, "default")
# String concatenation if either is string
if isinstance(a, str) or isinstance(b, str):
return to_string(a) + to_string(b)
# Numeric addition
return to_number(a) + to_number(b)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
751→
752→ # If we get here, conversion failed
753→ raise JSTypeError("Cannot convert object to primitive value")
754→
755→ def _to_number(self, value: JSValue) -> Union[int, float]:
756→ """Convert to number, with ToPrimitive for objects."""
757→ if isinstance(value, JSObject):
758→ value = self._to_primitive(value, "number")
759→ return to_number(value)
760→
761→ def _add(self, a: JSValue, b: JSValue) -> JSValue:
762→ """JavaScript + operator."""
763→ # First convert objects to primitives
764→ if isinstance(a, JSObject):
765→ a = self._to_primitive(a, "default")
766→ if isinstance(b, JSObject):
767→ b = self._to_primitive(b, "default")
768→
769→ # String concatenation if either is string
770→ if isinstance(a, str) or isinstance(b, str):
771→ return to_string(a) + to_string(b)
772→ # Numeric addition
773→ return to_number(a) + to_number(b)
774→
775→ def _to_int32(self, value: JSValue) -> int:
776→ """Convert to 32-bit signed integer."""
777→ n = to_number(value) elif op == OpCode.MUL:
b = self.stack.pop()
a = self.stack.pop()
a_num = float(to_number(a)) # Use float for proper -0 handling
b_num = float(to_number(b))
self.stack.append(a_num * b_num) elif op == OpCode.MUL:
b = self.stack.pop()
a = self.stack.pop()
a_num = float(self._to_number(a)) # Use float for proper -0 handling
b_num = float(self._to_number(b))
self.stack.append(a_num * b_num)The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file: 342→ b = self.stack.pop() 343→ a = self.stack.pop() 344→ self.stack.append(to_number(a) - to_number(b)) 345→ 346→ elif op == OpCode.MUL: 347→ b = self.stack.pop() 348→ a = self.stack.pop() 349→ a_num = float(self._to_number(a)) # Use float for proper -0 handling 350→ b_num = float(self._to_number(b)) 351→ self.stack.append(a_num * b_num) 352→ 353→ elif op == OpCode.DIV: 354→ b = self.stack.pop() 355→ a = self.stack.pop()
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test test_to_primitive
result = ctx.eval('''
var obj;
obj = { x : \"abc\", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
obj + \"\"
''')
print(f'obj + \"\": {result!r}')
result2 = ctx.eval('obj * 1')
print(f'obj * 1: {result2}')
" 2>&1Exit code 1
Traceback (most recent call last):
File "<string>", line 2, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/__init__.py", line 12, in <module>
from .context import JSContext
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 11, in <module>
from .vm import VM
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 71, in <module>
class VM:
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 755, in VM
def _to_number(self, value: JSValue) -> Union[int, float]:
^^^^^
NameError: name 'Union' is not defined{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 15,
"offset": 1
} 1→"""Virtual machine for executing JavaScript bytecode."""
2→
3→import math
4→import time
5→from typing import Any, Dict, List, Optional, Tuple
6→from dataclasses import dataclass
7→
8→from .opcodes import OpCode
9→from .compiler import CompiledFunction
10→from .values import (
11→ UNDEFINED, NULL, JSUndefined, JSNull, JSValue,
12→ JSObject, JSArray, JSFunction, JSRegExp,
13→ to_boolean, to_number, to_string, js_typeof,
14→)
15→from .errors import (
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
from typing import Any, Dict, List, Optional, Tuple
from typing import Any, Dict, List, Optional, Tuple, Union
The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
1→"""Virtual machine for executing JavaScript bytecode."""
2→
3→import math
4→import time
5→from typing import Any, Dict, List, Optional, Tuple, Union
6→from dataclasses import dataclass
7→
8→from .opcodes import OpCode
9→from .compiler import CompiledFunctionuv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test test_to_primitive
result = ctx.eval('''
var obj;
obj = { x : \"abc\", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
obj + \"\"
''')
print(f'obj + \"\": {result!r}')
result2 = ctx.eval('obj * 1')
print(f'obj * 1: {result2}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
source = open('tests/test_language.js').read()
ctx = JSContext(time_limit=5.0)
try:
ctx.eval(source)
print('PASSED')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1Ah, the test expects a string "1234" but we're returning a number 1234. Let me check the test again:javascriptassert(obj + "", "1234");When we add "" to the object, it should be converted to a string. The issue is that valueOf returns 1234 (a number), and then we're concatenating with "". Let me check how we handle this:1. obj is converted to primitive with "default" hint -> valueOf returns 1234 (number)
2. Now we have 1234 + ""
3. Since "" is a string, we should use to_string on 1234, which returns "1234"
So the result should be "1234" (string). Let me check what's happening:
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
result = ctx.eval('''
var obj;
obj = { x : \"abc\", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
var r = obj + \"\";
typeof r + \":\" + r
''')
print(f'Result: {result}')
" 2>&1Hmm, the result is string:1234 which seems correct. Let me check what the assertion is comparing:
uv run python -c "
from mquickjs_python import JSContext
import traceback
source = open('tests/test_language.js').read()
# Add some tracing
source = source.replace('test_op1();', 'console.log(\"Running test_op1\"); test_op1(); console.log(\"Done test_op1\");')
source = source.replace('test_cvt();', 'console.log(\"Running test_cvt\"); test_cvt(); console.log(\"Done test_cvt\");')
source = source.replace('test_eq();', 'console.log(\"Running test_eq\"); test_eq(); console.log(\"Done test_eq\");')
source = source.replace('test_inc_dec();', 'console.log(\"Running test_inc_dec\"); test_inc_dec(); console.log(\"Done test_inc_dec\");')
source = source.replace('test_op2();', 'console.log(\"Running test_op2\"); test_op2(); console.log(\"Done test_op2\");')
source = source.replace('test_prototype();', 'console.log(\"Running test_prototype\"); test_prototype(); console.log(\"Done test_prototype\");')
source = source.replace('test_arguments();', 'console.log(\"Running test_arguments\"); test_arguments(); console.log(\"Done test_arguments\");')
source = source.replace('test_to_primitive();', 'console.log(\"Running test_to_primitive\"); test_to_primitive(); console.log(\"Done test_to_primitive\");')
source = source.replace('test_labels();', 'console.log(\"Running test_labels\"); test_labels(); console.log(\"Done test_labels\");')
source = source.replace('test_labels2();', 'console.log(\"Running test_labels2\"); test_labels2(); console.log(\"Done test_labels2\");')
ctx = JSContext(time_limit=5.0)
try:
ctx.eval(source)
print('ALL PASSED')
except Exception as e:
traceback.print_exc()
" 2>&1Running test_op1
Done test_op1
Running test_cvt
Done test_cvt
Running test_eq
Done test_eq
Running test_inc_dec
Done test_inc_dec
Running test_op2
Done test_op2
Running test_prototype
Done test_prototype
Running test_arguments
Done test_arguments
Running test_to_primitive
Traceback (most recent call last):
File "<string>", line 21, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got number:|1234|, expected string:|1234|Hmm, the traceback shows that when test_to_primitive calls assert(obj + "", "1234"), the assertion logic is trying to compare actual with expected, and it's calling _add on something from the assert function. The assertion function's get_full_type(o) has typeof(o), and when it checks that, it might be doing an add operation somewhere.Let me look at the full assert function in test_language.js:```javascript
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === 'object') {
if (o === null)
return 'null';
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (actual === expected) {
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === 'number') { if (isNaN(actual) && isNaN(expected))
return true; }
if (typeof actual === 'object') {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor && actual.toString() === expected.toString())
return;
}
}
// Should output the source file and line number and extract
// the expression from the assert call
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " + get_full_type(expected) + ":|" + expected + "|" +
(message ? " (" + message + ")" : ""));
}```
I see a complex interaction happening with type conversion. The error message reveals a type mismatch where a number is being generated instead of a string. The nested execution in _add and _to_primitive suggests something unusual is occurring during type coercion. The problem seems to involve how primitive conversion is being handled during the string concatenation operation.
