Update typing_extensions to >=4.16.0rc2 (#15946)

* Update typing_extensions.TypeVarTuple with new backported features

* Update typing_extensions to 4.16.0rc2

---------

Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

Author: carljm

requirements-tests.txt

@@ -17,7 +17,7 @@ stubdefaulter==0.1.0; python_version < "3.15"
 termcolor>=2.3
 tomli==2.4.1; python_version < "3.11"
 tomlkit==0.14.0
-typing_extensions>=4.16.0rc1
+typing_extensions>=4.16.0rc2
 uv==0.11.15
 
 # Utilities for typeshed infrastructure scripts.

stdlib/@tests/stubtest_allowlists/py313.txt

@@ -66,6 +66,11 @@ tkinter.simpledialog.TkVersion
 # that describes the way users are supposed to call the constructor.
 typing_extensions.sentinel.__init__
 
+# TypeVarTuple is a wrapper class that returns typing.TypeVarTuple instances.
+# Keep __new__ checked because it is the wrapper's public constructor.
+typing_extensions\.TypeVarTuple
+typing_extensions\.TypeVarTuple\.(?!__new__).*
+
 
 # =============================================================
 # Allowlist entries that cannot or should not be fixed; <3.15

stdlib/@tests/stubtest_allowlists/py314.txt

@@ -66,6 +66,11 @@ tkinter.simpledialog.TkVersion
 # that describes the way users are supposed to call the constructor.
 typing_extensions.sentinel.__init__
 
+# TypeVarTuple is a wrapper class that returns typing.TypeVarTuple instances.
+# Keep __new__ checked because it is the wrapper's public constructor.
+typing_extensions\.TypeVarTuple
+typing_extensions\.TypeVarTuple\.(?!__new__).*
+
 
 # =============================================================
 # Allowlist entries that cannot or should not be fixed; <3.15

stdlib/typing_extensions.pyi

@@ -71,6 +71,9 @@ from typing import (  # noqa: Y022,Y037,Y038,Y039,UP035
     type_check_only,
 )
 
+if sys.version_info >= (3, 14):
+    from _typeshed import EvaluateFunc
+
 # Please keep order the same as at runtime.
 __all__ = [
     # Super-special typing primitives.
@@ -458,7 +461,6 @@ if sys.version_info >= (3, 13):
         ReadOnly as ReadOnly,
         TypeIs as TypeIs,
         TypeVar as TypeVar,
-        TypeVarTuple as TypeVarTuple,
         get_protocol_members as get_protocol_members,
         is_protocol as is_protocol,
     )
@@ -547,19 +549,58 @@ else:
         def has_default(self) -> bool: ...
         def __typing_prepare_subst__(self, alias: Any, args: Any) -> tuple[Any, ...]: ...
 
+    ReadOnly: _SpecialForm
+    TypeIs: _SpecialForm
+
+if sys.version_info >= (3, 15):
+    from typing import TypeVarTuple as TypeVarTuple
+else:
     @final
     class TypeVarTuple:
         @property
         def __name__(self) -> str: ...
         @property
+        def __bound__(self) -> AnnotationForm | None: ...
+        @property
+        def __covariant__(self) -> bool: ...
+        @property
+        def __contravariant__(self) -> bool: ...
+        @property
+        def __infer_variance__(self) -> bool: ...
+        @property
         def __default__(self) -> AnnotationForm: ...
-        def __init__(self, name: str, *, default: AnnotationForm = ...) -> None: ...
+        if sys.version_info >= (3, 11):
+            def __new__(
+                cls,
+                name: str,
+                *,
+                bound: AnnotationForm | None = None,
+                covariant: bool = False,
+                contravariant: bool = False,
+                infer_variance: bool = False,
+                default: AnnotationForm = ...,
+            ) -> Self: ...
+        else:
+            def __init__(
+                self,
+                name: str,
+                *,
+                bound: AnnotationForm | None = None,
+                covariant: bool = False,
+                contravariant: bool = False,
+                infer_variance: bool = False,
+                default: AnnotationForm = ...,
+            ) -> None: ...
+
         def __iter__(self) -> Any: ...  # Unpack[Self]
         def has_default(self) -> bool: ...
-        def __typing_prepare_subst__(self, alias: Any, args: Any) -> tuple[Any, ...]: ...
+        if sys.version_info >= (3, 11):
+            def __typing_subst__(self, arg: Never, /) -> Never: ...
 
-    ReadOnly: _SpecialForm
-    TypeIs: _SpecialForm
+        def __typing_prepare_subst__(self, alias: Any, args: Any, /) -> tuple[Any, ...]: ...
+        if sys.version_info >= (3, 14):
+            @property
+            def evaluate_default(self) -> EvaluateFunc | None: ...
 
 # TypeAliasType was added in Python 3.12, but had significant changes in 3.14.
 if sys.version_info >= (3, 14):