GH-87695: Fix OSError from pathlib.Path.glob() (GH-104292)

Fix issue where `pathlib.Path.glob()` raised `OSError` when it encountered
a symlink to an overly long path.

Author: barneygale

Lib/pathlib.py

@@ -178,11 +178,11 @@ def _iterate_directories(self, parent_path, scandir):
             for entry in entries:
                 entry_is_dir = False
                 try:
-                    entry_is_dir = entry.is_dir()
+                    entry_is_dir = entry.is_dir(follow_symlinks=False)
                 except OSError as e:
                     if not _ignore_error(e):
                         raise
-                if entry_is_dir and not entry.is_symlink():
+                if entry_is_dir:
                     path = parent_path._make_child_relpath(entry.name)
                     for p in self._iterate_directories(path, scandir):
                         yield p

Lib/test/test_pathlib.py

@@ -1977,6 +1977,15 @@ def my_scandir(path):
             subdir.chmod(000)
             self.assertEqual(len(set(base.glob("*"))), 4)
 
+    @os_helper.skip_unless_symlink
+    def test_glob_long_symlink(self):
+        # See gh-87695
+        base = self.cls(BASE) / 'long_symlink'
+        base.mkdir()
+        bad_link = base / 'bad_link'
+        bad_link.symlink_to("bad" * 200)
+        self.assertEqual(sorted(base.glob('**/*')), [bad_link])
+
     def _check_resolve(self, p, expected, strict=True):
         q = p.resolve(strict)
         self.assertEqual(q, expected)

Misc/NEWS.d/next/Library/2023-05-08-15-39-00.gh-issue-87695.f6iO7v.rst

@@ -0,0 +1,2 @@
+Fix issue where :meth:`pathlib.Path.glob` raised :exc:`OSError` when it
+encountered a symlink to an overly long path.