gh-155935: Stop FileFinder._find_children retrying a failing directory scan - #155939
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tobiaspal wants to merge 1 commit into
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gh-155935: Stop FileFinder._find_children retrying a failing directory scan#155939tobiaspal wants to merge 1 commit into
FileFinder._find_children retrying a failing directory scan#155939tobiaspal wants to merge 1 commit into
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…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.
tobiaspal
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FFY00,
brettcannon,
ericsnowcurrently,
ncoghlan and
warsaw
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August 17, 2026 06:39
picnixz
reviewed
Aug 17, 2026
| @@ -1454,6 +1454,13 @@ def _find_children(self): | |||
| while True: | |||
| try: | |||
| entry = next(scan_iterator) | |||
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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.
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Split the
OSErrorhandling: anOSErrorfromnext()ends the listing, while one fromis_dir()oris_file()skips just that entry.FileFinder._find_children()(added by gh-139900 implementing the newPathEntryFinder.discover()API proposed in gh-139899) scans a directory in awhile True:loop and ignores anyOSErrorwithout ending the loop.The
except OSError: passcovers two different failure sources:next(scan_iterator)and theos.DirEntrymethods. For aDirEntrymethod (is_dir()/is_file()racing a deletion), skipping the entry is correct. But whennext(scan_iterator)itself fails persistently (stale NFS handle, disconnected removable volume) every retry raises the sameOSErroragain,StopIterationnever 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.
FileFinder._find_childrencan loop forever on a persistently failing directory scan #155935