gh-81371: implementing checking async generator methods

[wrongnull]

This PR may fix #81371

• Issue: asyncio.iscoroutinefunction(<async_generator>.asend) returns False #81371

[bedevere-bot]

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[wrongnull]

Is there one certain way to define if callable returns awaitable? I mean it is possible to reimplement some logic in C. For instance callable can has special flag to this purpose. It's because I'm not sure if my patch handles all possible corner cases so maybe there are more subtle ones. So if the checked object was not declared with async def the only way to check this condition is brute force it manually, I guess.

[sobolevn]

Couple of thoughts:

1. There are other ways to do that. Flags, coroutine marks, etc. Why this one is the best one? (I am not an asyncio expert)
2. Is it a problem worth fixing at all?

[sobolevn]

May? Or does it? Please, also specify what the issue is. These are user-facing notes. It must be clear without a github link.

[wrongnull]

May? Or does it? Please, also specify what the issue is. These are user-facing notes. It must be clear without a github link.

I'm not 100% sure if it does. In the original issue those methods just returns some awaitable objects that doesn't pass the check. And I fixed it, but only for this certain example (I will add the tests soon). The obstacle is that I don't know if there are similar functions somewhere in the inerpreter. I'm not an internals expert. It would be great if you or someone else could suggest me such places.

[sobolevn]

Please, at least add tests for this feature.

[wrongnull]

as soon as I fully understand the original question

[carljm]

Is there one certain way to define if callable returns awaitable?

See #81371 (comment)

I don't think the current approach in this PR is the right approach; we shouldn't be checking against an approved list of method names.

[carljm]

See above comment.

[wrongnull]

Is there one certain way to define if callable returns awaitable?

See #81371 (comment)

I don't think the current approach in this PR is the right approach; we shouldn't be checking against an approved list of method names.

But there is no way to add attribute to builtin function without monkey patching. Do we need new type(s) to this? Such as builtin_coroutine_function_or_method
Or at least add special flag to already exists ones

[wrongnull]

What if PyCFunctionObject structure contains flags that match co_flags field in code object? Or will they carry the same meaning

[kumaraditya303]

This isn't the way to fix this, I am closing this, please continue the discussion on the issue.