gh-151788: Address review — drop perf comment, tame NEWS wording

- Remove the performance rationale from the inline comment; keep only the
  note explaining the OSError fallback (correctness, not performance).
- Reword the NEWS entry to state the mechanism without magnitude claims.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: mjbommar

Lib/http/server.py

@@ -902,10 +902,9 @@ def list_directory(self, path):
         for entry in entries:
             name = entry.name
             displayname = linkname = name
-            # Append / for directories or @ for symbolic links. Use the cached
-            # os.DirEntry methods to avoid a stat() per entry. Fall back to
-            # False on OSError to mirror os.path.isdir()/islink(), whose result
-            # would otherwise differ (e.g. a symlink to an unreadable target).
+            # Append / for directories or @ for symbolic links. is_dir() and
+            # is_symlink() can raise OSError where os.path.isdir()/islink()
+            # return False, so fall back to False to keep the same behavior.
             try:
                 is_dir = entry.is_dir()
             except OSError:

Misc/NEWS.d/next/Library/2026-06-20-09-00-26.gh-issue-151788.Gr8IxK.rst

@@ -1,5 +1,5 @@
-:class:`http.server.SimpleHTTPRequestHandler` now builds directory listings
-with :func:`os.scandir` instead of :func:`os.listdir` followed by an
-:func:`os.stat` call per entry. This improves the performance of
-:meth:`~http.server.SimpleHTTPRequestHandler.list_directory` on systems with
-slow ``stat`` calls, such as network filesystems.
+:class:`http.server.SimpleHTTPRequestHandler` now uses :func:`os.scandir`
+instead of :func:`os.listdir` to build directory listings, avoiding an
+:func:`os.stat` call per entry. This can improve
+:meth:`~http.server.SimpleHTTPRequestHandler.list_directory` performance where
+``stat`` calls are slow.