@overload doesn't work with @asynccontextmanager

Bug Report

When trying to annotate overloads for an asynccontextmanager, I think mypy incorrectly reports an invalid return type.

To Reproduce

from contextlib import asynccontextmanager, contextmanager
from typing import AsyncIterator, Iterator, overload

@overload
@asynccontextmanager
async def test_async() -> AsyncIterator[int]: ...


@overload
@asynccontextmanager
async def test_async(val: int = ...) -> AsyncIterator[int]: ...


@asynccontextmanager
async def test_async(val: int = 1) -> AsyncIterator[int]:
    yield val


@overload
@contextmanager
def test_sync() -> Iterator[int]: ...


@overload
@contextmanager
def test_sync(val: int = ...) -> Iterator[int]: ...


@contextmanager
def test_sync(val: int = 1) -> Iterator[int]:
    yield val

This gives an error of "Argument 1 to "asynccontextmanager" has incompatible type "Callable[[int], Coroutine[Any, Any, AsyncIterator[int]]]"; expected "Callable[[int], AsyncIterator[Never]]"

Where the synchronous version checks fine.

Expected Behavior

I expect the async version to work the same as the sync version

Actual Behavior

Mypy reports and error

mypy test.py
test.py:5: error: Argument 1 to "asynccontextmanager" has incompatible type "Callable[[], Coroutine[Any, Any, AsyncIterator[int]]]"; expected "Callable[[], AsyncIterator[Never]]"  [arg-type]
test.py:10: error: Argument 1 to "asynccontextmanager" has incompatible type "Callable[[int], Coroutine[Any, Any, AsyncIterator[int]]]"; expected "Callable[[int], AsyncIterator[Never]]"  [arg-type]
Found 2 errors in 1 file (checked 1 source file)

Your Environment

• Mypy version used: 1.10.0
• Mypy command-line flags: mypy test.py
• Mypy configuration options from mypy.ini (and other config files):
• Python version used: Python 3.11.4

Führen Sie zunächst die bereitgestellte test.py-Reproduktion mit mypy aus und vergleichen Sie die Fälle asynccontextmanager und contextmanager. Verfolgen Sie die Typprüfung für diese Dekoratoren, fügen Sie dann einen Regressionstest hinzu, der überladene asynccontextmanager-Funktionen abdeckt, und stellen Sie sicher, dass mypy für das korrigierte Verhalten keine Fehler meldet.