5. 统计协程耗时

此开源图书由ithaiq原创，创作不易转载请注明出处

type MyWaitGroup struct {
	sync.WaitGroup
	cost int64
}

func test1() {
	time.Sleep(time.Second * 3)
}

func test2() {
	time.Sleep(time.Second * 1)
}

func test3() {
	time.Sleep(time.Second * 2)
}

func doWork(wg *MyWaitGroup, fns ...func()) {

	for _, fn := range fns {
		wg.Add(1)
		go func(fn func()) {
			defer wg.Done()
			defer func(t time.Time) {
				wg.cost += time.Since(t).Milliseconds() / 1000
			}(time.Now())
			fn()
		}(fn)
	}
}

func main() {
	now := time.Now()
	var wg MyWaitGroup
	doWork(&wg, test1, test2, test3)
	wg.Wait()
	fmt.Println(time.Since(now).Milliseconds() / 1000)
	fmt.Println(wg.cost)
}

由上可以看出扩展了WaitGroup方法实现