Fix nullability warnings

Gui enhancements - Run selected on enter or double click

.gitignore

@@ -214,3 +214,4 @@ FakesAssemblies/
 **/*.Server/GeneratedArtifacts
 **/*.Server/ModelManifest.xml
 _Pvt_Extensions
+/Settings.XamlStyle

README.md

@@ -3,4 +3,8 @@ XUnit Gui written in WPF
 
 A simple replacement for the old winforms xunit.gui with support for xunit 2.0.
 
+Find it on NuGet at [xunit.runner.wpf](https://www.nuget.org/packages/xunit.runner.wpf).
+
+![Screenshot](docs/screenshot.png)
+
 [![Build status](https://ci.appveyor.com/api/projects/status/13dshnyj592mwe9e/branch/master?svg=true)](https://ci.appveyor.com/project/Pilchie/xunit-runner-wpf/branch/master)

docs/making-a-release.md

@@ -0,0 +1,13 @@
+Steps to make a new release
+===========================
+
+1. Make sure no one else is planning on doing anything that would trigger a build
+2. Check the "next build number" on [AppVeyor](https://ci.appveyor.com/project/Pilchie/xunit-runner-wpf/settings)
+3. Click on [releases](https://github.com/Pilchie/xunit.runner.wpf/releases) -> `Draft a new release`
+4. Set the version to `v1.0.nextbuildnumber` from 2
+5. Set the title to `v1.0.nextbuildnumber - Some reason for the release to exist`
+6. Click `Publish`
+7. This will create the release, and start a new build on AppVeyor
+8. Download the .nupkg from the AppVeyor artifacts page for that new build - (e.g. https://ci.appveyor.com/project/Pilchie/xunit-runner-wpf/build/1.0.15/artifacts)
+9. Go back to the release you created in 6, and add the nupkg, and write a changelog
+10. Tell [@Pilchie](https://github.com/Pilchie) to upload the nupkg to NuGet.org

xunit.runner.data/ClientReader.cs

@@ -7,7 +7,7 @@ namespace Xunit.Runner.Data
     {
         private readonly BinaryReader _reader;
         private bool _closed;
-        private Exception _exception;
+        private Exception? _exception;
 
         public bool IsConnected => !_closed;
 

xunit.runner.data/TestCaseData.cs

@@ -6,13 +6,15 @@ namespace Xunit.Runner.Data
     public sealed class TestCaseData
     {
         public string DisplayName { get; set; }
+        public string UniqueID { get; set; }
         public string SkipReason { get; set; }
         public string AssemblyPath { get; set; }
         public Dictionary<string, List<string>> TraitMap { get; set; }
 
-        public TestCaseData(string displayName, string skipReason, string assemblyPath, Dictionary<string, List<string>> traitMap)
+        public TestCaseData(string displayName, string uniqueID, string skipReason, string assemblyPath, Dictionary<string, List<string>> traitMap)
         {
             DisplayName = displayName;
+            UniqueID = uniqueID;
             SkipReason = skipReason;
             AssemblyPath = assemblyPath;
             TraitMap = traitMap;
@@ -21,6 +23,7 @@ namespace Xunit.Runner.Data
         public static TestCaseData ReadFrom(BinaryReader reader)
         {
             var displayName = reader.ReadString();
+            var uniqueID = reader.ReadString();
             var skipReason = reader.ReadString();
             var assemblyPath = reader.ReadString();
             var count = reader.ReadInt32();
@@ -40,12 +43,13 @@ namespace Xunit.Runner.Data
                 traitMap.Add(key, values);
             }
 
-            return new TestCaseData(displayName, skipReason, assemblyPath, traitMap);
+            return new TestCaseData(displayName, uniqueID, skipReason, assemblyPath, traitMap);
         }
 
         public void WriteTo(BinaryWriter writer)
         {
             writer.Write(DisplayName);
+            writer.Write(UniqueID);
             writer.Write(SkipReason ?? string.Empty);
             writer.Write(AssemblyPath);
             writer.Write(TraitMap.Count);

xunit.runner.data/TestResultData.cs

@@ -10,6 +10,7 @@ namespace Xunit.Runner.Data
     {
         All = 0,
         NotRun,
+        Running,
         Passed,
         Skipped,
         Failed,
@@ -18,12 +19,14 @@ namespace Xunit.Runner.Data
     public sealed class TestResultData
     {
         public string TestCaseDisplayName { get; set; }
+        public string TestCaseUniqueID { get; set; }
         public TestState TestState { get; set; }
         public string Output { get; set; }
 
