fix: avoid throwing exception when using NetworkList without a NetworkManager (Unity-Technologies#2539)

Author: PitouGames

com.unity.netcode.gameobjects/CHANGELOG.md

@@ -12,6 +12,7 @@ Additional documentation and release notes are available at [Multiplayer Documen
 
 - Removed anoying warnings when using `NetworkList` in offline mode. (#2279)
 - Removed anoying warnings when using `NetworkVariable` in offline mode. (#2279)
+- Fixed usage of `NetworkList` throwing exception when used without a NetworkManager in scene. (#2539)
 
 ## [1.5.2] - 2023-07-24
 

com.unity.netcode.gameobjects/Runtime/NetworkVariable/Collections/NetworkList.cs

@@ -371,7 +371,7 @@ public IEnumerator<T> GetEnumerator()
         public void Add(T item)
         {
             // check write permissions
-            if (!CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
+            if (m_NetworkBehaviour && !CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
             {
                 throw new InvalidOperationException("Client is not allowed to write to this NetworkList");
             }
@@ -392,7 +392,7 @@ public void Add(T item)
         public void Clear()
         {
             // check write permissions
-            if (!CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
+            if (m_NetworkBehaviour && !CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
             {
                 throw new InvalidOperationException("Client is not allowed to write to this NetworkList");
             }
@@ -418,7 +418,7 @@ public bool Contains(T item)
         public bool Remove(T item)
         {
             // check write permissions
-            if (!CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
+            if (m_NetworkBehaviour && !CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
             {
                 throw new InvalidOperationException("Client is not allowed to write to this NetworkList");
             }
@@ -453,7 +453,7 @@ public int IndexOf(T item)
         public void Insert(int index, T item)
         {
             // check write permissions
-            if (!CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
+            if (m_NetworkBehaviour && !CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
             {
                 throw new InvalidOperationException("Client is not allowed to write to this NetworkList");
             }
@@ -482,7 +482,7 @@ public void Insert(int index, T item)
         public void RemoveAt(int index)
         {
             // check write permissions
-            if (!CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
+            if (m_NetworkBehaviour && !CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
             {
                 throw new InvalidOperationException("Client is not allowed to write to this NetworkList");
             }
@@ -507,7 +507,7 @@ public T this[int index]
             set
             {
                 // check write permissions
-                if (!CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
+                if (m_NetworkBehaviour && !CanClientWrite(m_NetworkBehaviour.NetworkManager.LocalClientId))
                 {
                     throw new InvalidOperationException("Client is not allowed to write to this NetworkList");
                 }