fix: auto fill serialize/deserialize for classes (#2120)

Note this method is being called in 3 places:
one in MessageClassProcessor and 2 in NetworkBehaviorProcessor.

The NetworkBehaviorProcess is really a don't care, this condition cannot happen since it would not be invoked unless the class extends from NetworkBehavior. In this case, it will always resolve.
but even if it does not resolve, they handle the null case gracefully by not calling the base method.

MessageClassProcessor also calls this method, and if it is null it does not call the base method. That is precisely the behavior we want to resolve #2117

so all 3 places are perfectly fine receiving null.

The only way to trigger the error was #2117

I renamed the method to make it clearer that this may not find the method in the parent class.

Assets/Mirror/Editor/Weaver/Processors/MessageClassProcessor.cs

@@ -110,7 +110,7 @@ static void CallWriter(ILProcessor worker, FieldDefinition field)
 
         static void CallBase(TypeDefinition td, ILProcessor worker, string name)
         {
-            MethodReference method = Resolvers.ResolveMethodInParents(td.BaseType, Weaver.CurrentAssembly, name);
+            MethodReference method = Resolvers.TryResolveMethodInParents(td.BaseType, Weaver.CurrentAssembly, name);
             if (method != null)
             {
                 // base

Assets/Mirror/Editor/Weaver/Processors/NetworkBehaviourProcessor.cs

@@ -371,7 +371,7 @@ void GenerateSerialization()
             VariableDefinition dirtyLocal = new VariableDefinition(Weaver.boolType);
             serialize.Body.Variables.Add(dirtyLocal);
 
-            MethodReference baseSerialize = Resolvers.ResolveMethodInParents(netBehaviourSubclass.BaseType, Weaver.CurrentAssembly, SerializeMethodName);
+            MethodReference baseSerialize = Resolvers.TryResolveMethodInParents(netBehaviourSubclass.BaseType, Weaver.CurrentAssembly, SerializeMethodName);
             if (baseSerialize != null)
             {
                 // base
@@ -730,7 +730,7 @@ void GenerateDeSerialization()
             VariableDefinition dirtyBitsLocal = new VariableDefinition(Weaver.int64Type);
             serialize.Body.Variables.Add(dirtyBitsLocal);
 
-            MethodReference baseDeserialize = Resolvers.ResolveMethodInParents(netBehaviourSubclass.BaseType, Weaver.CurrentAssembly, DeserializeMethodName);
+            MethodReference baseDeserialize = Resolvers.TryResolveMethodInParents(netBehaviourSubclass.BaseType, Weaver.CurrentAssembly, DeserializeMethodName);
             if (baseDeserialize != null)
             {
                 // base

Assets/Mirror/Editor/Weaver/Resolvers.cs

@@ -39,11 +39,10 @@ public static MethodReference ResolveMethod(TypeReference t, AssemblyDefinition
             return null;
         }
 
-        public static MethodReference ResolveMethodInParents(TypeReference tr, AssemblyDefinition scriptDef, string name)
+        public static MethodReference TryResolveMethodInParents(TypeReference tr, AssemblyDefinition scriptDef, string name)
         {
             if (tr == null)
             {
-                Weaver.Error($"Cannot resolve method {name} without a type");
                 return null;
             }
             foreach (MethodDefinition methodRef in tr.Resolve().Methods)
@@ -53,8 +52,9 @@ public static MethodReference ResolveMethodInParents(TypeReference tr, AssemblyD
                     return scriptDef.MainModule.ImportReference(methodRef);
                 }
             }
+
             // Could not find the method in this class,  try the parent
-            return ResolveMethodInParents(tr.Resolve().BaseType, scriptDef, name);
+            return TryResolveMethodInParents(tr.Resolve().BaseType, scriptDef, name);
         }
 
         // System.Byte[] arguments need a version with a string

Assets/Mirror/Tests/Editor/MessageBaseTests.cs

@@ -40,6 +40,16 @@ struct WovenTestMessage : IMessageBase
         public void Serialize(NetworkWriter writer) { }
     }
 
+    class ArrayIntIMessage : IMessageBase
+    {
+        public int[] array;
+
+        // Mirror will fill out these empty methods
+        public void Deserialize(NetworkReader reader) { }
+        public void Serialize(NetworkWriter writer) { }
+    }
+
+
     [TestFixture]
     public class MessageBaseTests
     {
@@ -62,5 +72,21 @@ public void WovenSerializationBodyRoundtrip()
             Assert.AreEqual("2", t.StringValue);
             Assert.AreEqual(3.3, t.DoubleValue);
         }
+
+        [Test]
+        public void TestIntArrayInIMessageBase()
+        {
+            ArrayIntIMessage intMessage = new ArrayIntIMessage
+            {
+                array = new[] { 3, 4, 5 }
+            };
+
+            byte[] data = MessagePacker.Pack(intMessage);
+
+            ArrayIntIMessage unpacked = MessagePacker.Unpack<ArrayIntIMessage>(data);
+
+            Assert.That(unpacked.array, Is.EquivalentTo(new int[] { 3, 4, 5 }));
+        }
+
     }
 }