Introduce IsExpendablePod helper function

Change-Id: I899abc73b6de8906a29df0453559545c1cd0a0e5

cluster-autoscaler/core/utils/expendable.go

@@ -55,9 +55,14 @@ func FilterOutExpendableAndSplit(unschedulableCandidates []*apiv1.Pod, nodes []*
 func FilterOutExpendablePods(pods []*apiv1.Pod, expendablePodsPriorityCutoff int) []*apiv1.Pod {
 	var result []*apiv1.Pod
 	for _, pod := range pods {
-		if pod.Spec.Priority == nil || int(*pod.Spec.Priority) >= expendablePodsPriorityCutoff {
+		if !IsExpendablePod(pod, expendablePodsPriorityCutoff) {
 			result = append(result, pod)
 		}
 	}
 	return result
 }
+
+// IsExpendablePod tests if pod is expendable for give priority cutoff
+func IsExpendablePod(pod *apiv1.Pod, expendablePodsPriorityCutoff int) bool {
+	return pod.Spec.Priority != nil && int(*pod.Spec.Priority) < expendablePodsPriorityCutoff
+}

cluster-autoscaler/core/utils/expendable_test.go

@@ -86,5 +86,22 @@ func TestFilterOutExpendablePods(t *testing.T) {
 	assert.Equal(t, p1, res[0])
 	assert.Equal(t, p2, res[1])
 	assert.Equal(t, podWaitingForPreemption2, res[2])
+}
+
+func TestIsExpendablePod(t *testing.T) {
+	pod1 := BuildTestPod("p1", 1500, 200000)
+	pod2 := BuildTestPod("w1", 1500, 200000)
+	var priority1 int32 = -10
+	pod2.Spec.Priority = &priority1
+	pod2.Status.NominatedNodeName = "node1"
+
+	assert.False(t, IsExpendablePod(pod1, 0))
+	assert.False(t, IsExpendablePod(pod1, -9))
+	assert.False(t, IsExpendablePod(pod1, -10))
+	assert.False(t, IsExpendablePod(pod1, -11))
+	assert.True(t, IsExpendablePod(pod2, 0))
+	assert.True(t, IsExpendablePod(pod2, -9))
+	assert.False(t, IsExpendablePod(pod2, -10))
+	assert.False(t, IsExpendablePod(pod2, -11))
 
 }