Typing-extensions

- Add `typing_extensions.get_protocol_members` and
`typing_extensions.is_protocol` (backport of CPython PR 104878).
Patch by Jelle Zijlstra.
- `typing_extensions` now re-exports all names in the standard library's
`typing` module, except the deprecated `ByteString`. Patch by Jelle
Zijlstra.
- Due to changes in the implementation of `typing_extensions.Protocol`,
`typing.runtime_checkable` can now be used on `typing_extensions.Protocol`
(previously, users had to use `typing_extensions.runtime_checkable` if they
were using `typing_extensions.Protocol`).
- Align the implementation of `TypedDict` with the implementation in the
standard library on Python 3.9 and higher.
`typing_extensions.TypedDict` is now a function instead of a class. The
private functions `_check_fails`, `_dict_new`, and `_typeddict_new`
have been removed. `is_typeddict` now returns `False` when called with
`TypedDict` itself as the argument. Patch by Jelle Zijlstra.
- Declare support for Python 3.12. Patch by Jelle Zijlstra.
- Fix tests on Python 3.13, which removes support for creating
`TypedDict` classes through the keyword-argument syntax. Patch by
Jelle Zijlstra.
- Fix a regression introduced in v4.6.3 that meant that
``issubclass(object, typing_extensions.Protocol)`` would erroneously raise
``TypeError``. Patch by Alex Waygood (backporting the CPython PR
https://github.com/python/cpython/pull/105239).
- Allow `Protocol` classes to inherit from `typing_extensions.Buffer` or
`collections.abc.Buffer`. Patch by Alex Waygood (backporting
https://github.com/python/cpython/pull/104827, by Jelle Zijlstra).
- Allow classes to inherit from both `typing.Protocol` and `typing_extensions.Protocol`
simultaneously. Since v4.6.0, this caused `TypeError` to be raised due to a
metaclass conflict. Patch by Alex Waygood.
- Backport several deprecations from CPython relating to unusual ways to
create `TypedDict`s and `NamedTuple`s. CPython PRs 105609 and 105780
by Alex Waygood; `typing_extensions` backport by Jelle Zijlstra.
- Creating a `NamedTuple` using the functional syntax with keyword arguments
(`NT = NamedTuple("NT", a=int)`) is now deprecated.
- Creating a `NamedTuple` with zero fields using the syntax `NT = NamedTuple("NT")`
or `NT = NamedTuple("NT", None)` is now deprecated.
- Creating a `TypedDict` with zero fields using the syntax `TD = TypedDict("TD")`
or `TD = TypedDict("TD", None)` is now deprecated.
- Fix bug on Python 3.7 where a protocol `X` that had a member `a` would not be
considered an implicit subclass of an unrelated protocol `Y` that only has a
member `a`. Where the members of `X` are a superset of the members of `Y`,
`X` should always be considered a subclass of `Y` iff `Y` is a
runtime-checkable protocol that only has callable members. Patch by Alex
Waygood (backporting CPython PR
https://github.com/python/cpython/pull/105835).

- Fix a regression introduced in v4.6.0 in the implementation of
runtime-checkable protocols. The regression meant
that doing `class Foo(X, typing_extensions.Protocol)`, where `X` was a class that
had `abc.ABCMeta` as its metaclass, would then cause subsequent
`isinstance(1, X)` calls to erroneously raise `TypeError`. Patch by
Alex Waygood (backporting the CPython PR
https://github.com/python/cpython/pull/105152).
- Sync the repository's LICENSE file with that of CPython.
`typing_extensions` is distributed under the same license as
CPython itself.
- Skip a problematic test on Python 3.12.0b1. The test fails on 3.12.0b1 due to
a bug in CPython, which will be fixed in 3.12.0b2. The
`typing_extensions` test suite now passes on 3.12.0b1.

- Fix use of `deprecated` on classes with `__new__` but no `__init__`.
Patch by Jelle Zijlstra.
- Fix regression in version 4.6.1 where comparing a generic class against a
runtime-checkable protocol using `isinstance()` would cause `AttributeError`
to be raised if using Python 3.7.

- Change deprecated `runtime` to formal API `runtime_checkable` in the error
message. Patch by Xuehai Pan.
- Fix regression in 4.6.0 where attempting to define a `Protocol` that was
generic over a `ParamSpec` or a `TypeVarTuple` would cause `TypeError` to be
raised. Patch by Alex Waygood.

