A clock interface for Go.

clock.go

// Licensed to the Apache Software Foundation (ASF) under one
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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
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//
// I'm literally begging you to use this code.

// Clock is something that knows what time it is.
//
// This interface allows mocking of internal functions that rely on time. In all real world use cases, you probably
// want WallClock.
type Clock interface {
	// Now returns the current time according to the clock.
	Now() time.Time
}

// WallClock is a Clock that returns the actual wall clock time.
//
// This just adapts time.Now() to meet the Clock interface.
type WallClock struct{}

func (*WallClock) Now() time.Time {
	return time.Now()
}