Issue 32526: Closing async generator while it is running does not raise an exception (original) (raw)

It looks like Python's tracking the "running" state of async generators wrong: we should have ag_running set to True when we enter asend/athrow/aclose and False when we exit, but instead it's being toggled back and forth on each inner send/throw on the individual coroutines.

Here's a minimal reproducer (using some random recent checkout of master):

async def f(): ... await asyncio.sleep(1) ... yield ... ag = f() asend_coro = ag.asend(None) fut = asend_coro.send(None)

Logically, ag.asend is still running, waiting for that sleep to

finish, but we have lost track:

ag.ag_running False

We can start another call to asend() going simultaneously

fut.set_result(None) send_coro2 = ag.asend(None) send_coro2.send(None) Traceback (most recent call last): File "", line 1, in StopIteration

It looks like async_generator did handle this case correctly, but didn't have a test case. I just added one: https://github.com/njsmith/async_generator/commit/339fc6309aa6c96244e79b517db0b98ba0ccfb2a