- `typing_extensions` is now documented at
https://typing-extensions.readthedocs.io/en/latest/. Patch by Jelle Zijlstra.
- 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 two CPython PRs fixing various issues with `typing.Literal`:
https://github.com/python/cpython/pull/23294 and
https://github.com/python/cpython/pull/23383. Both CPython PRs were
originally by Yurii Karabas, and both were backported to Python >=3.9.1, but
no earlier. Patch by Alex Waygood.

A side effect of one of the changes is that equality comparisons of `Literal`
objects will now raise a `TypeError` if one of the `Literal` objects being
compared has a mutable parameter. (Using mutable parameters with `Literal` is
not supported by PEP 586 or by any major static type checkers.)
- `Literal` is now reimplemented on all Python versions <= 3.10.0. The
`typing_extensions` version does not suffer from the bug that was fixed in
https://github.com/python/cpython/pull/29334. (The CPython bugfix was
backported to CPython 3.10.1 and 3.9.8, but no earlier.)
- Backport [CPython PR 26067](https://github.com/python/cpython/pull/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"](https://docs.python.org/3.12/whatsnew/3.12.html#typing)
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.
- Backport the ability to define `__init__` methods on Protocol classes, a
change made in Python 3.11 (originally implemented in
https://github.com/python/cpython/pull/31628 by Adrian Garcia Badaracco).
Patch by Alex Waygood.
- Speedup `isinstance(3, typing_extensions.SupportsIndex)` by >10x on Python
<3.12. Patch by Alex Waygood.
- Add `typing_extensions` versions of `SupportsInt`, `SupportsFloat`,
`SupportsComplex`, `SupportsBytes`, `SupportsAbs` and `SupportsRound`. These
have the same semantics as the versions from the `typing` module, but
`isinstance()` checks against the `typing_extensions` versions are >10x faster
at runtime on Python <3.12. Patch by Alex Waygood.
- Add `__orig_bases__` to non-generic TypedDicts, call-based TypedDicts, and
call-based NamedTuples. Other TypedDicts and NamedTuples already had the attribute.
Patch by Adrian Garcia Badaracco.
- Add `typing_extensions.get_original_bases`, a backport of
[`types.get_original_bases`](https://docs.python.org/3.12/library/types.html#types.get_original_bases),
introduced in Python 3.12 (CPython PR
https://github.com/python/cpython/pull/101827, originally by James
Hilton-Balfe). Patch by Alex Waygood.

This function should always produce correct results when called on classes
constructed using features from `typing_extensions`. However, it may
produce incorrect results when called on some `NamedTuple` or `TypedDict`
classes that use `typing.{NamedTuple,TypedDict}` on Python <=3.11.
- Constructing a call-based `TypedDict` using keyword arguments for the fields
now causes a `DeprecationWarning` to be emitted. This matches the behaviour
of `typing.TypedDict` on 3.11 and 3.12.
- Backport the implementation of `NewType` from 3.10 (where it is implemented
as a class rather than a function). This allows user-defined `NewType`s to be
pickled. Patch by Alex Waygood.
- Fix tests and import on Python 3.12, where `typing.TypeVar` can no longer be
subclassed. Patch by Jelle Zijlstra.
- Add `typing_extensions.TypeAliasType`, a backport of `typing.TypeAliasType`
from PEP 695. Patch by Jelle Zijlstra.
- Backport changes to the repr of `typing.Unpack` that were made in order to
implement [PEP 692](https://peps.python.org/pep-0692/) (backport of
https://github.com/python/cpython/pull/104048). Patch by Alex Waygood.

- Runtime support for PEP 702, adding `typing_extensions.deprecated`. Patch
by Jelle Zijlstra.
- Add better default value for TypeVar `default` parameter, PEP 696. Enables
runtime check if `None` was passed as default. Patch by Marc Mueller (cdce8p).
- The `typing_extensions.override` decorator now sets the `.__override__`
attribute. Patch by Steven Troxler.
- Fix `get_type_hints()` on cross-module inherited `TypedDict` in 3.9 and 3.10.
Patch by Carl Meyer.
- Add `frozen_default` parameter on `dataclass_transform`. Patch by Erik De Bonte.