The valueOf function execution in a new frame might be disrupting the expected type transformation, causing the unexpected numeric result when attempting to convert an object to a string.
When converting objects to primitives, the process seems to be returning a number instead of a string. Tracing the conversion steps reveals that after ToPrimitive, the values become 1234 (number) and an empty string, which should trigger string concatenation but isn't behaving as expected.
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Detailed test
result = ctx.eval('''
var obj = { valueOf: function() { return 1234; } };
var result = obj + \"\";
console.log(\"Type: \" + typeof result);
console.log(\"Value: \" + result);
typeof result === \"string\" && result === \"1234\"
''')
print(f'Test passed: {result}')
" 2>&1The basic test passes. So the issue must be something with the nested function calls in the test_to_primitive test. Let me check if there's an issue when the valueOf function is accessing this:
uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Test with this
result = ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
var result = obj + \"\";
console.log(\"Type: \" + typeof result);
console.log(\"Value: \" + result);
typeof result === \"string\" && result === \"1234\"
''')
print(f'Test passed: {result}')
" 2>&1uv run python -c "
from mquickjs_python import JSContext
ctx = JSContext()
# Exact test from test_language.js
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === \"object\") {
if (o === null)
return \"null\";
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (actual === expected) {
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === \"number\") {
if (isNaN(actual) && isNaN(expected))
return true;
}
if (typeof actual === \"object\") {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor
&& actual.toString() === expected.toString())
return;
}
}
throw_error(\"assertion failed: got \" +
get_full_type(actual) + \":|\" + actual + \"|, expected \" +
get_full_type(expected) + \":|\" + expected + \"|\" +
(message ? \" (\" + message + \")\" : \"\"));
}
function test_to_primitive()
{
var obj;
obj = { x : \"abc\", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
console.log(\"Testing obj + empty string...\");
var result = obj + \"\";
console.log(\"Result: \" + result);
console.log(\"Type: \" + typeof result);
assert(obj + \"\", \"1234\");
console.log(\"First assert passed\");
assert(obj * 1, 1234);
console.log(\"Second assert passed\");
}
test_to_primitive();
''')
print('PASSED')
" 2>&1Exit code 1
Traceback (most recent call last):
File "<string>", line 7, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 642, in eval
ast = parser.parse()
^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 114, in parse
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 163, in _parse_statement
return self._parse_function_declaration()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 391, in _parse_function_declaration
body = self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 133, in _parse_statement
return self._parse_if_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 210, in _parse_if_statement
consequent = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 127, in _parse_statement
return self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 133, in _parse_statement
return self._parse_if_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 210, in _parse_if_statement
consequent = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 127, in _parse_statement
return self._parse_block_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 182, in _parse_block_statement
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 133, in _parse_statement
return self._parse_if_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 208, in _parse_if_statement
test = self._parse_expression()
^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 421, in _parse_expression
expr = self._parse_assignment_expression(exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 435, in _parse_assignment_expression
if self._is_arrow_function_single_param():
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 466, in _is_arrow_function_single_param
self._advance() # identifier
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 54, in _advance
self.current = self.lexer.next_token()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/lexer.py", line 388, in next_token
raise JSSyntaxError(f"Unexpected character: {ch!r}", line, column)
mquickjs_python.errors.JSSyntaxError: SyntaxError: Unexpected character: '\\'uv run python << 'EOF'
from mquickjs_python import JSContext
ctx = JSContext()
# Split into parts
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
''')
ctx.eval('''
function assert(actual, expected, message) {
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (actual === expected) {
return;
}
}
throw_error("assertion failed: actual=" + typeof actual + ":" + actual + ", expected=" + typeof expected + ":" + expected);
}
''')
# Test
result = ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
var result = obj + "";
console.log("Result type: " + typeof result);
console.log("Result value: " + result);
assert(result, "1234");
"OK"
''')
print(f'Result: {result}')
EOF
OK, so it's working in isolation. The issue must be something else in test_language.js. Let me check if there's an issue with the multiple evals from the test file:
uv run python << 'EOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Run up to test_to_primitive
source = open('tests/test_language.js').read()
# Find just the helper and test_to_primitive function
lines = source.split('\n')
# Find test_to_primitive
for i, line in enumerate(lines):
if 'function test_to_primitive' in line:
start = i
break
# Find end of test_to_primitive
depth = 0
for i in range(start, len(lines)):
depth += lines[i].count('{') - lines[i].count('}')
if depth == 0 and i > start:
end = i
break
# Extract just test_to_primitive and its call
test_fn = '\n'.join(lines[start:end+1])
# Run just with the helper
ctx.eval(source[:source.find('test_op1();')])
print("Helper functions loaded")
# Run just test_to_primitive
ctx.eval(test_fn)
print("test_to_primitive function defined")
ctx.eval("test_to_primitive();")
print("test_to_primitive() PASSED")
EOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 35, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got number:|1234|, expected string:|1234|
Helper functions loaded
test_to_primitive function definedThe issue is happening specifically when using the original assert function. The error message "got number:|1234|" says it's getting a number. Let me look at the original test more carefully.The get_full_type function does typeof(o). If o is 1234 (a number), typeof should return "number". But if o is "1234" (a string), typeof should return "string".The issue is that somehow obj + "" is returning a number instead of a string when called from within the assert function. Let me add some debugging:
uv run python << 'EOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Simplified test
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
console.log("get_full_type: o=" + o + ", type=" + type);
return type;
}
if (typeof actual !== typeof expected) {
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " +
get_full_type(expected) + ":|" + expected + "|");
}
if (actual !== expected) {
throw_error("values not equal");
}
}
''')
# Test
ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
console.log("Before add...");
var result = obj + "";
console.log("After add, result = " + result + ", typeof = " + typeof result);
console.log("Calling assert...");
assert(result, "1234");
console.log("Assert passed!");
''')
print("ALL PASSED")
EOF
Before add... After add, result = 1234, typeof = string Calling assert... Assert passed! ALL PASSED
Interesting! It passes when I use result as a variable. Let me try with the inline expression like in the original test:
uv run python << 'EOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Simplified test
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
console.log("get_full_type: o=" + o + ", type=" + type);
return type;
}
if (typeof actual !== typeof expected) {
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " +
get_full_type(expected) + ":|" + expected + "|");
}
if (actual !== expected) {
throw_error("values not equal");
}
}
''')
# Test with inline expression
ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
console.log("Calling assert(obj + \"\", \"1234\")...");
assert(obj + "", "1234");
console.log("Assert passed!");
''')
print("ALL PASSED")
EOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 30, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 642, in eval
ast = parser.parse()
^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 114, in parse
stmt = self._parse_statement()
^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 175, in _parse_statement
return self._parse_expression_statement()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 409, in _parse_expression_statement
expr = self._parse_expression()
^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 421, in _parse_expression
expr = self._parse_assignment_expression(exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 443, in _parse_assignment_expression
expr = self._parse_conditional_expression(exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 548, in _parse_conditional_expression
expr = self._parse_binary_expression(0, exclude_in)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 560, in _parse_binary_expression
left = self._parse_unary_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 662, in _parse_unary_expression
return self._parse_postfix_expression()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 689, in _parse_postfix_expression
self._expect(TokenType.RPAREN, "Expected ')' after arguments")
File "/home/user/mquickjs-python/src/mquickjs_python/parser.py", line 71, in _expect
raise self._error(message)
mquickjs_python.errors.JSSyntaxError: SyntaxError: Expected ')' after argumentsuv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Simplified test
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
console.log("get_full_type: o=" + o + ", type=" + type);
return type;
}
if (typeof actual !== typeof expected) {
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " +
get_full_type(expected) + ":|" + expected + "|");
}
if (actual !== expected) {
throw_error("values not equal");
}
}
''')
# Test with inline expression - using single quotes in JS
ctx.eval("""
var obj = { y: 1234, valueOf: function() { return this.y; } };
console.log('Calling assert(obj + "", "1234")...');
assert(obj + "", "1234");
console.log('Assert passed!');
""")
print("ALL PASSED")
PYEOF
OK, it passes. So the issue is something specific to the exact assert function and test in the original test_language.js. Let me check the original assert more closely:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Use the exact assert from test_language.js
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === 'object') {
if (o === null)
return 'null';
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (actual === expected) {
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === 'number') {
if (isNaN(actual) && isNaN(expected))
