Modify StringSet.Delete to return if found

Encapsulates this usage:

  if set.Contains("foo") {
      set.Delete("foo")
      ...
  }

to be atomic with slight efficiency gain.

Signed-off-by: Tom Pantelis <[email protected]>

pkg/routeagent/controllers/route/route.go

@@ -588,8 +588,7 @@ func (r *Controller) handleRemovedPod(obj interface{}) {
 	klog.V(log.DEBUG).Infof("Removing podIP in route controller %v", obj)
 	pod := obj.(*k8sv1.Pod)
 
-	if r.remoteVTEPs.Contains(pod.Status.HostIP) {
-		r.remoteVTEPs.Delete(pod.Status.HostIP)
+	if r.remoteVTEPs.Delete(pod.Status.HostIP) {
 		r.gwVxLanMutex.Lock()
 		defer r.gwVxLanMutex.Unlock()
 

pkg/util/stringset.go

@@ -39,11 +39,13 @@ func (set *StringSet) Size() int {
 	return len(set.set)
 }
 
-func (set *StringSet) Delete(s string) {
+func (set *StringSet) Delete(s string) bool {
 	set.syncMutex.Lock()
 	defer set.syncMutex.Unlock()
 
+	_, found := set.set[s]
 	delete(set.set, s)
+	return found
 }
 
 func (set *StringSet) Elements() []string {

pkg/util/stringset_test.go

@@ -40,14 +40,20 @@ var _ = Describe("StringSet", func() {
 		})
 	})
 
-	When("a string is deleted", func() {
-		It("should no longer be observed in the set", func() {
-			set.Delete("192.168.2.0/24")
+	When("an existing string is deleted", func() {
+		It("should return true and no longer be observed in the set", func() {
+			Expect(set.Delete("192.168.2.0/24")).To(BeTrue())
 			Expect(set.Contains("192.168.2.0/24")).To(BeFalse())
 			Expect(set.Size()).To(Equal(1))
 		})
 	})
 
+	When("a non-existent string is deleted", func() {
+		It("should return false", func() {
+			Expect(set.Delete("192.168.5.0/24")).To(BeFalse())
+		})
+	})
+
 	When("a string is re-added", func() {
 		It("should be observed in the set", func() {
 			set.Delete("192.168.2.0/24")