clock

type Clock interface {
	PassiveClock
	// After returns the channel of a new Timer.
	// This method does not allow to free/GC the backing timer before it fires. Use
	// NewTimer instead.
	After(d time.Duration) <-chan time.Time
	// NewTimer returns a new Timer.
	NewTimer(d time.Duration) Timer
	// Sleep sleeps for the provided duration d.
	// Consider making the sleep interruptible by using 'select' on a context channel and a timer channel.
	Sleep(d time.Duration)
	// Tick returns the channel of a new Ticker.
	// This method does not allow to free/GC the backing ticker. Use
	// NewTicker from WithTicker instead.
	Tick(d time.Duration) <-chan time.Time
}

type PassiveClock interface {
	Now() time.Time
	Since(time.Time) time.Duration
}

type RealClock struct{}

type Ticker interface {
	C() <-chan time.Time
	Stop()
}

type Timer interface {
	C() <-chan time.Time
	Stop() bool
	Reset(d time.Duration) bool
}

type WithDelayedExecution interface {
	Clock
	// AfterFunc executes f in its own goroutine after waiting
	// for d duration and returns a Timer whose channel can be
	// closed by calling Stop() on the Timer.
	AfterFunc(d time.Duration, f func()) Timer
}

type WithTicker interface {
	Clock
	// NewTicker returns a new Ticker.
	NewTicker(time.Duration) Ticker
}

type WithTickerAndDelayedExecution interface {
	WithTicker
	// AfterFunc executes f in its own goroutine after waiting
	// for d duration and returns a Timer whose channel can be
	// closed by calling Stop() on the Timer.
	AfterFunc(d time.Duration, f func()) Timer
}