GH-127381: pathlib ABCs: remove case_sensitive argument (#131024)

Remove the *case_sensitive* argument from `_JoinablePath.full_match()` and
`_ReadablePath.glob()`. Using a non-native case sensitivity forces the use
of "case-pedantic" globbing, where we `iterdir()` even for non-wildcard
pattern segments. But it's hard to know when to enable this mode, as
case-sensitivity can vary by directory, so `_PathParser.normcase()` doesn't
always give the full picture. The `Path.glob()` implementation is forced to
make an educated guess, but we can avoid the issue in the ABCs by dropping
the *case_sensitive* argument.

(I probably shouldn't have added these arguments in `PurePath` and `Path`
in the first place!)

Also drop support for `_ReadablePath.glob(recurse_symlinks=False)`, which
makes recursive globbing much slower.

Lib/pathlib/types.py

@@ -11,7 +11,7 @@ Protocols for supporting classes in pathlib.
 
 
 from abc import ABC, abstractmethod
-from glob import _PathGlobber, _no_recurse_symlinks
+from glob import _PathGlobber
 from pathlib import PurePath, Path
 from pathlib._os import magic_open, ensure_distinct_paths, copy_file
 from typing import Optional, Protocol, runtime_checkable
@@ -216,14 +216,13 @@ class _JoinablePath(ABC):
             parent = split(path)[0]
         return tuple(parents)
 
-    def full_match(self, pattern, *, case_sensitive=None):
+    def full_match(self, pattern):
         """
         Return True if this path matches the given glob-style pattern. The
         pattern is matched against the entire path.
         """
         if not hasattr(pattern, 'with_segments'):
             pattern = self.with_segments(pattern)
-        if case_sensitive is None:
         case_sensitive = self.parser.normcase('Aa') == 'Aa'
         globber = _PathGlobber(pattern.parser.sep, case_sensitive, recursive=True)
         match = globber.compile(str(pattern), altsep=pattern.parser.altsep)
@@ -279,7 +278,7 @@ class _ReadablePath(_JoinablePath):
         """
         raise NotImplementedError
 
-    def glob(self, pattern, *, case_sensitive=None, recurse_symlinks=True):
+    def glob(self, pattern, *, recurse_symlinks=True):
         """Iterate over this subtree and yield all existing files (of any
         kind, including directories) matching the given relative pattern.
         """
@@ -288,14 +287,10 @@ class _ReadablePath(_JoinablePath):
         anchor, parts = _explode_path(pattern)
         if anchor:
             raise NotImplementedError("Non-relative patterns are unsupported")
-        case_sensitive_default = self.parser.normcase('Aa') == 'Aa'
+        elif not recurse_symlinks:
-        if case_sensitive is None:
+            raise NotImplementedError("recurse_symlinks=False is unsupported")
-            case_sensitive = case_sensitive_default
+        case_sensitive = self.parser.normcase('Aa') == 'Aa'
-            case_pedantic = False
+        globber = _PathGlobber(self.parser.sep, case_sensitive, recursive=True)
-        else:
-            case_pedantic = case_sensitive_default != case_sensitive
-        recursive = True if recurse_symlinks else _no_recurse_symlinks
-        globber = _PathGlobber(self.parser.sep, case_sensitive, case_pedantic, recursive)
         select = globber.selector(parts)
         return select(self.joinpath(''))
 

Lib/test/test_pathlib/test_join.py

@@ -130,11 +130,6 @@ class JoinTestBase:
         self.assertFalse(P('a/b/c.py').full_match('**/a/b/c./**'))
         self.assertFalse(P('a/b/c.py').full_match('/a/b/c.py/**'))
         self.assertFalse(P('a/b/c.py').full_match('/**/a/b/c.py'))
-        # Case-sensitive flag
-        self.assertFalse(P('A.py').full_match('a.PY', case_sensitive=True))
-        self.assertTrue(P('A.py').full_match('a.PY', case_sensitive=False))
-        self.assertFalse(P('c:/a/B.Py').full_match('C:/A/*.pY', case_sensitive=True))
-        self.assertTrue(P('/a/b/c.py').full_match('/A/*/*.Py', case_sensitive=False))
         # Matching against empty path
         self.assertFalse(P('').full_match('*'))
         self.assertTrue(P('').full_match('**'))

Lib/test/test_pathlib/test_pathlib.py

@@ -433,6 +433,13 @@ class PurePathTest(test_pathlib_abc.JoinablePathTest):
         with self.assertWarns(DeprecationWarning):
             p.is_reserved()
 
+    def test_full_match_case_sensitive(self):
+        P = self.cls
+        self.assertFalse(P('A.py').full_match('a.PY', case_sensitive=True))
+        self.assertTrue(P('A.py').full_match('a.PY', case_sensitive=False))
+        self.assertFalse(P('c:/a/B.Py').full_match('C:/A/*.pY', case_sensitive=True))
+        self.assertTrue(P('/a/b/c.py').full_match('/A/*/*.Py', case_sensitive=False))
+
     def test_match_empty(self):
         P = self.cls
         self.assertRaises(ValueError, P('a').match, '')
@@ -2737,6 +2744,18 @@ class PathTest(test_pathlib_abc.RWPathTest, PurePathTest):
         self.assertEqual(expect, set(p.glob(P(pattern))))
         self.assertEqual(expect, set(p.glob(FakePath(pattern))))
 
+    def test_glob_case_sensitive(self):
+        P = self.cls
+        def _check(path, pattern, case_sensitive, expected):
+            actual = {str(q) for q in path.glob(pattern, case_sensitive=case_sensitive)}
+            expected = {str(P(self.base, q)) for q in expected}
+            self.assertEqual(actual, expected)
+        path = P(self.base)
+        _check(path, "DIRB/FILE*", True, [])
+        _check(path, "DIRB/FILE*", False, ["dirB/fileB"])
+        _check(path, "dirb/file*", True, [])
+        _check(path, "dirb/file*", False, ["dirB/fileB"])
+
     @needs_symlinks
     def test_glob_dot(self):
         P = self.cls

Lib/test/test_pathlib/test_pathlib_abc.py

@@ -709,18 +709,6 @@ class ReadablePathTest(JoinablePathTest):
         p = P(self.base)
         self.assertEqual(list(p.glob("")), [p.joinpath("")])
 
-    def test_glob_case_sensitive(self):
-        P = self.cls
-        def _check(path, pattern, case_sensitive, expected):
-            actual = {str(q) for q in path.glob(pattern, case_sensitive=case_sensitive)}
-            expected = {str(P(self.base, q)) for q in expected}
-            self.assertEqual(actual, expected)
-        path = P(self.base)
-        _check(path, "DIRB/FILE*", True, [])
-        _check(path, "DIRB/FILE*", False, ["dirB/fileB"])
-        _check(path, "dirb/file*", True, [])
-        _check(path, "dirb/file*", False, ["dirB/fileB"])
-
     def test_info_exists(self):
         p = self.cls(self.base)
         self.assertTrue(p.info.exists())