Two follow-ups stacked on the FN-4811 active-worktree liveness gate:
1. Stale conflict-path recovery (FN-4813 production failure)
When 'git worktree remove --force' fails with 'fatal: validation failed,
cannot remove working tree', the worktree directory is missing on disk
and the git admin entry is stale. Without this recovery, every retry of
tryCreateWorktree on a stale conflict path failed 3 times with
'automatic cleanup failed', leaving tasks unable to create worktrees.
cleanupConflictingWorktree now catches that specific error class, runs
'git worktree prune' to drop the stale admin entry, best-effort deletes
the branch, and returns success so the caller can proceed.
Implementation note: the original attempt used existsSync(worktreePath)
as a pre-check, but vitest's vi.clearAllMocks() can leave the existsSync
mock returning undefined, causing the new branch to fire inside tests
that didn't expect it and leading to worker OOM in
executor-worktree.test.ts. The error-class-based catch is robust against
mock state and matches the real production failure signal exactly.
2. Collapsed broken FN-4806 nested branches
The previous FN-4806 refactor (commit 087b1a766) accidentally nested the
genuine 'agent finished without calling fn_task_done after N retries'
failure path INSIDE the silent-recovery branch, meaning ordinary
failures were being silently requeued (no status=failed, no onError, no
retry-budget burn) instead of being surfaced.
Restored the clean two-branch structure:
} else if (retryAbortedDueToReclaim) {
// silent recovery (FN-4806)
} else {
// genuine no-fn_task_done exhaustion: mark failed, onError, burn budget
}
Also clears baseCommitSha on silent recovery (matches the parallel
session-start-failure path's metadata clearing).
Tests:
- Adds 'FN-4811 follow-up (FN-4813): recovers from validation failed'
case to active-worktree-removal-liveness.test.ts (12 total cases).
- executor-recovery.test.ts no-fn_task_done reclaim coverage now
asserts baseCommitSha is cleared.
- executor-recovery.test.ts 'does not mark task as failed when invalid
transition error occurs on completion' regression fixed by restoring
the failure-path branch.
- executor-core.test.ts 'still enforces fn_task_done requirement in
fast mode' restored.
Full engine suite: 307 files, 5037 tests pass, 1 skipped. Lint clean.
Fusion-Task-Id: FN-4811
dcd6bf60f3