-        public TestResultData(string displayName, TestState state, string output = "")
+        public TestResultData(string displayName, string uniqueID, TestState state, string output = "")
         {
             TestCaseDisplayName = displayName;
+            TestCaseUniqueID = uniqueID;
             TestState = state;
             Output = output;
         }
@@ -31,14 +34,16 @@ namespace Xunit.Runner.Data
         public static TestResultData ReadFrom(BinaryReader reader)
         {
             var displayName = reader.ReadString();
+            var uniqueID = reader.ReadString();
             var state = (TestState)reader.ReadInt32();
             var output = reader.ReadString();
-            return new TestResultData(displayName, state, output);
+            return new TestResultData(displayName, uniqueID, state, output);
         }
 
         public void WriteTo(BinaryWriter writer)
         {
             writer.Write(TestCaseDisplayName);
+            writer.Write(TestCaseUniqueID);
             writer.Write((int)TestState);
             writer.Write(Output);
         }

xunit.runner.worker/DiscoverUtil.cs

@@ -23,6 +23,7 @@ namespace Xunit.Runner.Worker
                 var testCase = testCaseDiscovered.TestCase;
                 var testCaseData = new TestCaseData(
                     testCase.DisplayName,
+                    testCase.UniqueID,
                     testCase.SkipReason,
                     testCaseDiscovered.TestAssembly.Assembly.AssemblyPath,
                     testCase.Traits);
@@ -34,7 +35,7 @@ namespace Xunit.Runner.Worker
 
         internal static void Go(string assemblyFileName, Stream stream)
         {
-            Go(assemblyFileName, stream, AppDomainSupport.Denied,
+            Go(assemblyFileName, stream, AppDomainSupport.IfAvailable,
                 (xunit, configuration, writer) =>
                 {
                     using (var sink = new TestDiscoverySink(writer))

xunit.runner.worker/MessageSinks/BaseTestRunSink.cs

@@ -19,6 +19,12 @@ namespace Xunit.Runner.Worker.MessageSinks
 
         protected override bool OnMessage(IMessageSinkMessage message)
         {
+            var testStarted = message as ITestStarting;
+            if (testStarted != null)
+            {
+                OnTestStarted(testStarted);
+            }
+
             var testFailed = message as ITestFailed;
             if (testFailed != null)
             {
@@ -47,6 +53,7 @@ namespace Xunit.Runner.Worker.MessageSinks
 
         protected virtual bool ShouldContinue => true;
 
+        protected abstract void OnTestStarted(ITestStarting testStarted);
         protected abstract void OnTestFailed(ITestFailed testFailed);
         protected abstract void OnTestPassed(ITestPassed testPassed);
         protected abstract void OnTestSkipped(ITestSkipped testSkipped);

xunit.runner.worker/Program.cs

@@ -37,8 +37,8 @@ namespace Xunit.Runner.Worker
         {
             Console.WriteLine("xunit.runner.worker [pipe name] [action] [assembly path]");
             Console.WriteLine("\tpipe name:     Name of the pipe this worker should communicate on");
-            Console.WriteLine("\taction:        Action performed by the worker (run or discover tests");
-            Console.WriteLine("\assembly path:  Path of assembly to perform the action against");
+            Console.WriteLine("\taction:        Action performed by the worker (run or discover tests)");
+            Console.WriteLine("\tassembly path:  Path of assembly to perform the action against");
         }
     }
 }

xunit.runner.worker/RunUtil.cs

@@ -21,15 +21,20 @@ namespace Xunit.Runner.Worker
 
             protected override bool ShouldContinue => _writer.IsConnected;
 
-            private void Process(string displayName, TestState state, string output = "")
+            private void Process(string displayName, string uniqueID, TestState state, string output = "")
             {
-                Console.WriteLine($"{state} - {displayName}");
-                var result = new TestResultData(displayName, state, output);
+                System.Diagnostics.Trace.WriteLine($"{state} - {displayName}");
+                var result = new TestResultData(displayName, uniqueID, state, output);
 
                 _writer.Write(TestDataKind.Value);
                 _writer.Write(result);
             }
 
+            protected override void OnTestStarted(ITestStarting testStarted)
+            {
+                Process(testStarted.TestCase.DisplayName, testStarted.TestCase.UniqueID, TestState.Running);
+            }
+
             protected override void OnTestFailed(ITestFailed testFailed)
             {
                 var displayName = testFailed.TestCase.DisplayName;
@@ -46,35 +51,35 @@ namespace Xunit.Runner.Worker
 
                 builder.AppendLine();
 