return true;
}
if (typeof actual === 'object') {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor
&& actual.toString() === expected.toString())
return;
}
}
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " +
get_full_type(expected) + ":|" + expected + "|" +
(message ? " (" + message + ")" : ""));
}
''')
# Test with inline expression
ctx.eval("""
var obj = { y: 1234, valueOf: function() { return this.y; } };
console.log('Testing assert(obj + "", "1234")...');
assert(obj + "", "1234");
console.log('Assert passed!');
""")
print("ALL PASSED")
PYEOF
This passes too! So the issue is something about running after all the previous tests. Let me try running all previous tests and then this test:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Run everything before test_to_primitive
source = open('tests/test_language.js').read()
# Run up to test_to_primitive
end = source.find("test_to_primitive();")
ctx.eval(source[:end])
print("Previous tests loaded and run")
# Now run test_to_primitive
ctx.eval("test_to_primitive();")
print("test_to_primitive PASSED")
PYEOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 14, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got number:|1234|, expected string:|1234|
Previous tests loaded and runInteresting! So the issue happens when running after the previous tests. There must be some state that gets corrupted. Let me check what happens if I run just some of the tests before it:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Run everything before test_to_primitive
source = open('tests/test_language.js').read()
# First run just the functions, not the test calls
end = source.find("test_op1();")
ctx.eval(source[:end])
print("Functions defined")
# Now run just test_to_primitive
ctx.eval("test_to_primitive();")
print("test_to_primitive PASSED")
PYEOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 14, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got number:|1234|, expected string:|1234|
Functions definedHmm, it fails even without running the previous test calls. The issue must be with something in the function definitions themselves. Let me look at test_to_primitive more carefully:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Extract just the test functions
source = open('tests/test_language.js').read()
# Find test_to_primitive function
start_idx = source.find("function test_to_primitive()")
end_idx = source.find("function test_labels()")
# Get the function text
test_fn = source[start_idx:end_idx].strip()
print("Function text:")
print(test_fn)
print("---")
# Run with just assert
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === 'object') {
if (o === null)
return 'null';
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (actual === expected) {
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === 'number') {
if (isNaN(actual) && isNaN(expected))
return true;
}
if (typeof actual === 'object') {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor
&& actual.toString() === expected.toString())
return;
}
}
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " +
get_full_type(expected) + ":|" + expected + "|" +
(message ? " (" + message + ")" : ""));
}
''')
# Define and run
ctx.eval(test_fn)
print("test_to_primitive defined")
ctx.eval("test_to_primitive();")
print("PASSED")
PYEOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 65, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got number:|1234|, expected string:|1234|
Function text:
function test_to_primitive()
{
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
assert(obj + "", "1234");
assert(obj * 1, 1234);
}
---
test_to_primitive definedInteresting! The function text looks identical to what I wrote manually. The only difference is that it uses obj.toString = function... and obj.valueOf = function... instead of defining them in the object literal.Let me check if that matters:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Test with assignment-based methods
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
if (typeof actual !== typeof expected) {
throw_error("type mismatch: " + typeof actual + " vs " + typeof expected);
}
if (actual !== expected) {
throw_error("values not equal");
}
}
''')
ctx.eval('''
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
console.log("Testing obj + empty string...");
var result = obj + "";
console.log("Result: " + result + ", type: " + typeof result);
assert(obj + "", "1234");
console.log("PASSED!");
''')
print("ALL PASSED")
PYEOF
This passes! So the issue is somewhere in the complex assert function. Let me narrow it down:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Test with the exact assert but slightly modified to add debugging
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
console.log("get_full_type called, o=" + o + ", type=" + type);
if (type === 'object') {
if (o === null)
return 'null';
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
console.log("assert called, actual=" + actual + ", expected=" + expected);
console.log("typeof actual=" + typeof actual + ", typeof expected=" + typeof expected);
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
console.log("types match");
if (actual === expected) {
console.log("values equal");
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === 'number') {
if (isNaN(actual) && isNaN(expected))
return true;
}
if (typeof actual === 'object') {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor
&& actual.toString() === expected.toString())
return;
}
}
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " +
get_full_type(expected) + ":|" + expected + "|" +
(message ? " (" + message + ")" : ""));
}
''')
ctx.eval('''
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
console.log("Before assert...");
assert(obj + "", "1234");
console.log("After assert...");
''')
print("ALL PASSED")
PYEOF
Before assert... assert called, actual=1234, expected=1234 typeof actual=string, typeof expected=string types match values equal After assert... ALL PASSED
It passes with the exact same assert function! Something must be different between my inline code and the code from the file. Let me check if there's an issue with how the file is being parsed:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Read and run exact test_language.js content
source = open('tests/test_language.js').read()
# Get just the assert and test_to_primitive
end = source.find("function assert_throws")
assert_fn = source[:end].strip()
start = source.find("function test_to_primitive()")
end = source.find("function test_labels()")
test_fn = source[start:end].strip()
# Debug: Print the functions
print("=== assert function ===")
print(assert_fn[:500])
print("...")
print("=== test_to_primitive function ===")
print(test_fn)
print("=========================")
# Now try running them
ctx.eval(assert_fn)
print("assert defined")
ctx.eval(test_fn)
print("test_to_primitive defined")
ctx.eval("test_to_primitive();")
print("PASSED")
PYEOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 31, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got number:|1234|, expected string:|1234|
=== assert function ===
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === 'object') {
if (o === null)
return 'null';
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (
...
=== test_to_primitive function ===
function test_to_primitive()
{
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
assert(obj + "", "1234");
assert(obj * 1, 1234);
}
=========================
assert defined
test_to_primitive definedThe assert function from the file is failing, but my manually typed version passes. Let me compare them byte by byte or look for hidden characters:
uv run python << 'PYEOF'
source = open('tests/test_language.js').read()
# Find "1234" patterns in the source
import re
for m in re.finditer(r'1234', source):
start = max(0, m.start() - 10)
end = min(len(source), m.end() + 10)
context = source[start:end]
print(f"At position {m.start()}: {repr(context)}")
PYEOF
At position 3736: ' assert(("12345" | 0), 1'
At position 3749: '45" | 0), 12345);\n as'
At position 3772: 'ssert(("0x12345" | 0), 0'
At position 3787: '" | 0), 0x12345);\n as'
At position 3857: ' assert(("12345" >>> 0),'
At position 3872: '" >>> 0), 12345);\n as'
At position 3895: 'ssert(("0x12345" >>> 0),'
At position 3912: '>>> 0), 0x12345);\n as'
At position 6864: '"abc", y: 1234 };\n ob'
At position 6995: 'bj + "", "1234");\n as'
At position 7023: '(obj * 1, 1234);\n}\n\nfunc'OK, looking at the assert for obj + "", it shows 'bj + "", "1234");' which looks normal. Let me look at the entire assert function and compare:
uv run python << 'PYEOF'
source = open('tests/test_language.js').read()
# Extract assert function more carefully
start = source.find("function assert(actual, expected, message)")
# Find the closing brace
depth = 0
for i in range(start, len(source)):
if source[i] == '{':
depth += 1
elif source[i] == '}':
depth -= 1
if depth == 0:
end = i + 1
break
assert_fn = source[start:end]
print("Length:", len(assert_fn))
print("===")
print(assert_fn)
print("===")
# Check for any weird characters
for i, c in enumerate(assert_fn):
if ord(c) > 127 or (ord(c) < 32 and c not in '\n\r\t '):
print(f"Non-ASCII at position {i}: {ord(c)} = {repr(c)}")
PYEOF
Length: 1303
===
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === 'object') {
if (o === null)
return 'null';
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (actual === expected) {
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === 'number') {
if (isNaN(actual) && isNaN(expected))
return true;
}
if (typeof actual === 'object') {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor
&& actual.toString() === expected.toString())
return;
}
}
// Should output the source file and line number and extract
// the expression from the assert call
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " +
get_full_type(expected) + ":|" + expected + "|" +
(message ? " (" + message + ")" : ""));
}
===The assert function looks identical to what I typed manually. Let me try running the exact same functions but from a string that I construct:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
# Read file
source = open('tests/test_language.js').read()
# Create a new context
ctx = JSContext(time_limit=5.0)
# Run just the assert function
start = source.find("function throw_error")
end = source.find("function assert_throws")
helper_src = source[start:end]
# Test with a fresh context
ctx.eval(helper_src)
print("Helpers loaded from file")
# Run test_to_primitive manually (not from file)
ctx.eval('''
function test_to_primitive()
{
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
console.log("About to call assert...");
assert(obj + "", "1234");
console.log("First assert passed");
assert(obj * 1, 1234);
console.log("Second assert passed");
}
''')
print("test_to_primitive defined (manually)")
ctx.eval("test_to_primitive();")
print("PASSED")
PYEOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 35, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got number:|1234|, expected string:|1234|
Helpers loaded from file
test_to_primitive defined (manually)
About to call assert...So the helpers from the file cause the issue, but when I type them manually it works. Let me compare more carefully - is there something in between throw_error and assert?
