`asyncio.Timeout.__aexit__` does not handle `BaseExceptionGroup`
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@gunyu1019 is already working on this.
Since Aug 15, 2025.
stdlib
topic-asyncio
type-bug
- Dominant language
- Python
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Description
Bug report
Bug description:
There may be a good reason for this I am not seeing, but in the asyncio.Timeout.__aexit__ handler, the exception group handling seems too narrow:
Given exc_val itself can be a BaseException and _insert_timeout_error takes a BaseException as an argument, I fail to see a reason not to check for superclass BaseExceptionGroup instead.
This no longer impacts me as I implemented what I was aiming for in a better way, but it still looks like a bug. Is it?
CPython versions tested on:
3.13
Operating systems tested on:
Linux
Linked PRs
- gh-137797
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