-                Process(testFailed.TestCase.DisplayName, TestState.Failed, builder.ToString());
+                Process(testFailed.TestCase.DisplayName, testFailed.TestCase.UniqueID, TestState.Failed, builder.ToString());
             }
 
             protected override void OnTestPassed(ITestPassed testPassed)
             {
-                Process(testPassed.TestCase.DisplayName, TestState.Passed);
+                Process(testPassed.TestCase.DisplayName, testPassed.TestCase.UniqueID, TestState.Passed);
             }
 
             protected override void OnTestSkipped(ITestSkipped testSkipped)
             {
-                Process(testSkipped.TestCase.DisplayName, TestState.Skipped);
+                Process(testSkipped.TestCase.DisplayName, testSkipped.TestCase.UniqueID, TestState.Skipped);
             }
         }
 
         private sealed class TestDiscoverySink : BaseTestDiscoverySink
         {
-            private readonly HashSet<string> _testCaseNameSet;
+            private readonly HashSet<string> _testCaseUniqueIDSet;
             private readonly List<ITestCase> _testCaseList;
 
-            internal TestDiscoverySink(HashSet<string> testCaseDisplayNameSet, List<ITestCase> testCaseList)
+            internal TestDiscoverySink(HashSet<string> testCaseUniqueIDSet, List<ITestCase> testCaseList)
             {
-                _testCaseNameSet = testCaseDisplayNameSet;
+                _testCaseUniqueIDSet = testCaseUniqueIDSet;
                 _testCaseList = testCaseList;
             }
 
             protected override void OnTestDiscovered(ITestCaseDiscoveryMessage testCaseDiscovered)
             {
                 var testCase = testCaseDiscovered.TestCase;
-                if (_testCaseNameSet.Contains(testCase.DisplayName))
+                if (_testCaseUniqueIDSet.Contains(testCase.UniqueID))
                 {
                     _testCaseList.Add(testCaseDiscovered.TestCase);
                 }
@@ -82,9 +87,9 @@ namespace Xunit.Runner.Worker
         }
 
         /// <summary>
-        /// Read out the set of test case display names to run.
+        /// Read out the set of test case unique IDs to run.
         /// </summary>
-        private static List<string> ReadTestCaseDisplayNames(Stream stream)
+        private static List<string> ReadTestCaseUniqueIDs(Stream stream)
         {
             using (var reader = new ClientReader(stream))
             {
@@ -133,14 +138,14 @@ namespace Xunit.Runner.Worker
 
         internal static void RunSpecific(string assemblyFileName, Stream stream)
         {
-            var testCaseNameSet = new HashSet<string>(ReadTestCaseDisplayNames(stream), StringComparer.Ordinal);
+            var testCaseUniqueIDSet = new HashSet<string>(ReadTestCaseUniqueIDs(stream), StringComparer.Ordinal);
 
             Go(assemblyFileName, stream, AppDomainSupport.IfAvailable,
                 (xunit, configuration, writer) =>
                 {
                     using (var sink = new TestRunSink(writer))
                     {
-                        var testCaseList = GetTestCaseList(xunit, configuration, testCaseNameSet);
+                        var testCaseList = GetTestCaseList(xunit, configuration, testCaseUniqueIDSet);
 
                         xunit.RunTests(testCaseList, sink,
                             executionOptions: TestFrameworkOptions.ForExecution(configuration));

xunit.runner.worker/xunit.runner.worker.csproj

@@ -13,6 +13,8 @@
     <FileAlignment>512</FileAlignment>
     <AutoGenerateBindingRedirects>true</AutoGenerateBindingRedirects>
     <TargetFrameworkProfile />
+    <NuGetPackageImportStamp>
+    </NuGetPackageImportStamp>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
     <PlatformTarget>AnyCPU</PlatformTarget>

xunit.runner.wpf.sln

@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio 14
-VisualStudioVersion = 14.0.23107.0
+# Visual Studio 15
+VisualStudioVersion = 15.0.26430.4
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "xunit.runner.wpf", "xunit.runner.wpf\xunit.runner.wpf.csproj", "{34FB519C-FB49-4B31-ACA2-7F7879311BCF}"
 EndProject

