Eliminate ProgressMessage class

Author: CharliePoole

src/NUnitEngine/nunit.engine.core/Communication/Messages/CommandMessage.cs

@@ -8,6 +8,7 @@ namespace NUnit.Engine.Communication.Messages
     public class CommandMessage : TestEngineMessage
     {
         public CommandMessage(string commandName, params object[] arguments)
+            : base(MessageCode.FromCommand(commandName), null)
         {
             CommandName = commandName;
             Arguments = arguments;

src/NUnitEngine/nunit.engine.core/Communication/Messages/MessageCode.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Charlie Poole, Rob Prouse and Contributors. MIT License - see LICENSE.txt
 
+using System;
+
 namespace NUnit.Engine.Communication.Messages
 {
     public class MessageCode
@@ -20,5 +22,32 @@ public class MessageCode
 
         public const string ProgressReport = "PROG";
         public const string CommandResult = "RSLT";
+
+        public static string FromCommand(string command)
+        {
+            switch (command)
+            {
+                case "CreateRunner":
+                    return CreateRunner;
+                case "Load":
+                    return LoadCommand;
+                case "Reload":
+                    return ReloadCommand;
+                case "Unload":
+                    return UnloadCommand;
+                case "Explore":
+                    return ExploreCommand;
+                case "CountTestCases":
+                    return CountCasesCommand;
+                case "Run":
+                    return RunCommand;
+                case "RunAsync":
+                    return RunAsyncCommand;
+                case "Stop":
+                    return RequestStopCommand;
+                default:
+                    throw new ArgumentException("Invalid command", nameof(command));
+            }
+        }
     }
 }

src/NUnitEngine/nunit.engine.core/Communication/Messages/ProgressMessage.cs

@@ -5,21 +5,21 @@
 namespace NUnit.Engine.Communication.Messages
 {
     [Serializable]
-    public abstract class TestEngineMessage
+    public class TestEngineMessage
     {
-    //    public TestEngineMessage(string code, string data)
-    //    {
-    //        Code = code;
-    //        Data = data;
-    //    }
+        public TestEngineMessage(string code, string data)
+        {
+            Code = code;
+            Data = data;
+        }
 
-    //    protected TestEngineMessage() { }
+        protected TestEngineMessage() { }
 
-    //    public string Code { get; }
-    //    public string Data { get; }
+        public string Code { get; }
+        public string Data { get; }
 
-    //    // Alias properties for convenience
-    //    //public string CommandName => Code;
-    //    //public string Argument => Data;
+        // Alias properties for convenience
+        //public string CommandName => Code;
+        //public string Argument => Data;
     }
 }

src/NUnitEngine/nunit.engine.core/Communication/Messages/TestEngineMessage.cs

@@ -129,7 +129,8 @@ private void SendResult(object result)
 
         public void OnTestEvent(string report)
         {
-            var progressMessage = new ProgressMessage(report);
+            //var progressMessage = new ProgressMessage(report);
+            var progressMessage = new TestEngineMessage(MessageCode.ProgressReport, report);
             var bytes = new BinarySerializationProtocol().Encode(progressMessage);
             _clientSocket.Send(bytes);
         }

src/NUnitEngine/nunit.engine.core/Communication/Transports/Tcp/TestAgentTcpTransport.cs

@@ -119,11 +119,10 @@ private TestEngineResult TestRunResult(ITestEventListener listener)
                 if (returnMessage != null)
                     return (TestEngineResult)returnMessage.ReturnValue;
 
-                var progressMessage = receivedMessage as ProgressMessage;
-                if (progressMessage == null)
+                if (receivedMessage.Code == MessageCode.ProgressReport)
+                    listener.OnTestEvent(receivedMessage.Data);
+                else
                     throw new InvalidOperationException($"Expected either a ProgressMessage or a CommandReturnMessage but received a {receivedType}");
-
-                listener.OnTestEvent(progressMessage.Report);
             }
         }
     }