vault-link/frontend/deterministic-tests

Sync test harnesses (API v4)

Run the complete harness check from any working directory:

E2E_WORKERS=2 /path/to/vault-link/scripts/e2e.sh

The E2E_WORKERS variable is the number of fuzz workers / simultaneous scripted tests. The runner builds the server and the three in-scope frontend packages, then runs the harness self-tests, recovery regressions, protocol/real-filesystem tests, scripted scenarios, and seeded fuzz workers. It does not build the Obsidian plugin or CLI application. Install frontend dependencies with npm ci first. Node's built-in WebSocket, Rust, and a C compiler (cc, for test-only exclusive rename and OS-lock primitives on macOS/Linux) are required.

CI installs those dependencies in frontend before invoking the runner. It sets E2E_ARTIFACTS=logs/e2e and uploads that same directory even when a suite fails. The runner owns all test servers; no separate server or legacy cleanup script is needed in the workflow.

Each server gets a fresh temporary database, working directory, and port. Only owned processes are terminated. There is no pkill, fixed database deletion, or shared server PID file. Failing tests and teardown errors give nonzero exits; the remaining suites still run. Logs, concrete fuzz traces, results, and failure snapshots are retained in the printed artifact directory. Snapshots are captured before teardown so cleanup failures retain the original evidence.

Environment options:

• E2E_WORKERS=1: number of fuzz workers / simultaneous scripted tests (max 32).
• E2E_SEED=1: first uint32 seed; workers use successive seeds.
• E2E_ITERATIONS=25: generated conflict scenarios per worker.
• E2E_TIMEOUT_SECONDS=900: timeout for each build/suite/worker command.
• E2E_ARTIFACTS=/absolute/path: optional output directory; defaults to mkdtemp.

Running individual layers

From frontend:

# Rebuild protocol peers and run scripted tests (name filter optional).
npm run test --workspace deterministic-tests -- --filter v4- --concurrency 2

# Adapter/oracle/lifecycle self-tests and strict recovery regressions.
npm run test:harness

# After rebuilding: real worker death, server SIGKILL/restart, CAS/WS ordering,
# and host filesystem contract checks.
npm run test:protocol

npm run build --workspace sync-client --workspace test-client
node test-client/dist/cli.js --seed 42 --iterations 25
node test-client/dist/cli.js --replay /path/to/trace-42.json

test:harness includes strict regressions for engine bugs. A failing default run is not an expected-failure test or a harness skip. See ../test-support/README.md for their scope.

What the scripted runner checks

Real SyncClient instances use the shared v4 adapter in ../test-support. External editor operations and engine filesystem operations are separate: engine writes never generate self-notifications. Editor identity notifications continue while transport is disabled. Delayed notifications can be explicitly queued and flushed. Snapshots and persisted state are deep copies, never shared references.

Scripted and seeded clients explicitly set syncIntervalMs: 0, with assertions that it stays disabled. Barriers observe convergence; they do not wake the engine. Network retry timers remain enabled. Separate fake-clock tests in test-support/polling.test.ts exercise optional periodic reconciliation.

A barrier checks byte-for-byte replica equality and the server's canonical UUID/path map, file bytes, independently computed base/observed hashes, content and manifest CAS parents, event watermark, contiguous event log, and absence of pending requests. Internal recovery files are excluded from the user-visible file list, but are present in failure disk images. Scenario assertions separately check intended content, document identity, or preservation markers; equality alone is not an adequate data-loss oracle.

Clients start disabled. enable-sync waits for the initial sync attempt/retries, except while the server is intentionally paused: that attempt is tracked so a later script step can resume the server. Thus sequential enables really establish a winner. To test independent creates, first bootstrap both clients empty, then disable them and create files. Initial adoption of pre-existing files during bootstrap is a different policy from two already-initialized clients creating distinct UUIDs at one path.

Controls and assertions

• create, update, create-bytes, rename, delete: external editor actions. Editor rename may explicitly replace its target; engine rename never may.
• sync, barrier, enable-sync, disable-sync.
• reset: restart transports; not a crash and not a database reset.
• pause-websocket, resume-websocket: buffer only WS delivery. HTTP catchup remains active; this is deliberately not called "disconnect".
• pause-observation, wait-for-observation, resume-observation: explicitly gate HTTP catchup as well as WS, including replies already in flight. The checkpoint must be exercised and released, and held reads respect cancellation.
• delay-notifications, flush-notifications: delay editor notifications without disabling preservation assertions.
• drop-response: {client, kind: "create" | "content" | "manifest", point: "before" | "after"}. After faults fire only on an Accepted CAS response.
• wait-for-response-drop: explicit checkpoint; every armed fault must fire. Every interrupted request must be retried with an identical request ID, target and body before a different CAS is sent. Fault kinds match exactly.
• rename-next-write: inject an editor rename after the engine's content write, before its metadata save.
• pause-server, resume-server: SIGSTOP/SIGCONT, not a crash.
• crash-server, restart-server: SIGKILL and restart with the same database/port. Server-control scenarios have dedicated processes.
• remember-identity, assert-identity, assert-files, assert-markers.
• assert-documents: a complete expected set of {key, path, content, conflict?} records. Content is text or a byte array. Keys bind UUIDs on the first successful check and must retain them on later checks; new keys cannot reuse deleted UUIDs. conflict: true resolves the UUID-derived conflict name for path.
• assert-consistent can provide verify(state): exact text/bytes, UUID lookups, assertIdentity, and conflictPath(original) for UUID-derived conflict names.

Legacy timing scenarios are retained. Prefer explicit fault checkpoints and barriers for new tests. Only known coherent-scan races and actually injected transient network errors may retry; they still must converge before the deadline. Other background errors, unhandled rejections, and cleanup failures fail the run.

Reproducibility limits

Seeds and JSON traces reproduce harness choices and logical actions. They do not control the OS scheduler, server thread scheduling, or production-generated UUIDs. The recovery sweep enumerates adapter/save boundaries; worker termination proves abrupt runtime loss. Neither is a proof covering every real filesystem or hardware power-loss behavior. Run multiple seeds, repeat timing-sensitive cases, and keep the scenario's independent oracle when reducing a failing trace.