xunit.runner.wpf/CommandBindings.cs

@@ -16,16 +16,14 @@ namespace Xunit.Runner.Wpf
             }
         }
 
-        public static CommandBindingCollection GetRegistration(UIElement element)
+        public static CommandBindingCollection? GetRegistration(UIElement element)
             => (element != null ? (CommandBindingCollection)element.GetValue(Registration) : null);
 
         private static void OnRegistrationChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
         {
-            UIElement element = sender as UIElement;
-            if (element != null)
+            if (sender is UIElement element)
             {
-                CommandBindingCollection bindings = e.NewValue as CommandBindingCollection;
-                if (bindings != null)
+                if (e.NewValue is CommandBindingCollection bindings)
                 {
                     element.CommandBindings.AddRange(bindings);
                 }

xunit.runner.wpf/Converters/TestStateConverter.cs

@@ -9,6 +9,7 @@ namespace Xunit.Runner.Wpf.Converters
 {
     public class TestStateConverter : IValueConverter
     {
+        private static ImageSource runningSource;
         private static ImageSource failedSource;
         private static ImageSource passedSource;
         private static ImageSource skippedSource;
@@ -17,6 +18,7 @@ namespace Xunit.Runner.Wpf.Converters
 
         static TestStateConverter()
         {
+            runningSource = LoadResourceImage("Running_small.png");
             failedSource = LoadResourceImage("Failed_small.png");
             passedSource = LoadResourceImage("Passed_small.png");
             skippedSource = LoadResourceImage("Skipped_small.png");
@@ -31,13 +33,15 @@ namespace Xunit.Runner.Wpf.Converters
             return image;
         }
 
-        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        public object? Convert(object value, Type targetType, object parameter, CultureInfo culture)
         {
             var state = (TestState)value;
             if (targetType == typeof(Brush))
             {
                 switch (state)
                 {
+                    case TestState.Running:
+                        return Brushes.Blue;
                     case TestState.Failed:
                         return Brushes.Red;
                     case TestState.Passed:
@@ -52,6 +56,8 @@ namespace Xunit.Runner.Wpf.Converters
             {
                 switch (state)
                 {
+                    case TestState.Running:
+                        return runningSource;
                     case TestState.Failed:
                         return failedSource;
                     case TestState.Passed:

xunit.runner.wpf/FilteredCollectionView.cs

@@ -15,6 +15,7 @@ namespace Xunit.Runner.Wpf
         private readonly ObservableCollection<T> dataSource;
         private readonly List<T> filteredList;
         private readonly Func<T, TFilterArg, bool> filter;
+        private readonly IComparer<T> sort;
 
         public FilteredCollectionView(ObservableCollection<T> dataSource, Func<T, TFilterArg, bool> filter, TFilterArg filterArgument, IComparer<T> sort)
         {
@@ -26,6 +27,7 @@ namespace Xunit.Runner.Wpf
             this.filter = filter;
             this.filterArgument = filterArgument;
             this.filteredList = new List<T>();
+            this.sort = sort;
 
             this.dataSource.CollectionChanged += this.dataSource_CollectionChanged;
 
@@ -71,6 +73,7 @@ namespace Xunit.Runner.Wpf
                 }
             }
 
+            this.filteredList.Sort(sort);
             this.OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
         }
 
@@ -115,7 +118,7 @@ namespace Xunit.Runner.Wpf
         {
             if (this.filter(item, this.filterArgument))
             {
-                int index = this.filteredList.IndexOf(item);
+                int index = this.filteredList.BinarySearch(item, sort);
                 if (index < 0)
                 {
                     this.filteredList.Insert(~index, item);
@@ -138,7 +141,7 @@ namespace Xunit.Runner.Wpf
                 observable.PropertyChanged -= this.dataSource_ItemChanged;
             }
 
-            int index = this.filteredList.IndexOf(item);
+            int index = this.filteredList.BinarySearch(item, sort);
             if (index >= 0)
             {
                 this.filteredList.RemoveAt(index);
@@ -149,7 +152,7 @@ namespace Xunit.Runner.Wpf
         private void dataSource_ItemChanged(object sender, PropertyChangedEventArgs e)
         {
             var item = (T)sender;
-            int index = this.filteredList.IndexOf(item);
+            int index = this.filteredList.BinarySearch(item, sort);
             if (this.filter(item, this.FilterArgument))
             {
                 if (index < 0)
@@ -196,7 +199,7 @@ namespace Xunit.Runner.Wpf
             throw new NotSupportedException();
         }
 
