Add get_origin annotations (#9811)

Co-authored-by: Alex Waygood <[email protected]>

Author: zmievsa

stdlib/typing.pyi

@@ -20,6 +20,11 @@ from types import (
 )
 from typing_extensions import Never as _Never, ParamSpec as _ParamSpec, final as _final
 
+if sys.version_info >= (3, 10):
+    from types import UnionType
+if sys.version_info >= (3, 9):
+    from types import GenericAlias
+
 __all__ = [
     "AbstractSet",
     "Any",
@@ -745,9 +750,21 @@ else:
     ) -> dict[str, Any]: ...
 
 if sys.version_info >= (3, 8):
-    def get_origin(tp: Any) -> Any | None: ...
     def get_args(tp: Any) -> tuple[Any, ...]: ...
 
+    if sys.version_info >= (3, 10):
+        @overload
+        def get_origin(tp: ParamSpecArgs | ParamSpecKwargs) -> ParamSpec: ...
+        @overload
+        def get_origin(tp: UnionType) -> type[UnionType]: ...
+    if sys.version_info >= (3, 9):
+        @overload
+        def get_origin(tp: GenericAlias) -> type: ...
+        @overload
+        def get_origin(tp: Any) -> Any | None: ...
+    else:
+        def get_origin(tp: Any) -> Any | None: ...
+
 @overload
 def cast(typ: Type[_T], val: Any) -> _T: ...
 @overload

stdlib/typing_extensions.pyi

@@ -32,6 +32,11 @@ from typing import (  # noqa: Y022,Y039
     type_check_only,
 )
 
+if sys.version_info >= (3, 10):
+    from types import UnionType
+if sys.version_info >= (3, 9):
+    from types import GenericAlias
+
 __all__ = [
     "Any",
     "ClassVar",
@@ -155,6 +160,18 @@ def get_type_hints(
     include_extras: bool = False,
 ) -> dict[str, Any]: ...
 def get_args(tp: Any) -> tuple[Any, ...]: ...
+
+if sys.version_info >= (3, 10):
+    @overload
+    def get_origin(tp: UnionType) -> type[UnionType]: ...
+
+if sys.version_info >= (3, 9):
+    @overload
+    def get_origin(tp: GenericAlias) -> type: ...
+
+@overload
+def get_origin(tp: ParamSpecArgs | ParamSpecKwargs) -> ParamSpec: ...
+@overload
 def get_origin(tp: Any) -> Any | None: ...
 
 Annotated: _SpecialForm