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jackandClaude Fable 5
a55a16adcd
The previous commit moved cryptographicIdentities into the persisted IdentityCache, which made the pre-existing off-queue cache access in the save path fatal instead of merely racy: forceSave() -> performSave() read and JSON-encoded `cache` on the caller's thread while a concurrent `queue.async(.barrier)` writer mutated the same dictionary. ThreadSanitizer flags this as a data race in saveIdentityCache(), and because JSONEncoder walks the dictionary storage, an interleaved mutation can spin forever — which is what hung the CI "Run Swift Tests (app)" job (killed at the watchdog timeout). The naive fix (snapshot `cache` under `queue.sync` in forceSave) instead introduced a deadlock: forceSave() is reachable from deinit, and the object's final release can run *on* the identity queue (the fire-and-forget barrier saves capture self), so queue.sync there is a re-entrant same-queue wait -> SIGTRAP. That matched the intermittent crash the hang investigation surfaced. Fix: - Split persistence into persist(snapshot:) which encodes/seals/writes a by-value IdentityCache snapshot, decoupled from reading `cache`. - saveIdentityCache() (only ever called inside a barrier writer) passes `cache` directly — already serialized, race-free. - forceSave() now snapshots + persists inside `queue.async(flags:.barrier)` (async, never sync): the read is on the barrier context so it never races an in-flight write, and being async it can't deadlock when invoked from deinit running on the queue. Durability is unaffected: every mutating API already persists inline within its own barrier, so forceSave is a belt-and-suspenders flush. Test: test_concurrentUpsertsAndForceSaveDoNotRaceOrHang hammers concurrent upserts interleaved with forceSave; it reproduces the data race under `--sanitize=thread` on the old code (SecureIdentityStateManager.swift:250) and passes cleanly with the fix. A lock-guarded LockedKeychain double is used so the test exercises the manager's own cache race rather than the non-thread-safe MockKeychain. Verified green over repeated `swift test --parallel` runs both with and without --enable-code-coverage. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>