fix remove hostnames

internal/mode/static/state/graph/route_common.go

@@ -344,24 +344,24 @@ func bindRoutesToListeners(
 
 	isolateL7RouteListeners(routes, gw.Listeners)
 
-	l4routes := make([]*L4Route, 0, len(l4Routes))
+	layer4routes := make([]*L4Route, 0, len(l4Routes))
 	for _, r := range l4Routes {
-		l4routes = append(l4routes, r)
+		layer4routes = append(layer4routes, r)
 	}
 
 	// Sort the slice by timestamp and name so that we process the routes in the priority order
-	sort.Slice(l4routes, func(i, j int) bool {
-		return ngfSort.LessClientObject(l4routes[i].Source, l4routes[j].Source)
+	sort.Slice(layer4routes, func(i, j int) bool {
+		return ngfSort.LessClientObject(layer4routes[i].Source, layer4routes[j].Source)
 	})
 
 	// portHostnamesMap exists to detect duplicate hostnames on the same port
 	portHostnamesMap := make(map[string]struct{})
 
-	for _, r := range l4routes {
+	for _, r := range layer4routes {
 		bindL4RouteToListeners(r, gw, namespaces, portHostnamesMap)
 	}
 
-	isolateL4RouteListeners(l4routes, gw.Listeners)
+	isolateL4RouteListeners(layer4routes, gw.Listeners)
 }
 
 // isolateL7RouteListeners ensures listener isolation for all L7Routes.
@@ -395,7 +395,7 @@ func isolateHostnamesForParentRefs(parentRef []ParentRef, listenerHostnameMap ma
 	for _, ref := range parentRef {
 		acceptedHostnames := ref.Attachment.AcceptedHostnames
 
-		hostnamesToRemoves := make([]string, 0, len(acceptedHostnames))
+		hostnamesToRemoves := make(map[string]struct{}, len(acceptedHostnames))
 		for listenerName, hostnames := range acceptedHostnames {
 			if len(hostnames) == 0 {
 				continue
@@ -407,7 +407,7 @@ func isolateHostnamesForParentRefs(parentRef []ParentRef, listenerHostnameMap ma
 						continue
 					}
 					if h == lHostname && listenerName != lName {
-						hostnamesToRemoves = append(hostnamesToRemoves, h)
+						hostnamesToRemoves[h] = struct{}{}
 					}
 				}
 			}
@@ -419,18 +419,11 @@ func isolateHostnamesForParentRefs(parentRef []ParentRef, listenerHostnameMap ma
 }
 
 // removeHostnames removes the hostnames that are part of toRemove slice.
-func removeHostnames(hostnames []string, toRemove []string) []string {
+func removeHostnames(hostnames []string, toRemove map[string]struct{}) []string {
 	result := make([]string, 0, len(hostnames))
-	for _, h := range hostnames {
-		keep := true
-		for _, r := range toRemove {
-			if h == r {
-				keep = false
-				break
-			}
-		}
-		if keep {
-			result = append(result, h)
+	for _, hostname := range hostnames {
+		if _, exists := toRemove[hostname]; !exists {
+			result = append(result, hostname)
 		}
 	}
 	return result

internal/mode/static/state/graph/route_common_test.go

@@ -2680,25 +2680,33 @@ func TestRemoveHostnames(t *testing.T) {
 	tests := []struct {
 		name              string
 		hostnames         []string
-		removeHostnames   []string
+		removeHostnames   map[string]struct{}
 		expectedHostnames []string
 	}{
 		{
-			name:              "remove multiple hostnames",
-			hostnames:         []string{"foo.example.com", "bar.example.com", "bar.com", "*.wildcard.com"},
-			removeHostnames:   []string{"foo.example.com", "bar.example.com"},
+			name:      "remove multiple hostnames",
+			hostnames: []string{"foo.example.com", "bar.example.com", "bar.com", "*.wildcard.com"},
+			removeHostnames: map[string]struct{}{
+				"foo.example.com": {},
+				"bar.example.com": {},
+			},
 			expectedHostnames: []string{"bar.com", "*.wildcard.com"},
 		},
 		{
-			name:              "remove all hostnames",
-			hostnames:         []string{"foo.example.com", "bar.example.com", "bar.com", "*.wildcard.com"},
-			removeHostnames:   []string{"foo.example.com", "bar.example.com", "bar.com", "*.wildcard.com"},
+			name:      "remove all hostnames",
+			hostnames: []string{"foo.example.com", "bar.example.com", "bar.com", "*.wildcard.com"},
+			removeHostnames: map[string]struct{}{
+				"foo.example.com": {},
+				"bar.example.com": {},
+				"bar.com":         {},
+				"*.wildcard.com":  {},
+			},
 			expectedHostnames: []string{},
 		},
 		{
 			name:              "remove no hostnames",
 			hostnames:         []string{"foo.example.com", "bar.example.com", "bar.com", "*.wildcard.com"},
-			removeHostnames:   []string{},
+			removeHostnames:   map[string]struct{}{},
 			expectedHostnames: []string{"foo.example.com", "bar.example.com", "bar.com", "*.wildcard.com"},
 		},
 	}