code: func (f *fakeTimer) Reset(d time.Duration) bool {
  	f.fakeClock.lock.Lock()
  	defer f.fakeClock.lock.Unlock()
  
  	active := !f.waiter.fired
  
  	f.waiter.fired = false
  	f.waiter.targetTime = f.fakeClock.time.Add(d)
  
  	return active
  }
docs: // Reset resets the timer to the fake clock's "now" + d. It returns true if the timer has not yet
  // fired, or false otherwise.