Check if remote designer is operational

tests/Avalonia.DesignerSupport.Tests/DesignerSupportTests.cs

@@ -11,6 +11,7 @@ using System.Threading;
 using System.Threading.Tasks;
 using Avalonia.Remote.Protocol;
 using Avalonia.Remote.Protocol.Designer;
+using Avalonia.Remote.Protocol.Viewport;
 using Xunit;
 using Xunit.Extensions;
 
@@ -124,5 +125,115 @@ namespace Avalonia.DesignerSupport.Tests
                 proc.WaitForExit();
             }
         }
+        
+        [Theory]
+        [InlineData(
+            @"../../../../../tests/Avalonia.DesignerSupport.TestApp/bin/$BUILD/netcoreapp2.0/",
+            "Avalonia.DesignerSupport.TestApp",
+            "Avalonia.DesignerSupport.TestApp.dll",
+            @"../../../../../tests/Avalonia.DesignerSupport.TestApp/MainWindow.xaml"),
+         InlineData(
+            @"../../../../../samples/ControlCatalog.NetCore/bin/$BUILD/netcoreapp2.0/",
+            "ControlCatalog.NetCore",
+            "ControlCatalog.dll",
+            @"../../../../../samples/ControlCatalog/MainWindow.xaml")]
+        public async Task Designer_Should_Provide_A_Frame(
+            string outputDir,
+            string executableName,
+            string assemblyName,
+            string xamlFile)
+        {
+
+            var xaml = File.ReadAllText(xamlFile);
+            string buildType;
+#if DEBUG
+            buildType = "Debug";
+#else
+            buildType = "Release";
+#endif
+            outputDir = Path.GetFullPath(outputDir.Replace("$BUILD", buildType));
+
+            var sessionId = Guid.NewGuid();
+            FrameMessage receivedFrame = null;
+
+            var resultMessageReceivedToken = new CancellationTokenSource();
+
+            var tcpListener = new TcpListener(IPAddress.Loopback, 0);
+            tcpListener.Start();
+            var port = ((IPEndPoint)tcpListener.LocalEndpoint).Port;
+            tcpListener.Stop();
+            var transport = new BsonTcpTransport();
+            transport.Listen(IPAddress.Loopback, port, conn =>
+            {
+                conn.OnMessage += async (_, msg) =>
+                {
+                    if (msg is StartDesignerSessionMessage start)
+                    {
+                        Assert.Equal(sessionId, Guid.Parse(start.SessionId));
+                        await conn.Send(new ClientSupportedPixelFormatsMessage
+                        {
+                            Formats = new[]
+                            {
+                                Avalonia.Remote.Protocol.Viewport.PixelFormat.Bgra8888,
+                                Avalonia.Remote.Protocol.Viewport.PixelFormat.Rgba8888,
+                            }
+                        });
+                        await conn.Send(new UpdateXamlMessage
+                        {
+                            AssemblyPath = Path.Combine(outputDir, assemblyName),
+                            Xaml = xaml
+                        });
+                    }
+                    else if (msg is UpdateXamlResultMessage result)
+                    {
+                        if (result.Error != null)
+                            outputHelper.WriteLine(result.Error);
+
+                    }
+                    else if (msg is FrameMessage fm)
+                    {
+                        receivedFrame = fm;
+                        resultMessageReceivedToken.Cancel();
+                        conn.Dispose();
+                    }
+                };
+            });
+
+            var cmdline =
+                $"exec --runtimeconfig \"{outputDir}{executableName}.runtimeconfig.json\" --depsfile \"{outputDir}{executableName}.deps.json\" "
+                + $" \"{DesignerAppPath.Replace("$BUILD", buildType)}\" "
+                + $"--transport tcp-bson://127.0.0.1:{port}/ --session-id {sessionId} \"{outputDir}{executableName}.dll\"";
+
+            using (var proc = new Process
+            {
+                StartInfo = new ProcessStartInfo("dotnet", cmdline)
+                {
+                    UseShellExecute = false,
+                    RedirectStandardOutput = true,
+                    RedirectStandardError = true,
+                    CreateNoWindow = true,
+                    WorkingDirectory = outputDir,
+                },
+                EnableRaisingEvents = true
+            })
+            {
+                proc.Start();
+
+                var cancelled = false;
+                try
+                {
+                    await Task.Delay(1000000, resultMessageReceivedToken.Token);
+                }
+                catch (TaskCanceledException)
+                {
+                    cancelled = true;
+                }
+
+                Assert.True(cancelled, $"Message Not Received.");
+                Assert.NotNull(receivedFrame);
+                proc.Kill();
+                proc.WaitForExit();
+            }
+        }
     }
 }