gh-101360: Fix anchor matching in pathlib.PureWindowsPath.match() (GH-101363)

Use `fnmatch` to match path and pattern anchors, just as we do for other
path parts. This allows patterns such as `'*:/Users/*'` to be matched.

Author: barneygale

Lib/pathlib.py

@@ -647,15 +647,10 @@ def match(self, path_pattern):
         drv, root, pat_parts = self._parse_parts((path_pattern,))
         if not pat_parts:
             raise ValueError("empty pattern")
-        elif drv and drv != self._flavour.normcase(self._drv):
-            return False
-        elif root and root != self._root:
-            return False
         parts = self._parts_normcase
         if drv or root:
             if len(pat_parts) != len(parts):
                 return False
-            pat_parts = pat_parts[1:]
         elif len(pat_parts) > len(parts):
             return False
         for part, pat in zip(reversed(parts), reversed(pat_parts)):

Lib/test/test_ntpath.py

@@ -200,6 +200,10 @@ def test_splitroot(self):
         tester('ntpath.splitroot("//x")', ("//x", "", ""))  # non-empty server & missing share
         tester('ntpath.splitroot("//x/")', ("//x/", "", ""))  # non-empty server & empty share
 
+        # gh-101363: match GetFullPathNameW() drive letter parsing behaviour
+        tester('ntpath.splitroot(" :/foo")', (" :", "/", "foo"))
+        tester('ntpath.splitroot("/:/foo")', ("", "/", ":/foo"))
+
     def test_split(self):
         tester('ntpath.split("c:\\foo\\bar")', ('c:\\foo', 'bar'))
         tester('ntpath.split("\\\\conky\\mountpoint\\foo\\bar")',

Lib/test/test_pathlib.py

@@ -852,8 +852,7 @@ def test_as_uri(self):
     def test_match_common(self):
         P = self.cls
         # Absolute patterns.
-        self.assertTrue(P('c:/b.py').match('/*.py'))
-        self.assertTrue(P('c:/b.py').match('c:*.py'))
+        self.assertTrue(P('c:/b.py').match('*:/*.py'))
         self.assertTrue(P('c:/b.py').match('c:/*.py'))
         self.assertFalse(P('d:/b.py').match('c:/*.py'))  # wrong drive
         self.assertFalse(P('b.py').match('/*.py'))
@@ -864,14 +863,18 @@ def test_match_common(self):
         self.assertFalse(P('/b.py').match('c:*.py'))
         self.assertFalse(P('/b.py').match('c:/*.py'))
         # UNC patterns.
-        self.assertTrue(P('//some/share/a.py').match('/*.py'))
+        self.assertTrue(P('//some/share/a.py').match('//*/*/*.py'))
         self.assertTrue(P('//some/share/a.py').match('//some/share/*.py'))
         self.assertFalse(P('//other/share/a.py').match('//some/share/*.py'))
         self.assertFalse(P('//some/share/a/b.py').match('//some/share/*.py'))
         # Case-insensitivity.
         self.assertTrue(P('B.py').match('b.PY'))
         self.assertTrue(P('c:/a/B.Py').match('C:/A/*.pY'))
         self.assertTrue(P('//Some/Share/B.Py').match('//somE/sharE/*.pY'))
+        # Path anchor doesn't match pattern anchor
+        self.assertFalse(P('c:/b.py').match('/*.py'))  # 'c:/' vs '/'
+        self.assertFalse(P('c:/b.py').match('c:*.py'))  # 'c:/' vs 'c:'
+        self.assertFalse(P('//some/share/a.py').match('/*.py'))  # '//some/share/' vs '/'
 
     def test_ordering_common(self):
         # Case-insensitivity.

Misc/NEWS.d/next/Library/2023-01-27-02-53-50.gh-issue-101360.bPB7SL.rst

@@ -0,0 +1,3 @@
+Fix anchor matching in :meth:`pathlib.PureWindowsPath.match`. Path and
+pattern anchors are now matched with :mod:`fnmatch`, just like other path
+parts. This allows patterns such as ``"*:/Users/*"`` to be matched.