fix: Don't let exceptions in OnNetworkSpawn/OnNetworkDespawn block processing of the next callback. [MTT-1378]

com.unity.netcode.gameobjects/CHANGELOG.md

@@ -12,6 +12,8 @@ Additional documentation and release notes are available at [Multiplayer Documen
 
 - Fixed NetworkManager to cleanup connected client lists after stopping (#1945)
 - Fixed: NetworkHide followed by NetworkShow on the same frame works correctly (#1940)
+- Fixed throwing an exception in OnNetworkSpawn/OnNetworkDespawn causing other OnNetworkSpawn/OnNetworkDespawn calls to not be executed. (#1739)
+
 
 ## [1.0.0-pre.8] - 2022-04-27
 

com.unity.netcode.gameobjects/Runtime/Core/NetworkBehaviour.cs

@@ -435,14 +435,28 @@ internal void InternalOnNetworkSpawn()
             IsSpawned = true;
             InitializeVariables();
             UpdateNetworkProperties();
-            OnNetworkSpawn();
+            try
+            {
+                OnNetworkSpawn();
+            }
+            catch (Exception e)
+            {
+                Debug.LogException(e);
+            }
         }
 
         internal void InternalOnNetworkDespawn()
         {
             IsSpawned = false;
             UpdateNetworkProperties();
-            OnNetworkDespawn();
+            try
+            {
+                OnNetworkDespawn();
+            }
+            catch (Exception e)
+            {
+                Debug.LogException(e);
+            }
         }
 
         /// <summary>

testproject/Assets/Tests/Runtime/OnNetworkSpawnExceptionTests.cs

@@ -0,0 +1,121 @@
+using System;
+using System.Collections;
+using System.Text.RegularExpressions;
+using Unity.Netcode;
+using Unity.Netcode.TestHelpers.Runtime;
+using UnityEngine;
+using UnityEngine.Assertions;
+using UnityEngine.TestTools;
+
+namespace TestProject.RuntimeTests
+{
+
+    public class OnNetworkSpawnThrowsExceptionComponent : NetworkBehaviour
+    {
+        public static int NumClientSpawns = 0;
+        public override void OnNetworkSpawn()
+        {
+            if (IsClient)
+            {
+                ++NumClientSpawns;
+                if (NumClientSpawns > 2)
+                {
+                    throw new Exception("I'm misbehaving");
+                }
+            }
+        }
+    }
+    public class OnNetworkDespawnThrowsExceptionComponent : NetworkBehaviour
+    {
+        public static int NumClientDespawns = 0;
+        public override void OnNetworkDespawn()
+        {
+            if (IsClient)
+            {
+                ++NumClientDespawns;
+                if (NumClientDespawns > 2)
+                {
+                    throw new Exception("I'm misbehaving");
+                }
+            }
+        }
+
+    }
+    public class OnNetworkSpawnExceptionTests : NetcodeIntegrationTest
+    {
+        private GameObject m_Prefab;
+        private GameObject[] m_Objects = new GameObject[5];
+
+        [UnityTest]
+        public IEnumerator WhenOnNetworkSpawnThrowsException_FutureOnNetworkSpawnsAreNotPrevented()
+        {
+            //Spawning was done during setup
+            Assert.AreEqual(5, OnNetworkSpawnThrowsExceptionComponent.NumClientSpawns);
+            yield return null;
+        }
+
+        [UnityTest]
+        public IEnumerator WhenOnNetworkDespawnThrowsException_FutureOnNetworkDespawnsAreNotPrevented()
+        {
+            for (var i = 0; i < 3; ++i)
+            {
+                LogAssert.Expect(LogType.Exception, new Regex("I'm misbehaving"));
+            }
+            //Spawning was done during setup. Now we despawn.
+            for (var i = 0; i < 5; ++i)
+            {
+                m_Objects[i].GetComponent<NetworkObject>().Despawn();
+            }
+
+            var result = new TimeoutHelper();
+            yield return WaitForConditionOrTimeOut(
+                    () => OnNetworkDespawnThrowsExceptionComponent.NumClientDespawns == 5, result);
+            Assert.IsFalse(result.TimedOut);
+        }
+
+        protected override IEnumerator OnSetup()
+        {
+            m_UseHost = false;
+
+            for (var i = 0; i < 3; ++i)
+            {
+                LogAssert.Expect(LogType.Exception, new Regex("I'm misbehaving"));
+            }
+            OnNetworkSpawnThrowsExceptionComponent.NumClientSpawns = 0;
+            OnNetworkDespawnThrowsExceptionComponent.NumClientDespawns = 0;
+            yield return null;
+        }
+
+        protected override IEnumerator OnServerAndClientsConnected()
+        {
+            m_Prefab = new GameObject();
+            var networkObject = m_Prefab.AddComponent<NetworkObject>();
+            m_Prefab.AddComponent<OnNetworkSpawnThrowsExceptionComponent>();
+            m_Prefab.AddComponent<OnNetworkDespawnThrowsExceptionComponent>();
+            NetcodeIntegrationTestHelpers.MakeNetworkObjectTestPrefab(networkObject);
+
+            m_ServerNetworkManager.NetworkConfig.ForceSamePrefabs = false;
+            m_ServerNetworkManager.AddNetworkPrefab(m_Prefab);
+            foreach (var client in m_ClientNetworkManagers)
+            {
+                client.NetworkConfig.ForceSamePrefabs = false;
+                client.AddNetworkPrefab(m_Prefab);
+            }
+
+            for (var i = 0; i < 5; ++i)
+            {
+                var obj = UnityEngine.Object.Instantiate(m_Prefab);
+                m_Objects[i] = obj;
+                obj.GetComponent<NetworkObject>().NetworkManagerOwner = m_ServerNetworkManager;
+                obj.GetComponent<NetworkObject>().Spawn();
+            }
+
+            var result = new TimeoutHelper();
+            yield return WaitForConditionOrTimeOut(
+                () => OnNetworkSpawnThrowsExceptionComponent.NumClientSpawns == 5, result);
+            Assert.IsFalse(result.TimedOut);
+        }
+
+        protected override int NumberOfClients => 1;
+    }
+}