Fix moving a file/directory to itself.

Doc/library/pathlib.rst

@@ -1598,8 +1598,9 @@ Copying, moving and deleting
    return a new :class:`!Path` instance pointing to *target*.
 
    If the *target* doesn't exist it will be created. If both this path and the
-   *target* are existing files, then the target is overwritten. If the
-   *target* is a non-empty directory, :exc:`OSError` is raised.
+   *target* are existing files, then the target is overwritten. If both paths
+   point to the same file or directory, or the *target* is a non-empty
+   directory, then :exc:`OSError` is raised.
 
    If both paths are on the same filesystem, the move is performed with
    :func:`os.replace`. Otherwise, this path is copied (preserving metadata and

Lib/pathlib/_local.py

@@ -854,7 +854,8 @@ def move(self, target):
         """
         Recursively move this file or directory tree to the given destination.
         """
-
+        if self._samefile_safe(target):
+            raise OSError(f"{self!r} and {target!r} are the same file")
         try:
             return self.replace(target)
         except TypeError:

Lib/test/test_pathlib/test_pathlib_abc.py

@@ -2011,6 +2011,11 @@ def test_move_file_to_dir(self):
         target = base / 'dirB'
         self.assertRaises(OSError, source.move, target)
 
+    def test_move_file_to_itself(self):
+        base = self.cls(self.base)
+        source = base / 'fileA'
+        self.assertRaises(OSError, source.move, source)
+
     def test_move_dir(self):
         base = self.cls(self.base)
         source = base / 'dirC'
@@ -2033,6 +2038,11 @@ def test_move_dir_to_dir(self):
         target = base / 'dirB'
         self.assertRaises(OSError, source.move, target)
 
+    def test_move_dir_to_itself(self):
+        base = self.cls(self.base)
+        source = base / 'dirC'
+        self.assertRaises(OSError, source.move, source)
+
     def test_move_dir_into_itself(self):
         base = self.cls(self.base)
         source = base / 'dirC'