mclock

type AbsTime ¶

type AbsTime int64

AbsTime represents absolute monotonic time.

func Now() AbsTime

func (t AbsTime) Add(d time.Duration) AbsTime

func (t AbsTime) Sub(t2 AbsTime) time.Duration

type Alarm ¶ added in v1.11.0

type Alarm struct {
	// contains filtered or unexported fields
}

Alarm sends timed notifications on a channel. This is very similar to a regular timer, but is easier to use in code that needs to re-schedule the same timer over and over.

When scheduling an Alarm, the channel returned by C() will receive a value no later than the scheduled time. An Alarm can be reused after it has fired and can also be canceled by calling Stop.

func NewAlarm(clock Clock) *Alarm

func (e *Alarm) C() <-chan struct{}

func (e *Alarm) Schedule(time AbsTime)

func (e *Alarm) Stop()

type ChanTimer ¶ added in v1.9.11

type ChanTimer interface {
	Timer

	// The channel returned by C receives a value when the timer expires.
	C() <-chan AbsTime
	// Reset reschedules the timer with a new timeout.
	// It should be invoked only on stopped or expired timers with drained channels.
	Reset(time.Duration)
}

ChanTimer is a cancellable event created by NewTimer.

type Clock ¶ added in v1.8.14

type Clock interface {
	Now() AbsTime
	Sleep(time.Duration)
	NewTimer(time.Duration) ChanTimer
	After(time.Duration) <-chan AbsTime
	AfterFunc(d time.Duration, f func()) Timer
}

The Clock interface makes it possible to replace the monotonic system clock with a simulated clock.

type Simulated ¶ added in v1.8.14

type Simulated struct {
	// contains filtered or unexported fields
}

Simulated implements a virtual Clock for reproducible time-sensitive tests. It simulates a scheduler on a virtual timescale where actual processing takes zero time.

The virtual clock doesn't advance on its own, call Run to advance it and execute timers. Since there is no way to influence the Go scheduler, testing timeout behaviour involving goroutines needs special care. A good way to test such timeouts is as follows: First perform the action that is supposed to time out. Ensure that the timer you want to test is created. Then run the clock until after the timeout. Finally observe the effect of the timeout using a channel or semaphore.

func (s *Simulated) ActiveTimers() int

func (s *Simulated) After(d time.Duration) <-chan AbsTime

func (s *Simulated) AfterFunc(d time.Duration, fn func()) Timer

func (s *Simulated) NewTimer(d time.Duration) ChanTimer

func (s *Simulated) Now() AbsTime

func (s *Simulated) Run(d time.Duration)

func (s *Simulated) Sleep(d time.Duration)

func (s *Simulated) WaitForTimers(n int)

type System ¶ added in v1.8.14

type System struct{}

System implements Clock using the system clock.

func (c System) After(d time.Duration) <-chan AbsTime

func (c System) AfterFunc(d time.Duration, f func()) Timer

func (c System) NewTimer(d time.Duration) ChanTimer

func (c System) Now() AbsTime

func (c System) Sleep(d time.Duration)

type Timer ¶ added in v1.9.4

type Timer interface {
	// Stop cancels the timer. It returns false if the timer has already
	// expired or been stopped.
	Stop() bool
}

Timer is a cancellable event created by AfterFunc.