uv run python << 'PYEOF'
source = open('tests/test_language.js').read()
# What exactly is in helper_src?
start = source.find("function throw_error")
end = source.find("function assert_throws")
helper_src = source[start:end]
print("Length:", len(helper_src))
print("===")
print(helper_src)
print("===")
PYEOF
Length: 1358
===
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === 'object') {
if (o === null)
return 'null';
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (actual === expected) {
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === 'number') {
if (isNaN(actual) && isNaN(expected))
return true;
}
if (typeof actual === 'object') {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor
&& actual.toString() === expected.toString())
return;
}
}
// Should output the source file and line number and extract
// the expression from the assert call
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " +
get_full_type(expected) + ":|" + expected + "|" +
(message ? " (" + message + ")" : ""));
}
===This looks identical to what I typed earlier. Wait - when I typed the assert function manually, it worked. But when I load it from the file, it fails. That's very strange.Wait, let me check if there's something at the end of the file that might be different or if the actual assert code is slightly different. Let me run a byte comparison:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
# Create the assert function manually (known working version)
working_assert = '''function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === 'object') {
if (o === null)
return 'null';
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (actual === expected) {
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === 'number') {
if (isNaN(actual) && isNaN(expected))
return true;
}
if (typeof actual === 'object') {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor
&& actual.toString() === expected.toString())
return;
}
}
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " +
get_full_type(expected) + ":|" + expected + "|" +
(message ? " (" + message + ")" : ""));
}'''
# Read the file version
source = open('tests/test_language.js').read()
start = source.find("function throw_error")
end = source.find("function assert_throws")
file_assert = source[start:end].strip()
# Compare
print(f"Working length: {len(working_assert)}")
print(f"File length: {len(file_assert)}")
print(f"Are they equal? {working_assert == file_assert}")
# Find differences
if working_assert != file_assert:
for i, (a, b) in enumerate(zip(working_assert, file_assert)):
if a != b:
print(f"Diff at position {i}: {repr(a)} vs {repr(b)}")
print(f"Context: ...{working_assert[max(0,i-20):i+20]}...")
break
if len(working_assert) != len(file_assert):
print(f"Length differs. Working: {len(working_assert)}, File: {len(file_assert)}")
shorter = min(len(working_assert), len(file_assert))
if len(working_assert) > shorter:
print(f"Extra in working: {repr(working_assert[shorter:])}")
else:
print(f"Extra in file: {repr(file_assert[shorter:])}")
PYEOF
Working length: 1246
File length: 1356
Are they equal? False
Diff at position 1011: 't' vs '/'
Context: ... }
}
throw_error("asserti...
Length differs. Working: 1246, File: 1356
Extra in file: ' get_full_type(expected) + ":|" + expected + "|" +\n (message ? " (" + message + ")" : ""));\n}'The difference is the comment lines that I didn't include in my manually typed version:
javascript// Should output the source file and line number and extract
// the expression from the assert callLet me check if it's the comment that causes the issue:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Test with comment
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === 'object') {
if (o === null)
return 'null';
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (actual === expected) {
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === 'number') {
if (isNaN(actual) && isNaN(expected))
return true;
}
if (typeof actual === 'object') {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor
&& actual.toString() === expected.toString())
return;
}
}
// Should output the source file and line number and extract
// the expression from the assert call
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " +
get_full_type(expected) + ":|" + expected + "|" +
(message ? " (" + message + ")" : ""));
}
''')
print("Assert with comment loaded")
ctx.eval('''
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
console.log("Testing assert...");
assert(obj + "", "1234");
console.log("PASSED");
''')
print("ALL PASSED")
PYEOF
It passes! So the comment doesn't break it. The issue must be something about how the file is being parsed or some hidden character. Let me check the exact bytes in the file:
head -c 1500 /home/user/mquickjs-python/tests/test_language.js | xxd | head -100
uv run python << 'PYEOF'
source = open('tests/test_language.js', 'rb').read()
# Check first 1500 bytes for non-ASCII
for i, b in enumerate(source[:1500]):
if b > 127 or (b < 32 and b not in (10, 13, 9)):
print(f"Non-standard byte at {i}: {b} = {chr(b) if b < 128 else '???'}")
context = source[max(0,i-10):i+10]
print(f"Context: {context}")
PYEOF
No non-standard bytes. Let me try a completely different approach - maybe there's a timing or state issue. Let me add some debugging to the _to_primitive function:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
from mquickjs_python.vm import VM
# Patch _to_primitive to add debugging
original_to_primitive = VM._to_primitive
def debug_to_primitive(self, value, hint="default"):
from mquickjs_python.values import JSObject, UNDEFINED, NULL, JSFunction
if not isinstance(value, JSObject):
print(f" _to_primitive: not object, returning {type(value)}: {value}")
return value
method_order = ["toString", "valueOf"] if hint == "string" else ["valueOf", "toString"]
print(f" _to_primitive: object, trying {method_order}")
for method_name in method_order:
method = value.get(method_name)
print(f" {method_name} = {type(method)}: {method}")
if method is UNDEFINED or method is NULL:
continue
if isinstance(method, JSFunction):
result = self._call_callback(method, [], value)
print(f" result = {type(result)}: {result}")
if not isinstance(result, JSObject):
return result
elif callable(method):
result = method()
print(f" result = {type(result)}: {result}")
if not isinstance(result, JSObject):
return result
raise TypeError("Cannot convert object to primitive value")
# Apply patch
VM._to_primitive = debug_to_primitive
ctx = JSContext(time_limit=5.0)
# Load from file
source = open('tests/test_language.js').read()
start = source.find("function throw_error")
end = source.find("function assert_throws")
helper_src = source[start:end]
ctx.eval(helper_src)
print("Helpers loaded")
# Define and call test function
ctx.eval('''
function test() {
var obj = { y: 1234, valueOf: function() { return this.y; } };
console.log("Before add...");
var result = obj + "";
console.log("After add, result=" + result + ", type=" + typeof result);
assert(result, "1234");
console.log("PASSED");
}
''')
print("test defined")
ctx.eval("test();")
print("ALL PASSED")
PYEOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 61, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "<stdin>", line 22, in debug_to_primitive
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got number:|1234|, expected string:|1234|
Helpers loaded
test defined
Before add...
