fix(mobile-queue): arm retries at the earliest deadline and stop losing or replaying queued audio

apps/mobile-rn/__tests__/retry-scheduler.test.ts

@@ -0,0 +1,191 @@
+import { createRetryScheduler } from '../src/features/recording/retry-scheduler'
+import { createQueueRepository, type KeyValueStorage } from '../src/features/recording/durable-queue-repository'
+
+interface FakeTimer {
+  id: number
+  dueAtMs: number
+  callback: () => void
+}
+
+function fakeClock() {
+  let nowMs = 1_000
+  let nextId = 1
+  const timers = new Map<number, FakeTimer>()
+  return {
+    now: () => nowMs,
+    setTimer: (callback: () => void, delayMs: number): number => {
+      const id = nextId
+      nextId += 1
+      timers.set(id, { id, dueAtMs: nowMs + delayMs, callback })
+      return id
+    },
+    clearTimer: (handle: number): void => {
+      timers.delete(handle)
+    },
+    pending: (): number[] => [...timers.values()].map(timer => timer.dueAtMs).sort((a, b) => a - b),
+    advance(ms: number): void {
+      nowMs += ms
+      for (const timer of [...timers.values()].sort((a, b) => a.dueAtMs - b.dueAtMs)) {
+        if (timer.dueAtMs <= nowMs && timers.has(timer.id)) {
+          timers.delete(timer.id)
+          timer.callback()
+        }
+      }
+    },
+  }
+}
+
+async function flush(): Promise<void> {
+  for (let index = 0; index < 10; index += 1) await Promise.resolve()
+}
+
+describe('retry scheduler', () => {
+  test('keeps the earliest deadline armed and ignores later ones', async () => {
+    const clock = fakeClock()
+    const run = jest.fn(async () => undefined)
+    const scheduler = createRetryScheduler({ ...clock, run })
+
+    scheduler.arm('user', 1_000 + 5_000)
+    scheduler.arm('user', 1_000 + 900_000)
+    expect(scheduler.nextDeadline('user')).toBe(6_000)
+    expect(clock.pending()).toEqual([6_000])
+
+    scheduler.arm('user', 1_000 + 2_000)
+    expect(clock.pending()).toEqual([3_000])
+
+    clock.advance(2_000)
+    await flush()
+    expect(run).toHaveBeenCalledTimes(1)
+    expect(scheduler.nextDeadline('user')).toBeUndefined()
+  })
+
+  test('keeps one timer per key', () => {
+    const clock = fakeClock()
+    const scheduler = createRetryScheduler({ ...clock, run: async () => undefined })
+    scheduler.arm('a', 5_000)
+    scheduler.arm('b', 9_000)
+    expect(clock.pending()).toEqual([5_000, 9_000])
+  })
+
+  test('a request while running causes exactly one follow-up pass and the promise waits for it', async () => {
+    const clock = fakeClock()
+    const releases: Array<() => void> = []
+    const run = jest.fn(() => new Promise<void>(resolve => { releases.push(resolve) }))
+    const scheduler = createRetryScheduler({ ...clock, run })
+
+    let firstDone = false
+    const first = scheduler.requestRun('user').then(() => { firstDone = true })
+    await flush()
+    expect(run).toHaveBeenCalledTimes(1)
+    expect(scheduler.isRunning('user')).toBe(true)
+
+    const second = scheduler.requestRun('user')
+    const third = scheduler.requestRun('user')
+    releases[0]()
+    await flush()
+    expect(run).toHaveBeenCalledTimes(2)
+    expect(firstDone).toBe(false)
+
+    releases[1]()
+    await Promise.all([first, second, third])
+    expect(run).toHaveBeenCalledTimes(2)
+    expect(scheduler.isRunning('user')).toBe(false)
+  })
+
+  test('a timer firing during a pass is not lost', async () => {
+    const clock = fakeClock()
+    const releases: Array<() => void> = []
+    const run = jest.fn(() => new Promise<void>(resolve => { releases.push(resolve) }))
+    const scheduler = createRetryScheduler({ ...clock, run })
+
+    const done = scheduler.requestRun('user')
+    await flush()
+    scheduler.arm('user', clock.now() + 30_000)
+    clock.advance(30_000)
+    releases[0]()
+    await flush()
+    expect(run).toHaveBeenCalledTimes(2)
+    releases[1]()
+    await done
+  })
+
+  test('cancel clears the timer and drops a pending follow-up pass', async () => {
+    const clock = fakeClock()
+    const releases: Array<() => void> = []
+    const run = jest.fn(() => new Promise<void>(resolve => { releases.push(resolve) }))
+    const scheduler = createRetryScheduler({ ...clock, run })
+
+    const done = scheduler.requestRun('user')
+    await flush()
+    void scheduler.requestRun('user')
+    scheduler.arm('user', 50_000)
+    scheduler.cancel('user')
+    expect(clock.pending()).toEqual([])
+    releases[0]()
+    await done
+    expect(run).toHaveBeenCalledTimes(1)
+  })
+
+  test('a failed pass still runs the requested follow-up and reports only a final failure', async () => {
+    const clock = fakeClock()
+    let calls = 0
+    let release: () => void = () => undefined
+    const run = jest.fn(async () => {
+      calls += 1
+      if (calls === 1) {
+        await new Promise<void>(resolve => { release = resolve })
+        throw new Error('storage unavailable')
+      }
+    })
+    const scheduler = createRetryScheduler({ ...clock, run })
+
+    const done = scheduler.requestRun('user')
+    await flush()
+    void scheduler.requestRun('user')
+    release()
+    await expect(done).resolves.toBeUndefined()
+    expect(run).toHaveBeenCalledTimes(2)
+
+    run.mockImplementationOnce(async () => { throw new Error('still down') })
+    await expect(scheduler.requestRun('user')).rejects.toThrow('still down')
+  })
+})
+
+describe('queue repository', () => {
+  function memoryStorage(): KeyValueStorage & { data: Map<string, string> } {
+    const data = new Map<string, string>()
+    return {
+      data,
+      getItem: async key => data.get(key) ?? null,
+      setItem: async (key, value) => { data.set(key, value) },
+      removeItem: async key => { data.delete(key) },
+    }
+  }
+
+  function parse(raw: string | null): Array<{ id: string; n: number }> {
+    return raw === null ? [] : JSON.parse(raw) as Array<{ id: string; n: number }>
+  }
+
+  test('serializes concurrent mutations and removes the key when empty', async () => {
+    const storage = memoryStorage()
+    const repository = createQueueRepository({ storage, key: 'k', parse })
+    await Promise.all([
+      repository.mutate(items => [...items, { id: 'a', n: 1 }]),
+      repository.mutate(items => [...items, { id: 'b', n: 2 }]),
+    ])
+    expect(await repository.read()).toEqual([{ id: 'a', n: 1 }, { id: 'b', n: 2 }])
+    expect(await repository.get('b')).toEqual({ id: 'b', n: 2 })
+    expect(await repository.get('missing')).toBeUndefined()
+
+    await repository.mutate(() => [])
+    expect(storage.data.has('k')).toBe(false)
+  })
+
+  test('a failed mutation does not wedge later writes', async () => {
+    const storage = memoryStorage()
+    const repository = createQueueRepository({ storage, key: 'k', parse })
+    await expect(repository.mutate(() => { throw new Error('bad') })).rejects.toThrow('bad')
+    await repository.mutate(items => [...items, { id: 'a', n: 1 }])
+    expect(await repository.read()).toEqual([{ id: 'a', n: 1 }])
+  })
+})