fix for os.path.splitroot on 3.13

stdlib/@tests/stubtest_allowlists/darwin-py313.txt

@@ -1,6 +1,4 @@
 # new in py313
-posixpath.splitroot
-
 # Depends on HAVE_NCURSESW and how we install CPython,
 # should be removed when 3.13 will be officially released:
 _?curses.unget_wch

stdlib/@tests/stubtest_allowlists/linux-py313.txt

@@ -1,2 +0,0 @@
-# TODO: triage these (new in py313)
-posixpath.splitroot

stdlib/@tests/stubtest_allowlists/py313.txt

@@ -4,7 +4,6 @@
 
 # TODO: triage these new errors
 _tkinter.create
-os.path.splitroot
 tkinter.Misc.after_info
 tkinter.Misc.busy
 tkinter.Misc.busy_cget

stdlib/ntpath.pyi

@@ -1,5 +1,5 @@
 import sys
-from _typeshed import BytesPath, StrOrBytesPath, StrPath
+from _typeshed import AnyOrLiteralStr, BytesPath, StrOrBytesPath, StrPath
 from genericpath import (
     commonprefix as commonprefix,
     exists as exists,
@@ -46,7 +46,7 @@ from typing import AnyStr, overload
 from typing_extensions import LiteralString
 
 if sys.version_info >= (3, 12):
-    from posixpath import isjunction as isjunction, splitroot as splitroot
+    from posixpath import isjunction as isjunction
 if sys.version_info >= (3, 13):
     from genericpath import isdevdrive as isdevdrive
 
@@ -124,3 +124,9 @@ else:
 
 if sys.version_info >= (3, 13):
     def isreserved(path: StrOrBytesPath) -> bool: ...
+
+if sys.version_info >= (3, 12):
+    @overload
+    def splitroot(p: AnyOrLiteralStr) -> tuple[AnyOrLiteralStr, AnyOrLiteralStr, AnyOrLiteralStr]: ...
+    @overload
+    def splitroot(p: PathLike[AnyStr]) -> tuple[AnyStr, AnyStr, AnyStr]: ...

stdlib/posixpath.pyi

@@ -160,6 +160,14 @@ def lexists(path: FileDescriptorOrPath) -> bool: ...
 
 if sys.version_info >= (3, 12):
     def isjunction(path: StrOrBytesPath) -> bool: ...
+
+if sys.version_info >= (3, 13) and sys.platform != "win32":
+    @overload
+    def splitroot(path: AnyOrLiteralStr) -> tuple[AnyOrLiteralStr, AnyOrLiteralStr, AnyOrLiteralStr]: ...
+    @overload
+    def splitroot(path: PathLike[AnyStr]) -> tuple[AnyStr, AnyStr, AnyStr]: ...
+
+elif sys.version_info >= (3, 12):
     @overload
     def splitroot(p: AnyOrLiteralStr) -> tuple[AnyOrLiteralStr, AnyOrLiteralStr, AnyOrLiteralStr]: ...
     @overload