Add a new method -- ReleaseWaitAllWorkersExit() for waiting all worke…

ants.go

@@ -124,6 +124,11 @@ func Release() {
 	defaultAntsPool.Release()
 }
 
+// ReleaseWaitAllWorkersExit Closes the default pool and wait all workers exit.
+func ReleaseWaitAllWorkersExit() {
+	defaultAntsPool.ReleaseWaitAllWorkersExit()
+}
+
 // Reboot reboots the default pool.
 func Reboot() {
 	defaultAntsPool.Reboot()

ants_test.go

@@ -846,3 +846,28 @@ func TestReleaseTimeout(t *testing.T) {
 	err = pf.ReleaseTimeout(2 * time.Second)
 	assert.NoError(t, err)
 }
+
+func TestReleaseWaitAllWorkersExit(t *testing.T) {
+	p, _ := NewPool(10)
+	for i := 0; i < 5; i++ {
+		_ = p.Submit(func() {
+			time.Sleep(time.Second)
+		})
+	}
+	assert.NotZero(t, p.Running())
+	p.ReleaseWaitAllWorkersExit()
+	assert.Zero(t, p.running)
+}
+
+func TestReleaseWaitAllWorkersExitDefaultPool(t *testing.T) {
+
+	beforeGoNum := runtime.NumGoroutine()
+	defaultAntsPool, _ = NewPool(DefaultAntsPoolSize)
+	afterGoNum := runtime.NumGoroutine()
+	assert.Equal(t, beforeGoNum+1, afterGoNum)
+
+	ReleaseWaitAllWorkersExit()
+	endGoNum := runtime.NumGoroutine()
+	assert.Equal(t, beforeGoNum, endGoNum)
+
+}

pool.go

@@ -253,6 +253,24 @@ func (p *Pool) ReleaseTimeout(timeout time.Duration) error {
 	return ErrTimeout
 }
 
+// ReleaseWaitAllWorkersExit is like Release, but it will wait all workers to exit.
+func (p *Pool) ReleaseWaitAllWorkersExit() {
+	if p.IsClosed() || p.stopHeartbeat == nil {
+		return
+	}
+
+	p.stopHeartbeat()
+	p.stopHeartbeat = nil
+	p.Release()
+
+	for {
+		if p.Running() == 0 && atomic.LoadInt32(&p.heartbeatDone) == 1 {
+			return
+		}
+		time.Sleep(10 * time.Millisecond)
+	}
+}
+
 // Reboot reboots a closed pool.
 func (p *Pool) Reboot() {
 	if atomic.CompareAndSwapInt32(&p.state, CLOSED, OPENED) {