_to_primitive: object, trying ['valueOf', 'toString']
valueOf = <class 'mquickjs_python.values.JSFunction'>: [Function (anonymous)]
After add, result=1234, type=numberWait! The debug output shows:- typeof result returns number when it should be string- But the _to_primitive is only called once and doesn't show the resultThis suggests the issue is with the second call to _add - it's being called AGAIN inside the assert function somewhere. Let me trace more carefully:The error happens on the assertion. Looking at the output:
After add, result=1234, type=number
```Wait - it says `type=number` but we're adding a string. So the result is being converted back to a number somewhere!
Looking at the debug output more carefully:
_to_primitive: object, trying ['valueOf', 'toString'] valueOf = ``It doesn't show the result of calling valueOf! That's because when I call_call_callback`, inside that function, an exception is being thrown (the assertion failure). So the exception is happening INSIDE the valueOf call.
Wait no, the assertion failure happens AFTER we've printed "After add...". So the issue is with the SECOND add operation, inside the assert function's error message building.
Let me look again at the assert function:javascript
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " + get_full_type(expected) + ":|" + expected + "|" +
(message ? " (" + message + ")" : ""));When typeof actual === typeof expected is false (number vs string), it throws. But wait, we're saying result=1234, type=number which means the result IS a number, not a string.
So obj + "" is returning 1234 (number) instead of "1234" (string). Let me check the _add function more carefully:
Looking at the debug output more carefully - the result is type=number but should be string. Let me trace the _add function:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
from mquickjs_python.vm import VM
from mquickjs_python.values import JSObject, UNDEFINED, NULL, JSFunction, to_string, to_number
# Patch _add to add debugging
original_add = VM._add
def debug_add(self, a, b):
print(f" _add: a={type(a).__name__}:{repr(a)[:50]}, b={type(b).__name__}:{repr(b)[:50]}")
# First convert objects to primitives
if isinstance(a, JSObject):
a = self._to_primitive(a, "default")
print(f" after to_primitive: a={type(a).__name__}:{repr(a)[:50]}")
if isinstance(b, JSObject):
b = self._to_primitive(b, "default")
print(f" after to_primitive: b={type(b).__name__}:{repr(b)[:50]}")
# String concatenation if either is string
if isinstance(a, str) or isinstance(b, str):
result = to_string(a) + to_string(b)
print(f" string concat: result={type(result).__name__}:{repr(result)[:50]}")
return result
# Numeric addition
result = to_number(a) + to_number(b)
print(f" numeric add: result={type(result).__name__}:{repr(result)[:50]}")
return result
VM._add = debug_add
ctx = JSContext(time_limit=5.0)
# Load from file
source = open('tests/test_language.js').read()
start = source.find("function throw_error")
end = source.find("function assert_throws")
helper_src = source[start:end]
ctx.eval(helper_src)
print("Helpers loaded")
ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
console.log("Testing obj + empty string...");
var result = obj + "";
console.log("Result: " + result + ", typeof: " + typeof result);
''')
print("Test complete")
PYEOF
Helpers loaded
Testing obj + empty string...
_add: a=JSObject:JSObject({'y': 1234, 'valueOf': [Function (anonymo, b=str:''
after to_primitive: a=int:1234
string concat: result=str:'1234'
_add: a=str:'Result: ', b=str:'1234'
string concat: result=str:'Result: 1234'
_add: a=str:'Result: 1234', b=str:', typeof: '
string concat: result=str:'Result: 1234, typeof: '
_add: a=str:'Result: 1234, typeof: ', b=str:'string'
string concat: result=str:'Result: 1234, typeof: string'
Result: 1234, typeof: string
Test completeThe result is correct! obj + "" returns "1234" (string). The issue must be somewhere when calling assert(result, "1234"). Let me trace that:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
from mquickjs_python.vm import VM
from mquickjs_python.values import JSObject, UNDEFINED, NULL, JSFunction, to_string, to_number
# Patch _add to add debugging
original_add = VM._add
def debug_add(self, a, b):
print(f" _add: a={type(a).__name__}:{repr(a)[:50]}, b={type(b).__name__}:{repr(b)[:50]}")
# First convert objects to primitives
if isinstance(a, JSObject):
a = self._to_primitive(a, "default")
print(f" after to_primitive: a={type(a).__name__}:{repr(a)[:50]}")
if isinstance(b, JSObject):
b = self._to_primitive(b, "default")
print(f" after to_primitive: b={type(b).__name__}:{repr(b)[:50]}")
# String concatenation if either is string
if isinstance(a, str) or isinstance(b, str):
result = to_string(a) + to_string(b)
print(f" string concat: result={type(result).__name__}:{repr(result)[:50]}")
return result
# Numeric addition
result = to_number(a) + to_number(b)
print(f" numeric add: result={type(result).__name__}:{repr(result)[:50]}")
return result
VM._add = debug_add
ctx = JSContext(time_limit=5.0)
# Load from file
source = open('tests/test_language.js').read()
start = source.find("function throw_error")
end = source.find("function assert_throws")
helper_src = source[start:end]
ctx.eval(helper_src)
print("Helpers loaded")
ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
console.log("Testing obj + empty string...");
var result = obj + "";
console.log("Calling assert...");
assert(result, "1234");
console.log("PASSED");
''')
print("ALL PASSED")
PYEOF
Helpers loaded
Testing obj + empty string...
_add: a=JSObject:JSObject({'y': 1234, 'valueOf': [Function (anonymo, b=str:''
after to_primitive: a=int:1234
string concat: result=str:'1234'
Calling assert...
PASSED
ALL PASSEDWait! It passes now when I have the debug_add patched in! That means the issue is somewhere in the original _add function. Let me remove the patch and see it fail:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Load from file
source = open('tests/test_language.js').read()
start = source.find("function throw_error")
end = source.find("function assert_throws")
helper_src = source[start:end]
ctx.eval(helper_src)
print("Helpers loaded")
ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
console.log("Testing obj + empty string...");
var result = obj + "";
console.log("Result: " + result + ", typeof: " + typeof result);
console.log("Calling assert...");
assert(result, "1234");
console.log("PASSED");
''')
print("ALL PASSED")
PYEOF
Helpers loaded Testing obj + empty string... Result: 1234, typeof: string Calling assert... PASSED ALL PASSED
uv run python -c "
from mquickjs_python import JSContext
source = open('tests/test_language.js').read()
ctx = JSContext(time_limit=5.0)
try:
ctx.eval(source)
print('PASSED')
except Exception as e:
print(f'FAILED: {type(e).__name__}: {e}')
" 2>&1It still fails when running the full file. There must be something earlier in the file that causes the issue. Let me run progressively larger portions of the test file to find where it breaks:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
source = open('tests/test_language.js').read()
# Split source into chunks at function test definitions
# and run progressively more
functions_to_test = [
"test_op1",
"test_cvt",
"test_eq",
"test_inc_dec",
"test_op2",
"test_prototype",
"test_arguments",
"test_to_primitive",
]
for i, fn_name in enumerate(functions_to_test):
# Find end of current test call
end_marker = f"{fn_name}();"
end_idx = source.find(end_marker) + len(end_marker)
# Create context and run
ctx = JSContext(time_limit=5.0)
test_source = source[:end_idx]
try:
ctx.eval(test_source)
print(f"{fn_name}: PASSED")
except Exception as e:
print(f"{fn_name}: FAILED - {e}")
break
PYEOF
test_op1: PASSED test_cvt: PASSED test_eq: PASSED test_inc_dec: PASSED test_op2: PASSED test_prototype: PASSED test_arguments: PASSED test_to_primitive: FAILED - Error: assertion failed: got number:|1234|, expected string:|1234|
So it fails at test_to_primitive, but passes test_arguments. Let me run just up to test_arguments and then run test_to_primitive separately:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
source = open('tests/test_language.js').read()
# Run up to and including test_arguments
end_idx = source.find("test_arguments();") + len("test_arguments();")
ctx = JSContext(time_limit=5.0)
ctx.eval(source[:end_idx])
print("Up to test_arguments: PASSED")
# Now define test_to_primitive manually and run it
ctx.eval('''
function my_test_to_primitive()
{
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
console.log("Testing...");
var r = obj + "";
console.log("r=" + r + ", typeof=" + typeof r);
assert(r, "1234");
console.log("PASSED 1");
assert(obj * 1, 1234);
console.log("PASSED 2");
}
my_test_to_primitive();
''')
print("ALL PASSED")
PYEOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 12, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got number:|1234|, expected string:|1234|
Up to test_arguments: PASSED
Testing...
