Add typing_extensions.Buffer, a marker class for buffer types, as proposed by PEP 688. Equivalent to collections.abc.Buffer in Python 3.12. Patch by Jelle Zijlstra.
Backport CPython PR 26067 (originally by Yurii Karabas), ensuring that isinstance() calls on protocols raise TypeError when the protocol is not decorated with @runtime_checkable. Patch by Alex Waygood.
Backport several significant performance improvements to runtime-checkable protocols that have been made in Python 3.12 (see https://github.com/python/cpython/issues/74690 for details). Patch by Alex Waygood.
A side effect of one of the performance improvements is that the members of a runtime-checkable protocol are now considered “frozen” at runtime as soon as the class has been created. Monkey-patching attributes onto a runtime-checkable protocol will still work, but will have no impact on isinstance() checks comparing objects to the protocol. See “What's New in Python 3.12” for more details.
isinstance() checks against runtime-checkable protocols now use inspect.getattr_static() rather than hasattr() to lookup whether attributes exist (backporting https://github.com/python/cpython/pull/103034). This means that descriptors and __getattr__ methods are no longer unexpectedly evaluated during isinstance() checks against runtime-checkable protocols. However, it may also mean that some objects which used to be considered instances of a runtime-checkable protocol on older versions of typing_extensions may no longer be considered instances of that protocol using the new release, and vice versa. Most users are unlikely to be affected by this change. Patch by Alex Waygood.
typing_extensions.deprecated. Patch by Jelle Zijlstra.default parameter, PEP 696. Enables runtime check if None was passed as default. Patch by Marc Mueller (@cdce8p).@typing_extensions.override decorator now sets the .__override__ attribute. Patch by Steven Troxler.get_type_hints() on cross-module inherited TypedDict in 3.9 and 3.10. Patch by Carl Meyer.frozen_default parameter on dataclass_transform. Patch by Erik De Bonte.typing_extensions.Any a backport of python 3.11's Any class which is subclassable at runtime. (backport from python/cpython#31841, by Shantanu and Jelle Zijlstra). Patch by James Hilton-Balfe (@Gobot1234).default parameter, PEP 696. Patch by Marc Mueller (@cdce8p).typing_extensions.override. Patch by Jelle Zijlstra.infer_variance parameter to TypeVar, as specified in PEP 695. Patch by Jelle Zijlstra.typing_extensions.NamedTuple, allowing for generic NamedTuples on Python <3.11 (backport from python/cpython#92027, by Serhiy Storchaka). Patch by Alex Waygood (@AlexWaygood).typing_extensions.TypedDict to allow for generic TypedDicts on Python <3.11 (backport from python/cpython#27663, by Samodya Abey). Patch by Alex Waygood (@AlexWaygood).typing.Unpack and typing.TypeVarTuple on Python 3.11.ParamSpecArgs and ParamSpecKwargs to __all__.typing_extensions.dataclass_transform to rename the field_descriptors parameter to field_specifiers and accept arbitrary keyword arguments.typing_extensions.get_overloads and typing_extensions.clear_overloads, and add registry support to typing_extensions.overload. Backport from python/cpython#89263.typing_extensions.assert_type. Backport from bpo-46480.typing_extensions on Python 3.7.0 and 3.7.1. Original patch by Nikita Sobolev (@sobolevn).typing_extensions.TypeVarTuple and typing_extensions.Unpack.Required and NotRequired with __required_keys__, __optional_keys__ and get_type_hints(). Patch by David Cabot (@d-k-bo).typing_extensions.LiteralString.Never and assert_never. Backport from bpo-46475.ParamSpec args and kwargs are now equal to themselves. Backport from bpo-46676. Patch by Gregory Beauregard (@GBeauregard).reveal_type. Backport from bpo-46414.typing_extensions.dataclass_transform.Annotated can now wrap ClassVar and Final. Backport from bpo-46491. Patch by Gregory Beauregard (@GBeauregard).Required and NotRequired to __all__. Patch by Yuri Karabas (@uriyyo).@final decorator now sets the __final__ attribute on the decorated object to allow runtime introspection. Backport from bpo-46342.is_typeddict. Patch by Chris Moradi (@chrismoradi) and James Hilton-Balfe (@Gobot1234).Required and NotRequired. Patch by Jelle Zijlstra (@jellezijlstra).Self as a type argument. Patch by Chris Wesseling (@CharString) and James Hilton-Balfe (@Gobot1234).typing_extensions.Self. Patch by James Hilton-Balfe (@Gobot1234).typing_extensions.Required and NotRequired. Patch by David Foster (@davidfstr).The following non-exported but non-private names have been removed as they are unneeded for supporting Python 3.6 and newer.
Prior to release 4.0.0 we did not provide a changelog. Please check the Git history for details.