Typing-extensions

- Add `typing_extensions.Doc`, as proposed by PEP 727. Patch by
Sebastián Ramírez.
- Drop support for Python 3.7 (including PyPy-3.7). Patch by Alex Waygood.
- Fix bug where `get_original_bases()` would return incorrect results when
called on a concrete subclass of a generic class. Patch by Alex Waygood
(backporting https://github.com/python/cpython/pull/107584, by James
Hilton-Balfe).
- Fix bug where `ParamSpec(default=...)` would raise a `TypeError` on Python
versions <3.11. Patch by James Hilton-Balfe

- Fix support for `TypedDict`, `NamedTuple` and `is_protocol` on PyPy-3.7 and
PyPy-3.8. Patch by Alex Waygood. Note that PyPy-3.7 and PyPy-3.8 are unsupported
by the PyPy project. The next feature release of typing-extensions will
drop support for PyPy-3.7 and may also drop support for PyPy-3.8.

- This is expected to be the last feature release supporting Python 3.7,
which reaches its end of life on June 27, 2023. Version 4.8.0 will support
only Python 3.8.0 and up.
- Fix bug where a `typing_extensions.Protocol` class that had one or more
non-callable members would raise `TypeError` when `issubclass()`
was called against it, even if it defined a custom `__subclasshook__`
method. The correct behaviour -- which has now been restored -- is not to
raise `TypeError` in these situations if a custom `__subclasshook__` method
is defined. Patch by Alex Waygood (backporting
https://github.com/python/cpython/pull/105976).

- 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.