When I annotate an async function with @deprecated(...), inspect.iscoroutinefunction no longer returns True. This is not what I expect to happen, as with partial from functools this does not happen.

Consider the following code:

import inspect

from functools import partial
from typing_extensions import deprecated


async def coroutinefunction_a():
    pass


@deprecated("deprecated coroutine")
async def coroutinefunction_b():
    pass


assert inspect.iscoroutinefunction(coroutinefunction_a) is True  # correct
assert inspect.iscoroutinefunction(partial(coroutinefunction_a)) is True  # correct
assert inspect.iscoroutinefunction(coroutinefunction_b) is True  # fail

With typing_extensions and python3.13, the last assertion fails.

This is especially annoying since e.g. libraries use inspect.iscoroutinefunction to detect the type of function.

I am not sure this is the correct place for this bug report, as this both happens with python 3.13 and typing_extensions on older python versions.

Linked PRs

• gh-122088: Copy the coroutine status of the underlying callable in @warnings.deprecated #122086
• [3.13] gh-122088: Copy the coroutine status of the underlying callable in @warnings.deprecated (GH-122086) #122156