Added unit test for run being the default command

VisualStudio.Tests/OutputHelperTextWriter.cs

@@ -0,0 +1,21 @@
+using System.IO;
+using System.Text;
+using Xunit.Abstractions;
+
+namespace VisualStudio.Tests
+{
+    internal class OutputHelperTextWriter : TextWriter
+    {
+        readonly ITestOutputHelper output;
+
+        public OutputHelperTextWriter(ITestOutputHelper output) => this.output = output;
+
+        public override Encoding Encoding => Encoding.UTF8;
+
+        public override void Write(string value) => WriteLine(value);
+
+        public override void WriteLine(string message) => output.WriteLine(message);
+
+        public override void WriteLine(string format, params object[] args) => output.WriteLine(format, args);
+    }
+}

VisualStudio.Tests/ProgramTests.cs

@@ -0,0 +1,27 @@
+using System.IO;
+using System.Threading.Tasks;
+using Xunit;
+using Xunit.Abstractions;
+
+namespace VisualStudio.Tests
+{
+    public class ProgramTests
+    {
+        readonly TextWriter output;
+
+        public ProgramTests(ITestOutputHelper output) => 
+            this.output = new OutputHelperTextWriter(output);
+
+        [Fact]
+        public async Task when_no_command_specified_run_is_default()
+        {
+            var program = new Program(output, false, "pre");
+
+            var exit = await program.RunAsync();
+
+            Assert.Equal(0, exit);
+
+            Assert.IsType<RunCommand>(program.Command);
+        }
+    }
+}

VisualStudio/ConfigCommandDescriptor.cs

@@ -5,18 +5,14 @@ namespace VisualStudio
 {
     class ConfigCommandDescriptor : CommandDescriptor
     {
-        readonly VisualStudioOptions options = new VisualStudioOptions(channelVerb: "Open", showNickname: false);
-        bool exp;
+        readonly VisualStudioOptions options = new VisualStudioOptions(channelVerb: "Open", showExp: true, showNickname: false);
 
-        public ConfigCommandDescriptor() => OptionSet = new CompositeOptionSet(options, new OptionSet
-            {
-                { "exp", "Use experimental folder instead of regular.", e => exp = e != null },
-            });
+        public ConfigCommandDescriptor() => OptionSet = new CompositeOptionSet(options);
 
         public Channel? Channel => options.Channel;
 
         public Sku? Sku => options.Sku;
 
-        public bool Experimental => exp;
+        public bool Experimental => options.IsExperimental;
     }
 }

VisualStudio/Program.cs

@@ -1,4 +1,5 @@
 using System;
+using System.IO;
 using System.Linq;
 using System.Threading.Tasks;
 using Mono.Options;
@@ -7,34 +8,52 @@ namespace VisualStudio
 {
     class Program
     {
+        static readonly CommandFactory commandFactory = new CommandFactory();
+
+        TextWriter output;
+        bool execute;
+        string[] args;
+
         static async Task<int> Main(string[] args)
         {
-            var commandFactory = new CommandFactory();
-
             if (args.Length == 0 || new[] { "?", "-?", "/?", "-h", "/h", "--help", "/help" }.Contains(args[0]))
                 return ShowUsage(commandFactory);
 
+            return await new Program(Console.Out, true, args).RunAsync();
+        }
+
+        public Program(TextWriter output, bool execute, params string[] args)
+        {
+            this.output = output;
+            this.execute = execute;
+            this.args = args;
+
             // Run is the default command if another one is not specified.
             if (!commandFactory.IsCommandRegistered(args[0]))
-                args = args.Prepend("run").ToArray();
+                this.args = args.Prepend("run").ToArray();
+        }
 
+        public Command Command { get; private set; }
+
+        public async Task<int> RunAsync()
+        {
             var commandName = args[0];
             try
             {
-                var command = commandFactory.CreateCommand(commandName, args.Skip(1));
+                Command = commandFactory.CreateCommand(commandName, args.Skip(1));
 
-                await command.ExecuteAsync(Console.Out);
-                // TODO: other exceptions might provide an exit code?
+                if (execute)
+                    await Command.ExecuteAsync(output);
             }
             catch (ShowUsageException ex)
             {
-                Console.WriteLine($"Usage: {ThisAssembly.Metadata.AssemblyName} {commandName} [options]");
-                ex.CommandDescriptor.ShowUsage(Console.Out);
+                output.WriteLine($"Usage: {ThisAssembly.Metadata.AssemblyName} {commandName} [options]");
+                ex.CommandDescriptor.ShowUsage(output);
                 return -1;
             }
             catch (OptionException ex)
             {
-                Console.WriteLine(ex.Message);
+                output.WriteLine(ex.Message);
                 return -1;
             }
 

VisualStudio/Properties/launchSettings.json

@@ -2,7 +2,7 @@
   "profiles": {
     "VisualStudio": {
       "commandName": "Project",
-      "commandLineArgs": "kill all exp"
+      "commandLineArgs": "config pre exp"
     }
   }
-}
+}