Merge pull request #60555 from zhangxiaoyu-zidif/add-unit-test-for-nodenames-slice-comparison

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

add unit test case for nodenames comparison

**What this PR does / why we need it**:
ref https://github.com/kubernetes/kubernetes/pull/60486

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #

**Special notes for your reviewer**:
please merge it after https://github.com/kubernetes/kubernetes/pull/60486

**Release note**:

```release-note
NONE
```

pkg/controller/service/service_controller_test.go

@@ -777,13 +777,21 @@ func TestServiceCache(t *testing.T) {
 //Test a utility functions as its not easy to unit test nodeSyncLoop directly
 func TestNodeSlicesEqualForLB(t *testing.T) {
 	numNodes := 10
-	nArray := make([]*v1.Node, 10)
-
+	nArray := make([]*v1.Node, numNodes)
+	mArray := make([]*v1.Node, numNodes)
 	for i := 0; i < numNodes; i++ {
 		nArray[i] = &v1.Node{}
-		nArray[i].Name = fmt.Sprintf("node1")
+		nArray[i].Name = fmt.Sprintf("node%d", i)
 	}
+	for i := 0; i < numNodes; i++ {
+		mArray[i] = &v1.Node{}
+		mArray[i].Name = fmt.Sprintf("node%d", i+1)
+	}
+
 	if !nodeSlicesEqualForLB(nArray, nArray) {
 		t.Errorf("nodeSlicesEqualForLB() Expected=true Obtained=false")
 	}
+	if nodeSlicesEqualForLB(nArray, mArray) {
+		t.Errorf("nodeSlicesEqualForLB() Expected=false Obtained=true")
+	}
 }