A clock for injecting deterministic times during unit tests and real times in production.

clock.go

package timex

import "time"

type Clock interface {
	Now() time.Time
	Sleep(d time.Duration)
}

type SystemClock struct{}

func (s *SystemClock) Now() time.Time        { return time.Now() }
func (s *SystemClock) Sleep(d time.Duration) { time.Sleep(d) }

type StaticClock struct {
	Time time.Time
}

func (s *StaticClock) Now() time.Time        { return s.Time }
func (s *StaticClock) Sleep(d time.Duration) { s.Time = s.Time.Add(d) }

I wrote this code and I assign it to the public domain. Use it in good health!