The subprocess-booting test suites hand-picked fixed ports in a cramped ~3955-4021 range, and
156-schedule-read-path deviated to a RANDOM port (3900 + rand%90) that overlapped those fixed
ports. Under CI load two servers could race on the same port, surfacing as flaky "no such table:
devices" / "FOREIGN KEY constraint failed" (a server answering a request against a half-migrated
or wrong DB). It's environmental — the suites pass locally and in isolation.
Fix: a shared test/helpers/free-port.js (bind :0 on loopback, read the OS-assigned port, release)
called in before() so every suite gets a guaranteed-unique ephemeral port — concurrent suites can
no longer collide, and no one has to hand-assign ports.
- Codemod converted 30 suites: const PORT = <fixed|random> -> let PORT (+ BASE) assigned via
`PORT = await freePort()` at the top of before().
- 3 hand-fixed (different structure): 148-eviction-storm (lowercase `base`), boot-health (no
before() — allocates PORT + a throwaway SEED_PORT inside the test, replacing the hardcoded
3894), totp-keyrotation (no before() — allocates at the test start before bootServer()).
No fixed 39xx/40xx ports remain. Full server suite 435/435; the 4 hand-touched suites pass in
isolation. Pure test-infra change — no app code touched.
Bold: screens sit on the Connect page showing the server URL = paired server-side
but never told, so the app never starts playing.
Flow / gap (Step A):
- CLIENT leaves the Connect page ONLY on the 'device:paired' event — web player
(player/index.html) hides the setup screen; Android ProvisioningActivity.onPaired
launches MainActivity + finish(). That event is the sole signal.
- SERVER pushes 'device:paired' to the device's room from POST /api/provision/pair
(server.js) at pair time — but ONLY reaches a LIVE socket then. The normal
device_id reconnect path emitted device:registered + device:playlist-update but
NOT device:paired. So a screen paired while disconnected, or that reconnects after
pairing (exactly the screens cycling on the Connect page), is paired server-side
(user_id set, receiving playlists) yet never gets device:paired -> stuck on Connect.
Fix (server-only, uses the EXISTING client listener — no client update needed, which
matters because we can't push a client update to stuck screens): on the device_id
reconnect, if the device is paired (user_id set), re-emit 'device:paired'
{device_id, name}. Push-on-pair (server.js) already covers the live-at-pair-time
case; this covers paired-then-reconnect. A paired screen now leaves Connect and
plays on its next reconnect with no client change and no manual re-pair.
Tests (port 3989, real flow): provision -> pair via /api/provision/pair (socket
closed) -> reconnect RECEIVES device:paired (+name +playlist) — the stuck-screen
repro; an unpaired device gets NO device:paired (stays on the pairing flow); the fix
reuses the existing device:paired event (no new protocol). Full suite green serial
AND parallel (220); dbac699 / 404c330 / e734281 intact.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>