[mypyc] Fix crash on multiple nested decorated functions with same name#20666
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p-sawicki merged 4 commits intopython:masterfrom Jan 29, 2026
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JukkaL
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Thanks for the fix, one suggestion about another case to test.
| async def wrapper(*args, **kwargs) -> Any: | ||
| return get_multiplier() * await fn(*args, **kwargs) | ||
| else: | ||
| @functools.wraps(fn) |
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Can you also test this without using @functools_wraps? It might behave differently.
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good call, turns out the fix wasn't right for all cases so i have updated it and added another test.
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Some more test case ideas, since this area seems to be have bugs: can you also test cases where none of the conditional variants are decorated, or some of variants are decorated (all of these could include sync + a mix of async/sync functions).
JukkaL
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This happens when a nested function has different definitions in different condition branches. mypyc currently crashes in this case when calling
get_func_targetintransform_decoratorhttps://github.com/python/mypy/blob/master/mypyc/irbuild/function.py#L118.The
FuncDefobjects for the definitions after the first one will have theoriginal_defattribute set. This makesget_func_targetlookup this original def but it doesn't find it when the original def is a decorator because registers are only created forFuncDefs.Extracting a
FuncDeffrom the original decorator and looking it up instead fixes the crash.