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Sarj Sarj Sarj Standards

no-sleep-in-test-body

Avoid fixed timed sleeps directly in test bodies; synchronize on observable behavior or use controlled timers.

noSleepInTestBody Rule source Tests Catalog JSON

Why

Wall-clock delays make test correctness depend on scheduler and machine speed.

Fix

Await the observable signal, or advance fake timers when supported and restore real timers in finally or a teardown hook.

Examples

Before — flagged Do not wait for wall-clock time
src/retry.test.ts
it("retries", async () => {
  await sleep(50);
  expect(done()).toBe(true);
});
After — preferred Advance controlled time and restore real timers
src/retry.test.ts
it("retries", async () => {
  vi.useFakeTimers();
  try {
    const result = retry();
    await vi.advanceTimersByTimeAsync(50);
    await result;
  } finally {
    vi.useRealTimers();
  }
});

Files

**/*.test.***/*.spec.***/tests/****/__tests__/**