Address the RED gate cert on PR #5688 (2 BRICK + 1 CORE) and the
incoming Greptile review (1 P1 + 3 P2):
- BRICK-1 (race-safety): drop the mtime heuristic and any age-based
lock removal. Add /api/updates/clear_lock with a fail-closed
fcntl.flock holder probe (refuses if any process still holds the
file, on POSIX). On non-POSIX, fails closed. Touches only
.git/index.lock (the only well-known short-lived lock git creates).
- BRICK-2 (destructive path coupling): remove lock_conflict from the
force-button condition. Add a separate btnClearUpdateLock that calls
/api/updates/clear_lock -- never apply_force_update. The recovery
path never runs checkout/clean/reset --hard.
- CORE-1 (unconditional pre-cleanup): apply_force_update no longer
iterates .git/**/*.lock. Lock cleanup is exclusively the clear_lock
endpoint's job.
- Greptile P1: when a pull-lock error fires after a stash was pushed,
run git stash pop (with apply+drop fallback) so the user's local
modifications aren't stranded in the stash silently. v2 tests
cover the stashed and the clean cases.
- Greptile P2 (broad 'lock file' substring): tightened _GIT_LOCK_SIGNATURES
to specific git error strings ('index.lock': file exists, '.lock':
file exists, 'another git process seems to be running',
'unable to create .git/index.lock') so unrelated ref-transaction
lock-loss messages no longer trigger a lock-conflict response.
- Greptile P2 (redundant git_dir.exists / magic number): both gone as a
side effect of removing the apply_force_update cleanup loop entirely.
Refactor: rebased onto current upstream/master so PR is no longer
'behind' 130 commits.
Tests:
- 14 new v2 tests covering holder probe (true/false/NOGIL probe),
_try_remove_lock (refuse-on-held/success-on-unheld),
apply_clear_lock (success/refused), signature set parameter table
including false-positive class, apply_force_update no-touch
contract, pull-lock stash restore, pull-lock no-stash-when-clean.
- 2 v1 tests removed (they encoded the unsafe behavior).
- 2 v1 parametrize rows dropped (their positive cases relied on the
broad 'lock file' substring).
Closes#5687
e8f7e28a3c