https://github.com/python/cpython/commit/71080b8a0fe5da46fb97659060db76fd95a3fb61 commit: 71080b8a0fe5da46fb97659060db76fd95a3fb61 branch: main author: Jelle Zijlstra <[email protected]> committer: JelleZijlstra <[email protected]> date: 2024-05-07T14:16:05Z summary:
gh-118660: Add second type parameter to (Async)ContextManager (#118681) Co-authored-by: Alex Waygood <[email protected]> files: A Misc/NEWS.d/next/Library/2024-05-06-18-13-02.gh-issue-118660.n01Vb7.rst M Doc/library/typing.rst M Lib/test/test_typing.py M Lib/typing.py diff --git a/Doc/library/typing.rst b/Doc/library/typing.rst index 652a3f1f70519c..f53080e0610cb1 100644 --- a/Doc/library/typing.rst +++ b/Doc/library/typing.rst @@ -3819,10 +3819,15 @@ Aliases to other ABCs in :mod:`collections.abc` Aliases to :mod:`contextlib` ABCs """"""""""""""""""""""""""""""""" -.. class:: ContextManager(Generic[T_co]) +.. class:: ContextManager(Generic[T_co, ExitT_co]) Deprecated alias to :class:`contextlib.AbstractContextManager`. + The first type parameter, ``T_co``, represents the type returned by + the :meth:`~object.__enter__` method. The optional second type parameter, ``ExitT_co``, + which defaults to ``bool | None``, represents the type returned by the + :meth:`~object.__exit__` method. + .. versionadded:: 3.5.4 .. deprecated:: 3.9 @@ -3830,10 +3835,18 @@ Aliases to :mod:`contextlib` ABCs now supports subscripting (``[]``). See :pep:`585` and :ref:`types-genericalias`. -.. class:: AsyncContextManager(Generic[T_co]) + .. versionchanged:: 3.13 + Added the optional second type parameter, ``ExitT_co``. + +.. class:: AsyncContextManager(Generic[T_co, AExitT_co]) Deprecated alias to :class:`contextlib.AbstractAsyncContextManager`. + The first type parameter, ``T_co``, represents the type returned by + the :meth:`~object.__aenter__` method. The optional second type parameter, ``AExitT_co``, + which defaults to ``bool | None``, represents the type returned by the + :meth:`~object.__aexit__` method. + .. versionadded:: 3.6.2 .. deprecated:: 3.9 @@ -3841,6 +3854,9 @@ Aliases to :mod:`contextlib` ABCs now supports subscripting (``[]``). See :pep:`585` and :ref:`types-genericalias`. + .. versionchanged:: 3.13 + Added the optional second type parameter, ``AExitT_co``. + Deprecation Timeline of Major Features ====================================== diff --git a/Lib/test/test_typing.py b/Lib/test/test_typing.py index 012613302d1b53..bd116bb1ab7213 100644 --- a/Lib/test/test_typing.py +++ b/Lib/test/test_typing.py @@ -7511,6 +7511,15 @@ def manager(): self.assertIsInstance(cm, typing.ContextManager) self.assertNotIsInstance(42, typing.ContextManager) + def test_contextmanager_type_params(self): + cm1 = typing.ContextManager[int] + self.assertEqual(get_args(cm1), (int, bool | None)) + cm2 = typing.ContextManager[int, None] + self.assertEqual(get_args(cm2), (int, types.NoneType)) + + type gen_cm[T1, T2] = typing.ContextManager[T1, T2] + self.assertEqual(get_args(gen_cm.__value__[int, None]), (int, types.NoneType)) + def test_async_contextmanager(self): class NotACM: pass @@ -7522,11 +7531,17 @@ def manager(): cm = manager() self.assertNotIsInstance(cm, typing.AsyncContextManager) - self.assertEqual(typing.AsyncContextManager[int].__args__, (int,)) + self.assertEqual(typing.AsyncContextManager[int].__args__, (int, bool | None)) with self.assertRaises(TypeError): isinstance(42, typing.AsyncContextManager[int]) with self.assertRaises(TypeError): - typing.AsyncContextManager[int, str] + typing.AsyncContextManager[int, str, float] + + def test_asynccontextmanager_type_params(self): + cm1 = typing.AsyncContextManager[int] + self.assertEqual(get_args(cm1), (int, bool | None)) + cm2 = typing.AsyncContextManager[int, None] + self.assertEqual(get_args(cm2), (int, types.NoneType)) class TypeTests(BaseTestCase): @@ -9953,7 +9968,7 @@ def test_special_attrs(self): typing.ValuesView: 'ValuesView', # Subscribed ABC classes typing.AbstractSet[Any]: 'AbstractSet', - typing.AsyncContextManager[Any]: 'AsyncContextManager', + typing.AsyncContextManager[Any, Any]: 'AsyncContextManager', typing.AsyncGenerator[Any, Any]: 'AsyncGenerator', typing.AsyncIterable[Any]: 'AsyncIterable', typing.AsyncIterator[Any]: 'AsyncIterator', @@ -9963,7 +9978,7 @@ def test_special_attrs(self): typing.ChainMap[Any, Any]: 'ChainMap', typing.Collection[Any]: 'Collection', typing.Container[Any]: 'Container', - typing.ContextManager[Any]: 'ContextManager', + typing.ContextManager[Any, Any]: 'ContextManager', typing.Coroutine[Any, Any, Any]: 'Coroutine', typing.Counter[Any]: 'Counter', typing.DefaultDict[Any, Any]: 'DefaultDict', diff --git a/Lib/typing.py b/Lib/typing.py index e48583673a7be2..8e61f50477bcc2 100644 --- a/Lib/typing.py +++ b/Lib/typing.py @@ -3783,7 +3783,7 @@ def __getattr__(attr): obj = _alias(getattr(re, attr), 1) elif attr in {"ContextManager", "AsyncContextManager"}: import contextlib - obj = _alias(getattr(contextlib, f"Abstract{attr}"), 1, name=attr) + obj = _alias(getattr(contextlib, f"Abstract{attr}"), 2, name=attr, defaults=(bool | None,)) else: raise AttributeError(f"module {__name__!r} has no attribute {attr!r}") globals()[attr] = obj diff --git a/Misc/NEWS.d/next/Library/2024-05-06-18-13-02.gh-issue-118660.n01Vb7.rst b/Misc/NEWS.d/next/Library/2024-05-06-18-13-02.gh-issue-118660.n01Vb7.rst new file mode 100644 index 00000000000000..846a7acb6999b8 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-05-06-18-13-02.gh-issue-118660.n01Vb7.rst @@ -0,0 +1,4 @@ +Add an optional second type parameter to :class:`typing.ContextManager` and +:class:`typing.AsyncContextManager`, representing the return types of +:meth:`~object.__exit__` and :meth:`~object.__aexit__` respectively. +This parameter defaults to ``bool | None``. _______________________________________________ Python-checkins mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3/lists/python-checkins.python.org/ Member address: [email protected]