-        public bool Contains(T item) => this.filteredList.Contains(item);
+        public bool Contains(T item) => this.filteredList.BinarySearch(item, sort) >= 0;
 
         public void CopyTo(T[] array, int arrayIndex)
         {
@@ -216,7 +219,14 @@ namespace Xunit.Runner.Wpf
 
         IEnumerator IEnumerable.GetEnumerator() => this.GetEnumerator();
 
-        public int IndexOf(T item) => this.filteredList.IndexOf(item);
+        public int IndexOf(T item)
+        {
+            int location = this.filteredList.BinarySearch(item, sort);
+            if (location < 0)
+                return -1;
+
+            return location;
+        }
 
         public void Insert(int index, T item)
         {
@@ -273,7 +283,13 @@ namespace Xunit.Runner.Wpf
 
         object IList.this[int index]
         {
-            get { return this[index]; }
+            get
+            {
+                // Can't figure out how to not get a warning here.
+#pragma warning disable CS8603
+                return this[index];
+#pragma warning restore
+            }
             set { throw new NotSupportedException(); }
         }
 

xunit.runner.wpf/ITestAssemblyWatcher.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+
+namespace Xunit.Runner.Wpf
+{
+    internal interface ITestAssemblyWatcher
+    {
+        /// <summary>
+        /// Adds a new assembly to list of assemblies to be autoreloaded.
+        /// </summary>
+        void AddAssembly(string assemblyFileName);
+
+        /// <summary>
+        /// Removes an assembly from the list of assemblies ot be autoreloaded.
+        /// </summary>
+        void RemoveAssembly(string assemblyFileName);
+
+        /// <summary>
+        /// Enables watching of all assemblies.
+        /// </summary>
+        /// <param name="reloader">Action to perform when a file change is detected</param>
+        void EnableWatch(Func<IEnumerable<string>, bool> reloader);
+
+        /// <summary>
+        /// Disables watching of all assemblies
+        /// </summary>
+        void DisableWatch();
+    }
+}

xunit.runner.wpf/Impl/RemoteTestUtil.BackgroundRunner.cs

@@ -55,13 +55,13 @@ namespace Xunit.Runner.Wpf.Impl
         /// <typeparam name="T"></typeparam>
         private sealed class BackgroundReader<T> where T : class
         {
-            private readonly ConcurrentQueue<T> _queue;
+            private readonly ConcurrentQueue<T?> _queue;
             private readonly ClientReader _reader;
             private readonly Func<ClientReader, T> _readValue;
 
             internal ClientReader Reader => _reader;
 
-            internal BackgroundReader(ConcurrentQueue<T> queue, ClientReader reader, Func<ClientReader, T> readValue)
+            internal BackgroundReader(ConcurrentQueue<T?> queue, ClientReader reader, Func<ClientReader, T> readValue)
             {
                 _queue = queue;
                 _reader = reader;
@@ -111,7 +111,7 @@ namespace Xunit.Runner.Wpf.Impl
             private const int MaxResultPerTick = 1000;
 
             private readonly Connection _connection;
-            private readonly ConcurrentQueue<T> _queue;
+            private readonly ConcurrentQueue<T?> _queue;
             private readonly DispatcherTimer _timer;
             private readonly Action<List<T>> _callback;
             private readonly int _maxPerTick;
@@ -122,7 +122,7 @@ namespace Xunit.Runner.Wpf.Impl
             internal BackgroundProducer(
                 Connection connection, 
                 Dispatcher dispatcher, 
-                ConcurrentQueue<T> queue,
+                ConcurrentQueue<T?> queue,
                 Action<List<T>> callback,
                 int maxResultPerTick = MaxResultPerTick,
                 TimeSpan? interval = null)
@@ -144,8 +144,7 @@ namespace Xunit.Runner.Wpf.Impl
                 var i = 0;
                 var list = new List<T>();
                 var isDone = false;
-                T value;
-                while (i < _maxPerTick && _queue.TryDequeue(out value))
+                while (i < _maxPerTick && _queue.TryDequeue(out T? value))
                 {
                     if (value == null)
                     {

xunit.runner.wpf/Impl/RemoteTestUtil.Connection.cs

@@ -8,10 +8,10 @@ namespace Xunit.Runner.Wpf.Impl
     {
         private sealed class Connection : IDisposable
         {
-            private NamedPipeClientStream _stream;
+            private NamedPipeClientStream? _stream;
             private ClientReader _reader;
 
