Method useFakeTimers

packages/vitest/src/integrations/mock/timers.ts:146–177

()

  }

  useFakeTimers(): void {
    const fakeDate = this._fakingDate || Date.now()
    if (this._fakingDate) {
      resetDate()
      this._fakingDate = null
    }

    if (this._fakingTime) {
      this._clock.uninstall()
    }

    const toFake = Object.keys(this._fakeTimers.timers)
    // Do not mock timers internally used by node by default. It can still be mocked through userConfig.
      .filter(
        timer => timer !== 'nextTick' && timer !== 'queueMicrotask',
      ) as (keyof FakeTimerWithContext['timers'])[]

    if (this._userConfig?.toFake?.includes('nextTick') && isChildProcess()) {
      throw new Error(
        'process.nextTick cannot be mocked inside child_process',
      )
    }

    this._clock = this._fakeTimers.install({
      now: fakeDate,
      ...this._userConfig,
      toFake: this._userConfig?.toFake || toFake,
      ignoreMissingTimers: true,
    })

    this._fakingTime = true
  }

  reset(): void {
    if (this._checkFakeTimers()) {