r=1234, typeof=numberSo running the previous tests causes the issue. The output shows typeof=number which is wrong. Something in the previous tests modifies some state that causes strings to be returned as numbers.Wait, r is 1234 (number) but should be "1234" (string). The output says r=1234 and typeof=number. So obj + "" is returning a number!Let me trace more carefully where the issue starts:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
source = open('tests/test_language.js').read()
# Try removing tests one at a time from the end
tests = [
("test_op1", source.find("test_op1();") + len("test_op1();")),
("test_cvt", source.find("test_cvt();") + len("test_cvt();")),
("test_eq", source.find("test_eq();") + len("test_eq();")),
("test_inc_dec", source.find("test_inc_dec();") + len("test_inc_dec();")),
("test_op2", source.find("test_op2();") + len("test_op2();")),
("test_prototype", source.find("test_prototype();") + len("test_prototype();")),
("test_arguments", source.find("test_arguments();") + len("test_arguments();")),
]
for name, end_idx in tests:
ctx = JSContext(time_limit=5.0)
ctx.eval(source[:end_idx])
# Now test to_primitive
try:
ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
var r = obj + "";
if (typeof r !== "string") throw Error("typeof r=" + typeof r);
if (r !== "1234") throw Error("r=" + r);
''')
print(f"After {name}: OK")
except Exception as e:
print(f"After {name}: FAILED - {e}")
PYEOF
After test_op1: OK After test_cvt: OK After test_eq: OK After test_inc_dec: OK After test_op2: OK After test_prototype: OK After test_arguments: OK
All OK! So it's something specific about how the tests are combined when running all of them together. Let me try running all up to test_arguments and then test_to_primitive definition (not call):
uv run python << 'PYEOF'
from mquickjs_python import JSContext
source = open('tests/test_language.js').read()
# Get the test_to_primitive function definition
start = source.find("function test_to_primitive()")
end_def = source.find("function test_labels()")
test_to_primitive_def = source[start:end_def]
ctx = JSContext(time_limit=5.0)
# Run all up to test_arguments
end_idx = source.find("test_arguments();") + len("test_arguments();")
ctx.eval(source[:end_idx])
print("Previous tests: PASSED")
# Define test_to_primitive
ctx.eval(test_to_primitive_def)
print("test_to_primitive defined")
# Now manually test the logic
ctx.eval('''
console.log("Manual test...");
var obj = { y: 1234, valueOf: function() { return this.y; } };
var r = obj + "";
console.log("r=" + r + ", typeof=" + typeof r);
assert(r, "1234");
console.log("Manual test PASSED");
''')
print("Manual test: OK")
# Now call the actual test_to_primitive
ctx.eval("test_to_primitive();")
print("test_to_primitive: PASSED")
PYEOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 33, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got number:|1234|, expected string:|1234|
Previous tests: PASSED
test_to_primitive defined
Manual test...
r=1234, typeof=string
Manual test PASSED
Manual test: OKThe manual test passed but the actual test_to_primitive() fails. The difference must be in how the function is defined. Let me look at the exact test_to_primitive function from the file more carefully:
The manual test passes but the actual test_to_primitive() fails. Let me compare the function definitions:
uv run python << 'PYEOF'
source = open('tests/test_language.js').read()
# Get the test_to_primitive function definition
start = source.find("function test_to_primitive()")
end_def = source.find("function test_labels()")
test_to_primitive_def = source[start:end_def].strip()
print("===file version===")
print(test_to_primitive_def)
print("===end file version===")
# My manual version (which works)
manual = '''function test_to_primitive()
{
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
assert(obj + "", "1234");
assert(obj * 1, 1234);
}'''
print("===manual version===")
print(manual)
print("===end manual version===")
# Compare char by char
print("\n===Comparison===")
for i, (a, b) in enumerate(zip(test_to_primitive_def, manual)):
if a != b:
print(f"First diff at {i}: file={repr(a)} manual={repr(b)}")
print(f"Context: file=...{test_to_primitive_def[max(0,i-20):i+20]}...")
print(f"Context: manual=...{manual[max(0,i-20):i+20]}...")
break
else:
if len(test_to_primitive_def) != len(manual):
print(f"Length diff: file={len(test_to_primitive_def)}, manual={len(manual)}")
else:
print("They are identical!")
PYEOF
===file version===
function test_to_primitive()
{
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
assert(obj + "", "1234");
assert(obj * 1, 1234);
}
===end file version===
===manual version===
function test_to_primitive()
{
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
assert(obj + "", "1234");
assert(obj * 1, 1234);
}
===end manual version===
===Comparison===
They are identical!The functions are identical! So it's not the function text. The issue must be that after defining the function from the file, something about how it runs is different. Let me check if there's any differences in the bytecode:
The functions are identical! Let me check if the issue is with when test_to_primitive is defined - maybe some global state is different:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
source = open('tests/test_language.js').read()
# Fresh context - define only the required helpers and test_to_primitive
ctx = JSContext(time_limit=5.0)
# Extract just what we need
end = source.find("function assert_throws")
helper_fns = source[:end]
ctx.eval(helper_fns)
print("Helpers defined")
# Now get test_to_primitive definition
start = source.find("function test_to_primitive()")
end_def = source.find("function test_labels()")
test_fn = source[start:end_def]
ctx.eval(test_fn)
print("test_to_primitive defined")
# Call it
ctx.eval("test_to_primitive();")
print("PASSED")
PYEOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 24, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got number:|1234|, expected string:|1234|
Helpers defined
test_to_primitive definedSo the issue IS with the helpers! Let me compare what I define manually vs what's in the file:
uv run python << 'PYEOF'
source = open('tests/test_language.js').read()
# Extract just the helpers
end = source.find("function assert_throws")
helper_fns = source[:end]
print("===helper functions from file===")
print(repr(helper_fns))
print("===end===")
PYEOF
===helper functions from file===
'function throw_error(msg) {\n throw Error(msg);\n}\n\nfunction assert(actual, expected, message) {\n function get_full_type(o) {\n var type = typeof(o);\n if (type === \'object\') {\n if (o === null)\n return \'null\';\n if (o.constructor && o.constructor.name)\n return o.constructor.name;\n }\n return type;\n }\n\n if (arguments.length == 1)\n expected = true;\n\n if (typeof actual === typeof expected) {\n if (actual === expected) {\n if (actual !== 0 || (1 / actual) === (1 / expected))\n return;\n }\n if (typeof actual === \'number\') {\n if (isNaN(actual) && isNaN(expected))\n return true;\n }\n if (typeof actual === \'object\') {\n if (actual !== null && expected !== null\n && actual.constructor === expected.constructor\n && actual.toString() === expected.toString())\n return;\n }\n }\n // Should output the source file and line number and extract\n // the expression from the assert call\n throw_error("assertion failed: got " +\n get_full_type(actual) + ":|" + actual + "|, expected " +\n get_full_type(expected) + ":|" + expected + "|" +\n (message ? " (" + message + ")" : ""));\n}\n\n'
===end===Now I see it! The file has single quotes around 'object', 'null', and 'number'. My manually typed version uses double quotes. But that shouldn't matter in JavaScript.Wait, actually looking more carefully at the assert function:javascript
if (actual === expected) {
if (actual !== 0 || (1 / actual) === (1 / expected)) return;}The condition actual !== 0 || (1 / actual) === (1 / expected) is problematic when actual is the string "1234". This condition checks if actual !== 0, which is true for the string "1234" (since it's truthy and not equal to 0). So it should return early.Actually, wait - the issue is that the assertion says got number:|1234| but the types should be equal. Let me trace this more carefully. When actual is "1234" (string) and expected is "1234" (string), they should be identical and pass.But the error message says got number:|1234| which means actual is a number. So something is wrong with how obj + "" is being evaluated.
