gh-137976: Exclude symlinks from zoneinfo.available_timezones() results

Lib/test/test_zoneinfo/test_zoneinfo.py

@@ -1941,6 +1941,27 @@ def test_exclude_posixrules(self):
                 actual = self.module.available_timezones()
                 self.assertEqual(actual, expected)
 
+    def test_exclude_symlinks(self):
+        expected = {
+            "America/New_York",
+            "Europe/London",
+        }
+
+        tree = list(expected) + ["localtime"]
+
+        with tempfile.TemporaryDirectory() as td:
+            # Create regular timezone files
+            for key in expected:
+                self.touch_zone(key, td)
+
+            # Create a symlink named "localtime" pointing to one of the timezone files
+            os.symlink("America/New_York", os.path.join(td, "localtime"))
+
+            with self.tzpath_context([td]):
+                actual = self.module.available_timezones()
+                self.assertEqual(actual, expected)
+                self.assertNotIn("localtime", actual)
+
 
 class CTestModule(TestModule):
     module = c_zoneinfo

Lib/zoneinfo/_tzpath.py

@@ -9,7 +9,7 @@ def _reset_tzpath(to=None, stacklevel=4):
     if tzpaths is not None:
         if isinstance(tzpaths, (str, bytes)):
             raise TypeError(
-                f"tzpaths must be a list or tuple, "
+                "tzpaths must be a list or tuple, "
                 + f"not {type(tzpaths)}: {tzpaths!r}"
             )
 
@@ -156,6 +156,10 @@ def valid_key(fpath):
             for file in files:
                 fpath = os.path.join(root, file)
 
+                # Skip symlinks to avoid including files like 'localtime'
+                if os.path.islink(fpath):
+                    continue
+
                 key = os.path.relpath(fpath, start=tz_root)
                 if os.sep != "/":  # pragma: nocover
                     key = key.replace(os.sep, "/")

Misc/NEWS.d/next/Library/2025-08-20-14-01-13.gh-issue-137976.Ql3ZCr.rst

@@ -0,0 +1 @@
+exclude symlinks from zoneinfo.available_timezones() results