-            internal NamedPipeClientStream Stream => _stream;
+            internal NamedPipeClientStream Stream => _stream ?? throw new ObjectDisposedException(nameof(Connection));
 
             internal ClientReader Reader => _reader;
 

xunit.runner.wpf/Impl/RemoteTestUtil.cs

@@ -34,14 +34,14 @@ namespace Xunit.Runner.Wpf.Impl
             _processInfo = StartWorkerProcess();
         }
 
-        private async Task<Connection> CreateConnection(string action, string argument)
+        private async Task<Connection> CreateConnection(string action, string argument, CancellationToken cancellationToken)
         {
             var pipeName = GetPipeName();
 
             try
             {
                 var stream = new NamedPipeClientStream(pipeName);
-                await stream.ConnectAsync();
+                await stream.ConnectAsync(cancellationToken);
 
                 var writer = new ClientWriter(stream);
                 writer.Write(action);
@@ -101,7 +101,7 @@ namespace Xunit.Runner.Wpf.Impl
 
         private async Task Discover(string assemblyPath, Action<List<TestCaseData>> callback, CancellationToken cancellationToken)
         {
-            var connection = await CreateConnection(Constants.ActionDiscover, assemblyPath);
+            var connection = await CreateConnection(Constants.ActionDiscover, assemblyPath, cancellationToken);
             await ProcessResultsCore(connection, r => r.ReadTestCaseData(), callback, cancellationToken);
 
             RecycleProcess();
@@ -109,7 +109,7 @@ namespace Xunit.Runner.Wpf.Impl
 
         private async Task RunCore(string actionName, string assemblyPath, ImmutableArray<string> testCaseDisplayNames, Action<List<TestResultData>> callback, CancellationToken cancellationToken)
         {
-            var connection = await CreateConnection(actionName, assemblyPath);
+            var connection = await CreateConnection(actionName, assemblyPath, cancellationToken);
 
             if (!testCaseDisplayNames.IsDefaultOrEmpty)
             {
@@ -123,7 +123,7 @@ namespace Xunit.Runner.Wpf.Impl
         private async Task ProcessResultsCore<T>(Connection connection, Func<ClientReader, T> readValue, Action<List<T>> callback, CancellationToken cancellationToken)
             where T : class
         {
-            var queue = new ConcurrentQueue<T>();
+            var queue = new ConcurrentQueue<T?>();
             var backgroundReader = new BackgroundReader<T>(queue, new ClientReader(connection.Stream), readValue);
             var backgroundProducer = new BackgroundProducer<T>(connection, _dispatcher, queue, callback);
 

