Add Status protocol.

Lib/pathlib/_types.py

@@ -20,3 +20,13 @@ def splitdrive(self, path: str) -> tuple[str, str]: ...
     def splitext(self, path: str) -> tuple[str, str]: ...
     def normcase(self, path: str) -> str: ...
     def isabs(self, path: str) -> bool: ...
+
+
+@runtime_checkable
+class Status(Protocol):
+    """Protocol for path statuses, which support querying the file type.
+    Methods may return cached results.
+    """
+    def is_dir(self, *, follow_symlinks: bool = True) -> bool: ...
+    def is_file(self, *, follow_symlinks: bool = True) -> bool: ...
+    def is_symlink(self) -> bool: ...

Lib/test/test_pathlib/test_pathlib_abc.py

@@ -6,7 +6,7 @@
 import unittest
 
 from pathlib._abc import UnsupportedOperation, PurePathBase, PathBase
-from pathlib._types import Parser
+from pathlib._types import Parser, Status
 import posixpath
 
 from test.support.os_helper import TESTFN
@@ -1902,7 +1902,7 @@ def test_iterdir_status(self):
         p = self.cls(self.base)
         for child in p.iterdir():
             entry = child._status
-            self.assertIsNotNone(entry)
+            self.assertIsInstance(entry, Status)
             self.assertEqual(entry.is_dir(follow_symlinks=False),
                              child.is_dir(follow_symlinks=False))
             self.assertEqual(entry.is_file(follow_symlinks=False),