GeezerVison is showing github.com — gh-155935: Stop `FileFinder._find_children` retrying a failing directory scan by tobiaspal · Pull Request #155939 · python/cpython
Conversation
tobiaspal
commented
Aug 17, 2026
•
edited
Loading
Uh oh!
There was an error while loading. Please reload this page.
Split the OSError handling: an OSError from next() ends the listing, while one from is_dir() or is_file() skips just that entry.
FileFinder._find_children() (added by gh-139900 implementing the new PathEntryFinder.discover() API proposed in gh-139899) scans a directory in a while True: loop and ignores any OSError without ending the loop.
The except OSError: pass covers two different failure sources: next(scan_iterator) and the os.DirEntry methods. For a DirEntry method (is_dir()/is_file() racing a deletion), skipping the entry is correct. But when next(scan_iterator) itself fails persistently (stale NFS handle, disconnected removable volume) every retry raises the same OSError again, StopIteration never arrives, and the loop never terminates.
Found via @devdanzin's AI-assisted audit of Lib/; working on it at the PyCon Korea 2026 sprint.
Claude Code helped to write the tests and the fix.
Sorry, something went wrong.
Uh oh!
There was an error while loading. Please reload this page.
…directory scan
Split the `OSError` handling: an `OSError` from `next()` ends the listing, while one from `is_dir()` or `is_file()` skips just that entry.
|
|
@@ -1454,6 +1454,13 @@ def _find_children(self): |
|
|
while True:
|
|
|
try:
|
|
|
entry = next(scan_iterator)
|
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Why not simply entry = next(scan_iterator, None) followed by if entry is None? we're already assuming that the entry is non-None since we do entry.name just after next.
Sorry, something went wrong.
Uh oh!
There was an error while loading. Please reload this page.
Uh oh!
There was an error while loading. Please reload this page.
Assignees
No one assigned
Milestone
No milestone
Development
Successfully merging this pull request may close these issues.
Uh oh!
There was an error while loading. Please reload this page.
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.