[pathlib] Deprecate additional arguments (#15228)

Author: donbarbos

stdlib/pathlib/__init__.pyi

@@ -104,6 +104,10 @@ class PurePath(PathLike[str]):
     if sys.version_info >= (3, 14):
         def is_relative_to(self, other: StrPath) -> bool: ...
     elif sys.version_info >= (3, 12):
+        @overload
+        def is_relative_to(self, other: StrPath, /) -> bool: ...
+        @overload
+        @deprecated("Passing additional arguments is deprecated since Python 3.12; removed in Python 3.14.")
         def is_relative_to(self, other: StrPath, /, *_deprecated: StrPath) -> bool: ...
     else:
         def is_relative_to(self, *other: StrPath) -> bool: ...
@@ -116,6 +120,10 @@ class PurePath(PathLike[str]):
     if sys.version_info >= (3, 14):
         def relative_to(self, other: StrPath, *, walk_up: bool = False) -> Self: ...
     elif sys.version_info >= (3, 12):
+        @overload
+        def relative_to(self, other: StrPath, /, *, walk_up: bool = False) -> Self: ...
+        @overload
+        @deprecated("Passing additional arguments is deprecated since Python 3.12; removed in Python 3.14.")
         def relative_to(self, other: StrPath, /, *_deprecated: StrPath, walk_up: bool = False) -> Self: ...
     else:
         def relative_to(self, *other: StrPath) -> Self: ...