Expand protocol allowlist to match CPythons

CHANGELOG.md

@@ -1,5 +1,6 @@
 # Unreleased
 
+- Add support for `AsyncIterator`, `io.Reader`, `io.Writer` and `os.PathLike` protocols.
 - Fix incorrect behaviour on Python 3.9 and Python 3.10 that meant that
   calling `isinstance` with `typing_extensions.Concatenate[...]` or
   `typing_extensions.Unpack[...]` as the first argument could have a different

src/test_typing_extensions.py

@@ -10,6 +10,7 @@
 import inspect
 import io
 import itertools
+import os
 import pickle
 import re
 import subprocess
@@ -3869,9 +3870,15 @@ def test_builtin_protocol_allowlist(self):
             class CustomProtocol(TestCase, Protocol):
                 pass
 
+        class CustomPathLikeProtocol(os.PathLike, Protocol):
+            pass
+
         class CustomContextManager(typing.ContextManager, Protocol):
             pass
 
+        class CustomAsyncIterator(typing.AsyncIterator, Protocol):
+            pass
+
     @skip_if_py312b1
     def test_typing_extensions_protocol_allowlist(self):
         @runtime_checkable
@@ -7064,13 +7071,13 @@ def test_typing_extensions_defers_when_possible(self):
             }
         if sys.version_info < (3, 13):
             exclude |= {
-                'NamedTuple', 'Protocol', 'runtime_checkable', 'Generator',
+                'NamedTuple', 'runtime_checkable', 'Generator',
                 'AsyncGenerator', 'ContextManager', 'AsyncContextManager',
                 'ParamSpec', 'TypeVar', 'TypeVarTuple', 'get_type_hints',
             }
         if sys.version_info < (3, 14):
             exclude |= {
-                'TypeAliasType'
+                'TypeAliasType', 'Protocol'
             }
         if not typing_extensions._PEP_728_IMPLEMENTED:
             exclude |= {'TypedDict', 'is_typeddict'}

src/typing_extensions.py

@@ -614,10 +614,13 @@ def __getitem__(self, params):
 _PROTO_ALLOWLIST = {
     'collections.abc': [
         'Callable', 'Awaitable', 'Iterable', 'Iterator', 'AsyncIterable',
-        'Hashable', 'Sized', 'Container', 'Collection', 'Reversible', 'Buffer',
+        'AsyncIterator', 'Hashable', 'Sized', 'Container', 'Collection',
+        'Reversible', 'Buffer',
     ],
     'contextlib': ['AbstractContextManager', 'AbstractAsyncContextManager'],
+    'io': ['Reader', 'Writer'],
     'typing_extensions': ['Buffer'],
+    'os': ['PathLike'],
 }
 
 
@@ -653,8 +656,10 @@ def _caller(depth=1, default='__main__'):
 
 # `__match_args__` attribute was removed from protocol members in 3.13,
 # we want to backport this change to older Python versions.
-# Breakpoint: https://github.com/python/cpython/pull/110683
-if sys.version_info >= (3, 13):
+# 3.14 additionally added `io.Reader`, `io.Writer` and `os.PathLike` to
+# the list of allowed protocol allowlist.
+# https://github.com/python/cpython/issues/127647
+if sys.version_info >= (3, 14):
     Protocol = typing.Protocol
 else:
     def _allow_reckless_class_checks(depth=2):