xunit.runner.wpf/Impl/TestAssemblyWatcher.cs

@@ -0,0 +1,206 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
+using System.Windows.Threading;
+
+namespace Xunit.Runner.Wpf.Impl
+{
+    internal sealed class TestAssemblyWatcher : ITestAssemblyWatcher
+    {
+        private readonly object sync = new object();
+        private readonly IDictionary<string, FileSystemWatcher> watchedAssemblies = new Dictionary<string, FileSystemWatcher>();
+        private readonly Dispatcher dispatcher;
+        private bool isEnabled = false;
+        private ReloadDebouncer? debouncer;
+
+        public TestAssemblyWatcher(Dispatcher dispatcher)
+        {
+            this.dispatcher = dispatcher;
+        }
+
+        public void AddAssembly(string assemblyFileName)
+        {
+            // Assumptions about adding and removing assemblies are broken if this isn't true
+            Debug.Assert(string.Equals(assemblyFileName, Path.GetFullPath(assemblyFileName), StringComparison.Ordinal));
+
+            lock (sync)
+            {
+                if (watchedAssemblies.ContainsKey(assemblyFileName))
+                {
+                    // Already watching this assembly, nothing to do but return
+                    return;
+                }
+
+                FileSystemWatcher watcher = new FileSystemWatcher
+                {
+                    Path = Path.GetDirectoryName(assemblyFileName),
+                    NotifyFilter = NotifyFilters.CreationTime | NotifyFilters.LastWrite,
+                    Filter = Path.GetFileName(assemblyFileName)
+                };
+
+                watcher.Changed += new FileSystemEventHandler(OnChanged);
+                watcher.Created += new FileSystemEventHandler(OnChanged);
+
+                watchedAssemblies[assemblyFileName] = watcher;
+
+                if (isEnabled)
+                {
+                    watcher.EnableRaisingEvents = true;
+                }
+            }
+        }
+
+        public void RemoveAssembly(string assemblyFileName)
+        {
+            lock (sync)
+            {
+                if (watchedAssemblies.ContainsKey(assemblyFileName))
+                {
+                    watchedAssemblies[assemblyFileName].Dispose();
+                    watchedAssemblies.Remove(assemblyFileName);
+                }
+            }
+        }
+
+        public void EnableWatch(Func<IEnumerable<string>, bool> reloader)
+        {
+            lock (sync)
+            {
+                isEnabled = true;
+
+                foreach (var watcher in watchedAssemblies.Values)
+                {
+                    watcher.EnableRaisingEvents = true;
+                }
+
+                this.debouncer = new ReloadDebouncer(dispatcher, reloader);
+            }
+        }
+
+        public void DisableWatch()
+        {
+            lock (sync)
+            {
+                isEnabled = false;
+
+                foreach (var watcher in watchedAssemblies.Values)
+                {
+                    watcher.EnableRaisingEvents = false;
+                }
+
+                this.debouncer?.Cancel();
+                this.debouncer = null;
+            }
+        }
+
+        private void OnChanged(object source, FileSystemEventArgs args)
+        {
+            debouncer?.AddAssembly(args.FullPath);
+        }
+
+        /// <summary>
+        /// Because, during a build of a number of projects many file system events will be triggered for potentially many
+        /// test assemblies, we need to batch our update requests. This class will do this, waiting for 100 ms after receiving
+        /// a new reload request to send the reload requests. This timer resets every time a reload request is received. Note
+        /// that if you continuously rebuild, this will technicially never finish batching and nothing will reload, but this
+        /// assumes that file events will stop at some point.
+        ///
+        /// If the reloader returns false, meaning that the reload was not kicked off successfully, we back off for a full second
+        /// before reattempting to queue the updates.
+        /// </summary>
+        private class ReloadDebouncer
+        {
+            private readonly object sync = new object();
+            private readonly Dispatcher dispatcher;
+            private readonly Func<IEnumerable<string>, bool> reloader;
+
+            private ISet<string> assembliesToReload = new HashSet<string>();
+            private bool newAssemblyAdded = false;
+            private bool running = false;
+            private bool cancelled = false;
+
+            public ReloadDebouncer(Dispatcher dispatcher, Func<IEnumerable<string>, bool> reloader)
+            {
+                this.dispatcher = dispatcher;
+                this.reloader = reloader;
+            }
+
+            public void AddAssembly(string assembly)
+            {
+                lock (sync)
+                {
+                    assembliesToReload.Add(assembly);
+
+                    if (!Start())
+                    {
+                        newAssemblyAdded = true;
+                    }
+                }
+            }
+
+            public void Cancel()
+            {
+                running = false;
+            }
+
+            private bool Start()
+            {
+                if (running)
+                {
+                    return false;
+                }
+
+                running = true;
+                Task.Run((Action)Debounce);
+                return true;
+            }
+
+            private async void Debounce()
+            {
+                bool backOff = false;
+
+                do
+                {
+                    await Task.Delay(backOff ? 1000 : 100);
+                    backOff = false;
+
+                    lock (sync)
+                    {
+                        void Reset()
+                        {
+                            assembliesToReload = new HashSet<string>();
+                            running = false;
+                        }
+
+                        if (cancelled)
+                        {
+                            Reset();
+                            return;
+                        }
+
+                        // New assemblies added, so we need to wait again
+                        if (newAssemblyAdded)
+                        {
+                            newAssemblyAdded = false;
+                            continue;
+                        }
+
+                        // No new assemblies added, time to alert and exit
+                        if (!dispatcher.Invoke(() => reloader(assembliesToReload)))
+                        {
+                            // If the reloader returned false, it's still busy from the last reload request or other user action.
+                            // Back off for a full second to give it time, then continue as previous
+                            backOff = true;
+                            continue;
+                        }
+                        Reset();
+                    }
+
+                } while (running);
+            }
+        }
+    }
+}

