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diff --git a/vendor/github.com/facebookgo/clock/README.md b/vendor/github.com/facebookgo/clock/README.md new file mode 100644 index 0000000000..5d4f4fe72e --- /dev/null +++ b/vendor/github.com/facebookgo/clock/README.md @@ -0,0 +1,104 @@ +clock [](https://drone.io/github.com/benbjohnson/clock/latest) [](https://coveralls.io/r/benbjohnson/clock?branch=master) [](https://godoc.org/github.com/benbjohnson/clock)  +===== + +Clock is a small library for mocking time in Go. It provides an interface +around the standard library's [`time`][time] package so that the application +can use the realtime clock while tests can use the mock clock. + +[time]: http://golang.org/pkg/time/ + + +## Usage + +### Realtime Clock + +Your application can maintain a `Clock` variable that will allow realtime and +mock clocks to be interchangable. For example, if you had an `Application` type: + +```go +import "github.com/benbjohnson/clock" + +type Application struct { + Clock clock.Clock +} +``` + +You could initialize it to use the realtime clock like this: + +```go +var app Application +app.Clock = clock.New() +... +``` + +Then all timers and time-related functionality should be performed from the +`Clock` variable. + + +### Mocking time + +In your tests, you will want to use a `Mock` clock: + +```go +import ( + "testing" + + "github.com/benbjohnson/clock" +) + +func TestApplication_DoSomething(t *testing.T) { + mock := clock.NewMock() + app := Application{Clock: mock} + ... +} +``` + +Now that you've initialized your application to use the mock clock, you can +adjust the time programmatically. The mock clock always starts from the Unix +epoch (midnight, Jan 1, 1970 UTC). + + +### Controlling time + +The mock clock provides the same functions that the standard library's `time` +package provides. For example, to find the current time, you use the `Now()` +function: + +```go +mock := clock.NewMock() + +// Find the current time. +mock.Now().UTC() // 1970-01-01 00:00:00 +0000 UTC + +// Move the clock forward. +mock.Add(2 * time.Hour) + +// Check the time again. It's 2 hours later! +mock.Now().UTC() // 1970-01-01 02:00:00 +0000 UTC +``` + +Timers and Tickers are also controlled by this same mock clock. They will only +execute when the clock is moved forward: + +``` +mock := clock.NewMock() +count := 0 + +// Kick off a timer to increment every 1 mock second. +go func() { + ticker := clock.Ticker(1 * time.Second) + for { + <-ticker.C + count++ + } +}() +runtime.Gosched() + +// Move the clock forward 10 second. +mock.Add(10 * time.Second) + +// This prints 10. +fmt.Println(count) +``` + + |