test(NetworkManagerHUD): add unit test

Added unit test for the NetworkManagersHUDs lifecycle and attributes.

Not sure about the OnGUI Methods. Found some workaround by using delegates but could be overengineered and not suitable.

Author: Nietod

Assets/Mirror/Core/NetworkManagerHUD.cs

@@ -9,12 +9,14 @@ namespace Mirror
     [HelpURL("https://mirror-networking.gitbook.io/docs/components/network-manager-hud")]
     public class NetworkManagerHUD : MonoBehaviour
     {
-        NetworkManager manager;
+        // internal so we can access it during unit tests
+        internal NetworkManager manager;
 
         public int offsetX;
         public int offsetY;
 
-        void Awake()
+        // internal so we can access it during unit tests
+        internal void Awake()
         {
             manager = GetComponent<NetworkManager>();
         }

Assets/Mirror/Tests/Editor/NetworkManagerHUD.meta

@@ -0,0 +1,55 @@
+using NUnit.Framework;
+using UnityEngine;
+
+namespace Mirror.Tests
+{
+    public class NetworkManagerHUDTest : MirrorEditModeTest
+    {
+        [SetUp]
+        public override void SetUp()
+        {
+            base.SetUp();
+        }
+
+        [TearDown]
+        public override void TearDown()
+        {
+            base.TearDown();
+        }
+
+        [Test]
+        public void NetworkManagerHUDAttributesTest()
+        {
+            CreateGameObject(out GameObject manager, out NetworkManagerHUD managerHUD);
+
+            NetworkManagerHUD[] allHUDs = manager.GetComponents<NetworkManagerHUD>();
+
+            // Check if [RequireComponent(typeof(NetworkManager))] works
+            Assert.That(manager.GetComponent<NetworkManager>(), Is.Not.Null);
+            Assert.That(allHUDs.Length, Is.EqualTo(1));
+
+            manager.AddComponent<NetworkManagerHUD>();
+            allHUDs = manager.GetComponents<NetworkManagerHUD>();
+
+            // Check if [DisallowMultipleComponent] works
+            Assert.That(allHUDs.Length, Is.EqualTo(1));
+            Assert.That(allHUDs[0], Is.SameAs(managerHUD));
+        }
+
+        [Test]
+        public void NetworkManagerHUDLifecycleTest()
+        {
+            CreateGameObject(out GameObject managerGO, out NetworkManager networkManager);
+
+            NetworkManagerHUD managerHUD = managerGO.AddComponent<NetworkManagerHUD>();
+
+            Assert.That(managerHUD.manager, Is.Null, "manager should be null before Awake()");
+
+            // Must call Unity lifecycle methods manually in edit mode tests
+            managerHUD.Awake();
+
+            Assert.That(managerHUD.manager, Is.Not.Null, "manager should be set after Awake()");
+            //Assert.That(managerHUD.manager, Is.Not.Null, "manager should be set after Awake()");
+        }
+    }
+}