func()

in rate/rate.go [153:188]

• 27 lines of code
• 9 McCabe index (conditional complexity)

func (r *Reservation) CancelAt(now time.Time) {
	if !r.ok {
		return
	}

	r.lim.mu.Lock()
	defer r.lim.mu.Unlock()

	if r.lim.limit == Inf || r.tokens == 0 || r.timeToAct.Before(now) {
		return
	}

	// calculate tokens to restore
	// The duration between lim.lastEvent and r.timeToAct tells us how many tokens were reserved
	// after r was obtained. These tokens should not be restored.
	restoreTokens := float64(r.tokens) - r.limit.tokensFromDuration(r.lim.lastEvent.Sub(r.timeToAct))
	if restoreTokens <= 0 {
		return
	}
	// advance time to now
	now, _, tokens := r.lim.advance(now)
	// calculate new number of tokens
	tokens += restoreTokens
	if burst := float64(r.lim.burst); tokens > burst {
		tokens = burst
	}
	// update state
	r.lim.last = now
	r.lim.tokens = tokens
	if r.timeToAct == r.lim.lastEvent {
		prevEvent := r.timeToAct.Add(r.limit.durationFromTokens(float64(-r.tokens)))
		if !prevEvent.Before(now) {
			r.lim.lastEvent = prevEvent
		}
	}
}