GH-90208: Suppress OSError exceptions from pathlib.Path.glob() (GH-104141)

`pathlib.Path.glob()` now suppresses all OSError exceptions, except
those raised from calling `is_dir()` on the top-level path.

Previously, `glob()` suppressed ENOENT, ENOTDIR, EBADF and ELOOP
errors and their Windows equivalents. PermissionError was also
suppressed unless it occurred when calling `is_dir()` on the
top-level path. However, the selector would abort prematurely
if a PermissionError was raised, and so `glob()` could return
incomplete results.

Lib/test/test_pathlib.py

@@ -1949,33 +1949,19 @@ class _BasePathTest(object):
         P = self.cls
         base = P(BASE) / 'permissions'
         base.mkdir()
+        self.addCleanup(os_helper.rmtree, base)
 
-        file1 = base / "file1"
-        file1.touch()
-        file2 = base / "file2"
-        file2.touch()
+        for i in range(100):
+            link = base / f"link{i}"
+            if i % 2:
+                link.symlink_to(P(BASE, "dirE", "nonexistent"))
+            else:
+                link.symlink_to(P(BASE, "dirC"))
 
-        subdir = base / "subdir"
-
-        file3 = base / "file3"
-        file3.symlink_to(subdir / "other")
-
-        # Patching is needed to avoid relying on the filesystem
-        # to return the order of the files as the error will not
-        # happen if the symlink is the last item.
-        real_scandir = os.scandir
-        def my_scandir(path):
-            with real_scandir(path) as scandir_it:
-                entries = list(scandir_it)
-            entries.sort(key=lambda entry: entry.name)
-            return contextlib.nullcontext(entries)
-
-        with mock.patch("os.scandir", my_scandir):
-            self.assertEqual(len(set(base.glob("*"))), 3)
-            subdir.mkdir()
-            self.assertEqual(len(set(base.glob("*"))), 4)
-            subdir.chmod(000)
-            self.assertEqual(len(set(base.glob("*"))), 4)
+        self.assertEqual(len(set(base.glob("*"))), 100)
+        self.assertEqual(len(set(base.glob("*/"))), 50)
+        self.assertEqual(len(set(base.glob("*/fileC"))), 50)
+        self.assertEqual(len(set(base.glob("*/file*"))), 50)
 
     @os_helper.skip_unless_symlink
     def test_glob_long_symlink(self):