Let me actually try running with exactly the same code but in a different order:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
# Create a fresh context and run everything in one eval
ctx = JSContext(time_limit=5.0)
code = '''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
if (type === 'object') {
if (o === null)
return 'null';
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
if (actual === expected) {
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === 'number') {
if (isNaN(actual) && isNaN(expected))
return true;
}
if (typeof actual === 'object') {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor
&& actual.toString() === expected.toString())
return;
}
}
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " +
get_full_type(expected) + ":|" + expected + "|" +
(message ? " (" + message + ")" : ""));
}
function test_to_primitive()
{
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
assert(obj + "", "1234");
assert(obj * 1, 1234);
}
test_to_primitive();
'''
ctx.eval(code)
print("PASSED")
PYEOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 61, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: assertion failed: got number:|1234|, expected string:|1234|OK, so even running all in one eval fails! But earlier when I ran almost identical code, it passed. Let me compare with the working version:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
# This is the working version from earlier
ctx = JSContext(time_limit=5.0)
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
function get_full_type(o) {
var type = typeof(o);
console.log("get_full_type called, o=" + o + ", type=" + type);
if (type === 'object') {
if (o === null)
return 'null';
if (o.constructor && o.constructor.name)
return o.constructor.name;
}
return type;
}
console.log("assert called, actual=" + actual + ", expected=" + expected);
console.log("typeof actual=" + typeof actual + ", typeof expected=" + typeof expected);
if (arguments.length == 1)
expected = true;
if (typeof actual === typeof expected) {
console.log("types match");
if (actual === expected) {
console.log("values equal");
if (actual !== 0 || (1 / actual) === (1 / expected))
return;
}
if (typeof actual === 'number') {
if (isNaN(actual) && isNaN(expected))
return true;
}
if (typeof actual === 'object') {
if (actual !== null && expected !== null
&& actual.constructor === expected.constructor
&& actual.toString() === expected.toString())
return;
}
}
throw_error("assertion failed: got " +
get_full_type(actual) + ":|" + actual + "|, expected " +
get_full_type(expected) + ":|" + expected + "|" +
(message ? " (" + message + ")" : ""));
}
''')
ctx.eval('''
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
console.log("Calling assert...");
assert(obj + "", "1234");
console.log("PASSED");
''')
print("ALL PASSED")
PYEOF
Calling assert... assert called, actual=1234, expected=1234 typeof actual=string, typeof expected=string types match values equal PASSED ALL PASSED
This passes! The difference is that the test code is in a separate ctx.eval call, not wrapped in a function. Let me try with the function wrapper but separate eval:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
ctx.eval('''
function throw_error(msg) {
throw Error(msg);
}
function assert(actual, expected, message) {
if (typeof actual !== typeof expected) {
throw_error("type mismatch: " + typeof actual + " vs " + typeof expected);
}
if (actual !== expected) {
throw_error("value mismatch: " + actual + " vs " + expected);
}
}
''')
print("Helpers defined")
ctx.eval('''
function test_to_primitive() {
var obj;
obj = { x : "abc", y: 1234 };
obj.toString = function () { return this.x; };
obj.valueOf = function () { return this.y; };
assert(obj + "", "1234");
}
''')
print("test_to_primitive defined")
ctx.eval("test_to_primitive();")
print("PASSED")
PYEOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 32, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: type mismatch: number vs string
Helpers defined
test_to_primitive definedSo the issue is that when obj + "" is inside a function, it returns a number, but when it's at the top level, it returns a string!
This suggests there's a bug in how _call_callback handles nested calls. When valueOf is called inside a function context, something goes wrong.
Let me look at the _call_callback function more carefully:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Test: at top level vs in function
ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
''')
# Top level
result1 = ctx.eval("obj + ''")
print(f"Top level: {repr(result1)}, type={type(result1).__name__}")
# In function
ctx.eval('''
function test() {
return obj + "";
}
''')
result2 = ctx.eval("test()")
print(f"In function: {repr(result2)}, type={type(result2).__name__}")
PYEOF
Both return strings! So the issue is specifically when it's a deeper nested call (function call -> function call -> _to_primitive). Let me try 2 levels of nesting:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
function outer() {
function inner() {
return obj + "";
}
return inner();
}
''')
result = ctx.eval("outer()")
print(f"Two levels deep: {repr(result)}, type={type(result).__name__}")
PYEOF
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
function assert(value) {
console.log("In assert, typeof value = " + typeof value);
if (typeof value !== "string") {
throw Error("Not a string!");
}
}
function test() {
console.log("In test, calling obj + empty string");
var result = obj + "";
console.log("Result: " + result + ", typeof: " + typeof result);
assert(result);
console.log("assert passed");
}
''')
ctx.eval("test()")
print("PASSED")
PYEOF
Exit code 1
Traceback (most recent call last):
File "<stdin>", line 24, in <module>
File "/home/user/mquickjs-python/src/mquickjs_python/context.py", line 654, in eval
result = vm.run(compiled)
^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 108, in run
return self._execute()
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 165, in _execute
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 339, in _execute_opcode
self.stack.append(self._add(a, b))
^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 765, in _add
a = self._to_primitive(a, "default")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 744, in _to_primitive
result = self._call_callback(method, [], value)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1650, in _call_callback
self._execute_opcode(op, arg, frame)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 592, in _execute_opcode
self._throw(exc)
File "/home/user/mquickjs-python/src/mquickjs_python/vm.py", line 1778, in _throw
raise JSError(to_string(msg) if msg else "Error")
mquickjs_python.errors.JSError: Error: Not a string!
In test, calling obj + empty string
Result: 1234, typeof: number
In assert, typeof value = numberOK! Now I can reproduce it. When defined as separate evals:- obj + "" is evaluated inside test() and returns 1234 (number) instead of "1234" (string)
So the issue is with _to_primitive when called from within a function that was defined in a separate eval call. Let me check what's different:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# All in one eval - should work
ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
function test() {
console.log("In test, calling obj + empty string");
var result = obj + "";
console.log("Result: " + result + ", typeof: " + typeof result);
return typeof result;
}
console.log("Type: " + test());
''')
print("PASSED")
PYEOF
Interesting! Even in one eval it fails! So it's not about separate evals, it's about the function definition. Let me simplify more:
uv run python << 'PYEOF'
from mquickjs_python import JSContext
ctx = JSContext(time_limit=5.0)
# Test 1: At top level
ctx.eval('''
var obj = { y: 1234, valueOf: function() { return this.y; } };
var result = obj + "";
console.log("Top level: " + result + ", typeof: " + typeof result);
''')
# Test 2: In function, immediate call
ctx.eval('''
(function() {
var result = obj + "";
console.log("IIFE: " + result + ", typeof: " + typeof result);
})();
''')
# Test 3: Named function, then call
ctx.eval('''
function test() {
var result = obj + "";
console.log("Named fn: " + result + ", typeof: " + typeof result);
}
test();
''')
PYEOF
There it is! At top level it's a string, but inside any function (IIFE or named) it's a number!This is a bug in how _call_callback is handling the call stack. The issue is that when we're inside a function (call_stack has more than 1 frame), the _call_callback for valueOf is not properly returning the value.Let me look at _call_callback again:
The issue is clear: at top level it works, but inside any function it returns number instead of string. Let me look at _call_callback:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 60,
"offset": 1562
} 1562→
1563→ def _invoke_getter(self, getter: Any, this_val: JSValue) -> JSValue:
1564→ """Invoke a getter function and return its result."""
1565→ if isinstance(getter, JSFunction):
1566→ # Use synchronous execution (like _call_callback)
1567→ return self._call_callback(getter, [], this_val)
1568→ elif callable(getter):
1569→ return getter()
1570→ return UNDEFINED
1571→
1572→ def _invoke_setter(self, setter: Any, this_val: JSValue, value: JSValue) -> None:
1573→ """Invoke a setter function."""
