No equivalent of inspect.getcoroutinestate for PyAsyncGenASend instances

[GeeTransit]

BPO	37771
Nosy	@agronholm, @1st1, @graingert, @GeeTransit

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2019-08-06.01:20:30.940>
labels = ['type-bug', '3.8', '3.9']
title = 'No equivalent of `inspect.getcoroutinestate` for PyAsyncGenASend instances'
updated_at = <Date 2021-03-06.17:47:09.352>
user = 'https://github.com/GeeTransit'

bugs.python.org fields:

activity = <Date 2021-03-06.17:47:09.352>
actor = 'graingert'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Demos and Tools']
creation = <Date 2019-08-06.01:20:30.940>
creator = 'GeeTransit'
dependencies = []
files = []
hgrepos = []
issue_num = 37771
keywords = []
message_count = 1.0
messages = ['349093']
nosy_count = 4.0
nosy_names = ['alex.gronholm', 'yselivanov', 'graingert', 'GeeTransit']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue37771'
versions = ['Python 3.8', 'Python 3.9']

[GeeTransit]

In PEP-525, async generators were introduced. They use .asend() and .athrow() methods that return a "coroutine-like" object - specifically, a PyAsyncGenASend and PyAsyncGenAThrow respectively.

While these "coroutine-like" object implement .send(), .throw(), and .close(), they don't provide any attributes like normal coroutine objects do such as cr_running or cr_await.

When I use inspect.getcoroutinestate(), it raises an AttributeError on how there isn't a cr_running attribute / flag.

There is a workaround I use which is to wrap it with another coroutine as below:

>>> async def async_generator():
...     yield
...
>>> async def wrap_coro(coro):
...     return await coro
>>> agen = async_generator()
>>> asend = wrap_coro(agen.asend(None))

This seems like something that should be changed to make it more inline with normal coroutines / awaitables.

[iritkatriel]

Duplicate of #79940.

[gschaffner]

i think that this may not be a duplicate of GH-79940. if i understand correctly:

• inspect module does not implement introspection API for asynchronous generators #79940 is about inspecting the state of an async generator object. it was resolved when inspect.getasyncgenstate/inspect.getasyncgenlocals was added.

• this thread is about inspecting the state of an agen.asend(...) "coroutine-like" object (i.e. PyAsyncGenASend, AKA async_generator_asend on CPython). AFAICT it is still not possible to inspect the state of a PyAsyncGenASend unless you wrap it.