Improve error log for duplicate opcode handlers to make locating them…

… easier

WowPacketParser/Parsing/Handler.cs

@@ -70,19 +70,13 @@ private static void LoadHandlersInto(Dictionary<KeyValuePair<ClientVersionBuild,
 
                         var del = (Action<Packet>)Delegate.CreateDelegate(typeof(Action<Packet>), method);
 
-                        if (handlers.ContainsKey(key))
+                        if (handlers.TryGetValue(key, out var existingHandler))
                         {
-                            // @TODO This is a hack to keep things easy regarding declaration of opcodes.
-                            // Ideally, we would split the opcodes into three different enums:
-                            // ClientOpcodes, ServerOpcodes, BidirectionalOpcodes
-                            // The first two are obvious as to what they would contain.
-                            // The last one would be MSG_, UMSG_, TEST_, etc... opcodes
-                            // However that's just too much pain to do considering the mess Blizzard does
-                            // by naming their opcodes sometimes without following their own rules.
                             Direction direction = attr.Opcode.ToString()[0] == 'S' ? Direction.ServerToClient : Direction.ClientToServer;
-                            // ReSharper disable once UseStringInterpolation
-                            Trace.WriteLine(string.Format("Error: (Build: {0}) tried to overwrite delegate for opcode {1} ({2}); new handler: {3}; old handler: {4}",
-                                ClientVersion.Build, Opcodes.GetOpcode(attr.Opcode, direction), attr.Opcode, del.Method, handlers[key].Method));
+                            Trace.WriteLine(
+                                $"Error: (Build: {ClientVersion.Build}) tried to overwrite delegate for opcode {Opcodes.GetOpcode(attr.Opcode, direction)} ({attr.Opcode});"
+                                + $" new handler: {del.Method.DeclaringType}.{del.Method.Name};"
+                                + $" old handler: {existingHandler.Method.DeclaringType}.{existingHandler.Method.Name}");
                             continue;
                         }