Fix corner case in rated resizer

pond_blackbox_test.go

@@ -190,6 +190,29 @@ func TestTrySubmit(t *testing.T) {
 	assertEqual(t, int32(1), atomic.LoadInt32(&doneCount))
 }
 
+func TestSubmitToIdle(t *testing.T) {
+
+	pool := pond.New(1, 5)
+
+	// Submit a task and wait for it to complete
+	pool.SubmitAndWait(func() {
+		time.Sleep(1 * time.Millisecond)
+	})
+
+	assertEqual(t, int(1), pool.Running())
+	assertEqual(t, int(1), pool.Idle())
+
+	// Submit another task (this one should go to the idle worker)
+	pool.SubmitAndWait(func() {
+		time.Sleep(1 * time.Millisecond)
+	})
+
+	pool.StopAndWait()
+
+	assertEqual(t, int(0), pool.Running())
+	assertEqual(t, int(0), pool.Idle())
+}
+
 func TestRunning(t *testing.T) {
 
 	workerCount := 5

resizer.go

@@ -46,7 +46,7 @@ func RatedResizer(rate int) ResizingStrategy {
 
 func (r *ratedResizer) Resize(runningWorkers, minWorkers, maxWorkers int) bool {
 
-	if r.rate == 1 {
+	if r.rate == 1 || runningWorkers == 0 {
 		return true
 	}
 

resizer_test.go

@@ -9,9 +9,11 @@ func TestRatedResizer(t *testing.T) {
 	resizer := RatedResizer(3)
 
 	assertEqual(t, true, resizer.Resize(0, 0, 10))
-	assertEqual(t, false, resizer.Resize(1, 0, 10))
+	assertEqual(t, true, resizer.Resize(0, 0, 10))
+	assertEqual(t, true, resizer.Resize(1, 0, 10))
 	assertEqual(t, false, resizer.Resize(2, 0, 10))
-	assertEqual(t, true, resizer.Resize(3, 0, 10))
+	assertEqual(t, false, resizer.Resize(3, 0, 10))
+	assertEqual(t, true, resizer.Resize(4, 0, 10))
 }
 
 func TestRatedResizerWithRate1(t *testing.T) {