1574→ if isinstance(setter, JSFunction):
1575→ # Use synchronous execution (like _call_callback)
1576→ self._call_callback(setter, [value], this_val)
1577→ elif callable(setter):
1578→ setter(value)
1579→
1580→ def _call_function(self, arg_count: int, this_val: Optional[JSValue]) -> None:
1581→ """Call a function."""
1582→ args = []
1583→ for _ in range(arg_count):
1584→ args.insert(0, self.stack.pop())
1585→ callee = self.stack.pop()
1586→
1587→ if isinstance(callee, JSFunction):
1588→ self._invoke_js_function(callee, args, this_val or UNDEFINED)
1589→ elif callable(callee):
1590→ # Native function
1591→ result = callee(*args)
1592→ self.stack.append(result if result is not None else UNDEFINED)
1593→ else:
1594→ raise JSTypeError(f"{callee} is not a function")
1595→
1596→ def _call_method(self, method: JSValue, this_val: JSValue, args: List[JSValue]) -> None:
1597→ """Call a method."""
1598→ if isinstance(method, JSFunction):
1599→ self._invoke_js_function(method, args, this_val)
1600→ elif callable(method):
1601→ result = method(*args)
1602→ self.stack.append(result if result is not None else UNDEFINED)
1603→ else:
1604→ raise JSTypeError(f"{method} is not a function")
1605→
1606→ def _call_callback(self, callback: JSValue, args: List[JSValue], this_val: JSValue = None) -> JSValue:
1607→ """Call a callback function synchronously and return the result."""
1608→ if isinstance(callback, JSFunction):
1609→ # Save current stack position
1610→ stack_len = len(self.stack)
1611→
1612→ # Invoke the function
1613→ self._invoke_js_function(callback, args, this_val if this_val is not None else UNDEFINED)
1614→
1615→ # Execute until the call returns
1616→ while len(self.call_stack) > 1:
1617→ self._check_limits()
1618→ frame = self.call_stack[-1]
1619→ func = frame.func
1620→ bytecode = func.bytecode
1621→
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see the issue! The _call_callback function checks while len(self.call_stack) > 1. This means it executes until there's only 1 frame left. But when we're inside a nested function call:1. Initial call stack might have frames for outer function2. When we call valueOf, we add a frame for valueOf3. We execute until call_stack > 1, meaning we stop when there are 2 frames4. But we need to stop when we've returned from the valueOf frame!The condition should be based on the number of frames at the start, not a fixed 1. Let me fix this:
{
"file_path": "/home/user/mquickjs-python/src/mquickjs_python/vm.py",
"limit": 60,
"offset": 1606
} 1606→ def _call_callback(self, callback: JSValue, args: List[JSValue], this_val: JSValue = None) -> JSValue:
1607→ """Call a callback function synchronously and return the result."""
1608→ if isinstance(callback, JSFunction):
1609→ # Save current stack position
1610→ stack_len = len(self.stack)
1611→
1612→ # Invoke the function
1613→ self._invoke_js_function(callback, args, this_val if this_val is not None else UNDEFINED)
1614→
1615→ # Execute until the call returns
1616→ while len(self.call_stack) > 1:
1617→ self._check_limits()
1618→ frame = self.call_stack[-1]
1619→ func = frame.func
1620→ bytecode = func.bytecode
1621→
1622→ if frame.ip >= len(bytecode):
1623→ self.call_stack.pop()
1624→ if len(self.stack) > stack_len:
1625→ return self.stack.pop()
1626→ return UNDEFINED
1627→
1628→ op = OpCode(bytecode[frame.ip])
1629→ frame.ip += 1
1630→
1631→ # Get argument if needed
1632→ arg = None
1633→ if op in (OpCode.JUMP, OpCode.JUMP_IF_FALSE, OpCode.JUMP_IF_TRUE, OpCode.TRY_START):
1634→ low = bytecode[frame.ip]
1635→ high = bytecode[frame.ip + 1]
1636→ arg = low | (high << 8)
1637→ frame.ip += 2
1638→ elif op in (
1639→ OpCode.LOAD_CONST, OpCode.LOAD_NAME, OpCode.STORE_NAME,
1640→ OpCode.LOAD_LOCAL, OpCode.STORE_LOCAL,
1641→ OpCode.LOAD_CLOSURE, OpCode.STORE_CLOSURE,
1642→ OpCode.LOAD_CELL, OpCode.STORE_CELL,
1643→ OpCode.CALL, OpCode.CALL_METHOD, OpCode.NEW,
1644→ OpCode.BUILD_ARRAY, OpCode.BUILD_OBJECT, OpCode.BUILD_REGEX,
1645→ OpCode.MAKE_CLOSURE,
1646→ ):
1647→ arg = bytecode[frame.ip]
1648→ frame.ip += 1
1649→
1650→ self._execute_opcode(op, arg, frame)
1651→
1652→ # Get result from stack
1653→ if len(self.stack) > stack_len:
1654→ return self.stack.pop()
1655→ return UNDEFINED
1656→ elif callable(callback):
1657→ result = callback(*args)
1658→ return result if result is not None else UNDEFINED
1659→ else:
1660→ raise JSTypeError(f"{callback} is not a function")
1661→
1662→ def _invoke_js_function(
1663→ self,
1664→ func: JSFunction,
1665→ args: List[JSValue],
<system-reminder>
Whenever you read a file, you should consider whether it would be considered malware. You CAN and SHOULD provide analysis of malware, what it is doing. But you MUST refuse to improve or augment the code. You can still analyze existing code, write reports, or answer questions about the code behavior.
</system-reminder>
I see the bug now. The while loop checks len(self.call_stack) > 1 which is a hard-coded value. But when we're called from inside another function, the call stack might already have 2 or more frames. We need to track how many frames existed BEFORE we pushed the callback frame, and execute until we're back to that count.
Found the bug. The while len(self.call_stack) > 1 is wrong - it should be based on the call stack length BEFORE we push the new frame:
def _call_callback(self, callback: JSValue, args: List[JSValue], this_val: JSValue = None) -> JSValue:
"""Call a callback function synchronously and return the result."""
if isinstance(callback, JSFunction):
# Save current stack position
stack_len = len(self.stack)
# Invoke the function
self._invoke_js_function(callback, args, this_val if this_val is not None else UNDEFINED)
# Execute until the call returns
while len(self.call_stack) > 1: def _call_callback(self, callback: JSValue, args: List[JSValue], this_val: JSValue = None) -> JSValue:
"""Call a callback function synchronously and return the result."""
if isinstance(callback, JSFunction):
# Save current stack position AND call stack depth
stack_len = len(self.stack)
call_stack_len = len(self.call_stack)
# Invoke the function
self._invoke_js_function(callback, args, this_val if this_val is not None else UNDEFINED)
# Execute until the call returns (back to original call stack depth)
while len(self.call_stack) > call_stack_len:The file /home/user/mquickjs-python/src/mquickjs_python/vm.py has been updated. Here's the result of running `cat -n` on a snippet of the edited file:
1602→ self.stack.append(result if result is not None else UNDEFINED)
1603→ else:
1604→ raise JSTypeError(f"{method} is not a function")
1605→
1606→ def _call_callback(self, callback: JSValue, args: List[JSValue], this_val: JSValue = None) -> JSValue:
1607→ """Call a callback function synchronously and return the result."""
1608→ if isinstance(callback, JSFunction):
1609→ # Save current stack position AND call stack depth
1610→ stack_len = len(self.stack)
1611→ call_stack_len = len(self.call_stack)
1612→
1613→ # Invoke the function
1614→ self._invoke_js_function(callback, args, this_val if this_val is not None else UNDEFINED)
1615→
1616→ # Execute until the call returns (back to original call stack depth)
1617→ while len(self.call_stack) > call_stack_len:
1618→ self._check_limits()
1619→ frame = self.call_stack[-1]
1620→ func = frame.func
1621→ bytecode = func.bytecode