fix(NetworkBehavior): removing NB that belong to another NI from list (…

…#970)

If there are Nested NetworkBehaviours and NetworkIdentity then there can be a problem where the parent NetworkIdentity will find Behaviour that belong to another child NetworkIdentity.

This will remove those NB from the current NI's array and then resize the array to be the correct size

Assets/Mirage/Runtime/NetworkIdentity.cs

@@ -232,24 +232,58 @@ public NetworkBehaviour[] NetworkBehaviours
         {
             get
             {
-                if (networkBehavioursCache != null)
-                    return networkBehavioursCache;
+                if (networkBehavioursCache is null)
+                {
+                    NetworkBehaviour[] components = FindBehaviourForThisIdentity();
 
-                NetworkBehaviour[] components = GetComponentsInChildren<NetworkBehaviour>(true);
 
-#if DEBUG
-                foreach (NetworkBehaviour item in components)
+
+                    if (components.Length > byte.MaxValue)
+                        throw new InvalidOperationException("Only 255 NetworkBehaviour per gameobject allowed");
+
+                    networkBehavioursCache = components;
+                }
+
+                return networkBehavioursCache;
+            }
+        }
+
+        // cache list to call GetComponentsInChildren() with no allocations
+        private static List<NetworkBehaviour> childNetworkBehavioursCache = new List<NetworkBehaviour>();
+
+        /// <summary>
+        /// Removes NetworkBehaviour that belong to another NetworkIdentity from the components array
+        /// <para>
+        ///     If there are nested NetworkIdentities then Behaviour that belong to those Identities will be found by GetComponentsInChildren if the child object is added before the Array is intialized.
+        ///     This method will check each Behaviour to make sure that the Identity is the same as the current Identity, and if it is not remove it from the array
+        /// </para>
+        /// </summary>
+        /// <param name="components"></param>
+        private NetworkBehaviour[] FindBehaviourForThisIdentity()
+        {
+            GetComponentsInChildren<NetworkBehaviour>(true, childNetworkBehavioursCache);
+
+            // start at last so we can remove from end of array instead of start
+            for (int i = childNetworkBehavioursCache.Count - 1; i >= 0; i--)
+            {
+                NetworkBehaviour item = childNetworkBehavioursCache[i];
+                if (item.Identity != this)
                 {
-                    logger.Assert(item.Identity == this, $"Child NetworkBehaviour had a different Identity, this:{name}, Child Identity:{item.Identity.name}");
+                    childNetworkBehavioursCache.RemoveAt(i);
                 }
-#endif
+            }
 
-                if (components.Length > byte.MaxValue)
-                    throw new InvalidOperationException("Only 255 NetworkBehaviour per gameobject allowed");
+            NetworkBehaviour[] components = childNetworkBehavioursCache.ToArray();
 
-                networkBehavioursCache = components;
-                return networkBehavioursCache;
+#if DEBUG
+            // validate the results here (just incase they are wrong)
+            // we only need to do this in debug mode because results should be right
+            foreach (NetworkBehaviour item in components)
+            {
+                logger.Assert(item.Identity == this, $"Child NetworkBehaviour had a different Identity, this:{name}, Child Identity:{item.Identity.name}");
             }
+#endif
+            return components;
         }
 
         NetworkVisibility _visibility;