Remove typing.AwaitableGenerator #13804

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1. brianschubert commented on Apr 7, 2025

   

   brianschubert

   on Apr 7, 2025

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   I don't know the background, but mypy makes use of this, e.g. here https://github.com/python/mypy/blob/749f2584da9425173d68eb220db7e92aa13ad8ea/mypy/checkexpr.py#L6361-L6382

   So I would say it's intentional :)
2. srittau commented on Apr 7, 2025

   

   srittau

   on Apr 7, 2025

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   AwaitableGenerator should probably not exist in typeshed. It's a holdover from when mypy and typeshed were tightly coupled. Cf. python/mypy#8699 and python/mypy#8240.

   👍React with 👍3Reacted by Brian Schubert, Jelle Zijlstra and Alan Bogarin
3. srittau

   changed the title [-]Unused type variable in AwaitableGenerator[/-] [+]Remove typing.AwaitableGenerator[/+] on Apr 7, 2025
4. srittau

   added

   status: deferredIssue or PR deferred until some precondition is fixedIssue or PR deferred until some precondition is fixed

   on Apr 7, 2025
5. AlanBogarin commented on Apr 9, 2025

   

   AlanBogarin

   on Apr 9, 2025

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   I have a proposal for typing generator-based coroutines.

   When using yield from with a types.CoroutineType, replace AwaitableGenerator with Generator.

   This is consistent with its runtime type types.GeneratorType, prevents using await if it is not decorated with @types.coroutine, and Generator has existed since v3.5.

   Some drawbacks:
   Extending linters’ functionality to determine the types involved in a coroutine for yield from.

   from __future__ import annotations
   
   import types
   import asyncio
   
   from collections.abc import Generator
   from typing import Any
   
   @types.coroutine
   def generator_a(): # () -> Generator[None, Any, None]
       yield None
   
   # @types.coroutine
   def generator_b() -> Generator[Any, Any, None]:
       yield from asyncio.sleep(1)  # type: ignore[misc]
   
   # () -> AwaitableGenerator[Any, Any, None, Any]
   def generator_c():
       yield from asyncio.sleep(1)
   
   async def test_awaitable() -> None:
       await generator_a() # ok
       await generator_b()  # TypeError! without @coroutine
       await generator_c() # bad: no @coroutine mark

   Taking advantage of the topic: inspect can detect these objects marked with @types.coroutine via inspect.isawaitable, but it lacks an introspection function specifically for them.

   def isgeneratorcoroutine(o: object) -> typing.TypeGuard[types.GeneratorType[Any, Any, Any]]:
       return inspect.isgenerator(o) and bool(o.gi_code.co_flags & inspect.CO_ITERABLE_COROUTINE)
6. srittau

   closed this as a duplicateof Remove type checker-specific symbols from builtins.pyi and typing.pyi #7580 on Apr 11, 2025