xunit.runner.wpf/MainWindow.xaml

@@ -1,24 +1,25 @@
-<Window x:Class="Xunit.Runner.Wpf.MainWindow"
-        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
-        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
-        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
-        xmlns:local="clr-namespace:Xunit.Runner.Wpf"
-        xmlns:converters="clr-namespace:Xunit.Runner.Wpf.Converters"
-        xmlns:vm="clr-namespace:Xunit.Runner.Wpf.ViewModel"
-        xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
-        xmlns:cmd="clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight.Platform"
-        xmlns:sys="clr-namespace:System;assembly=mscorlib"
-        mc:Ignorable="d"
-        DataContext="{Binding Main, Source={StaticResource Locator}}"
-        Title="xUnit.net Test Runner"
-        Icon="Artwork\Application.ico"
-        ResizeMode="CanResizeWithGrip"
-        Height="600"
-        MinHeight="525"
-        Width="525"
-        MinWidth="425"
-        Name="Main">
+<Window
+    x:Class="Xunit.Runner.Wpf.MainWindow"
+    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:cmd="clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight.Platform"
+    xmlns:converters="clr-namespace:Xunit.Runner.Wpf.Converters"
+    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+    xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
+    xmlns:local="clr-namespace:Xunit.Runner.Wpf"
+    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+    xmlns:sys="clr-namespace:System;assembly=mscorlib"
+    xmlns:vm="clr-namespace:Xunit.Runner.Wpf.ViewModel"
+    Name="Main"
+    Title="xUnit.net Test Runner"
+    Width="525"
+    Height="600"
+    MinWidth="425"
+    MinHeight="525"
+    DataContext="{Binding Main, Source={StaticResource Locator}}"
+    Icon="Artwork\Application.ico"
+    ResizeMode="CanResizeWithGrip"
+    mc:Ignorable="d">
 
     <i:Interaction.Triggers>
         <i:EventTrigger EventName="Loaded">
@@ -43,12 +44,10 @@
 
         <Menu Grid.Row="0">
             <MenuItem Header="_File">
-                <MenuItem Header="E_xit"
-                          Command="{Binding ExitCommand}" />
+                <MenuItem Command="{Binding ExitCommand}" Header="E_xit" />
             </MenuItem>
             <MenuItem Header="_Assembly">
-                <MenuItem Header="_Open"
-                          Command="ApplicationCommands.Open" />
+                <MenuItem Command="ApplicationCommands.Open" Header="_Open" />
                 <MenuItem Header="R_ecent" ItemsSource="{Binding RecentAssemblies}">
                     <MenuItem.ItemContainerStyle>
                         <Style TargetType="MenuItem">
@@ -59,8 +58,14 @@
                     </MenuItem.ItemContainerStyle>
                 </MenuItem>
                 <Separator />
-                <MenuItem Header="_Unload" Command="{Binding AssemblyRemoveAllCommand}"/>
-                <MenuItem Header="_Reload" Command="{Binding AssemblyReloadAllCommand}" />
+                <MenuItem Command="{Binding AssemblyRemoveAllCommand}" Header="_Unload" />
+                <MenuItem Command="{Binding AssemblyReloadAllCommand}" Header="_Reload" />
+                <Separator />
+                <MenuItem
+                    Command="{Binding AutoReloadAssembliesCommand}"
+                    Header="_Auto Reload Test Assemblies"
+                    IsCheckable="True"
+                    IsChecked="{Binding AutoReloadAssemblies}" />
             </MenuItem>
             <MenuItem Header="_Project">
                 <MenuItem Header="_Open" />
@@ -84,10 +89,11 @@
                 <RowDefinition Height="auto" />
             </Grid.RowDefinitions>
 
-            <GroupBox Header="Refinements"
-                      Margin="3"
-                      Grid.Column="0"
-                      Grid.Row="0">
+            <GroupBox
+                Grid.Row="0"
+                Grid.Column="0"
+                Margin="3"
+                Header="Refinements">
                 <Grid>
                     <Grid.RowDefinitions>
                         <RowDefinition Height="auto" />
@@ -98,25 +104,24 @@
                         <RowDefinition Height="*" />
                     </Grid.RowDefinitions>
 
-                    <Label Content="Search:"
-                           Grid.Row="0" />
-                    <TextBox Grid.Row="1"
-                             Text="{Binding FilterString, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
+                    <Label Grid.Row="0" Content="Search:" />
+                    <TextBox Grid.Row="1" Text="{Binding FilterString, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
 
-                    <Label Content="Assemblies:"
-                           Grid.Row="2" />
-                    <ListBox Height="175"
-                             ItemsSource="{Binding Assemblies}"
-                             SelectionMode="Extended"
-                             Grid.Row="3">
+                    <Label Grid.Row="2" Content="Assemblies:" />
+                    <ListBox
+                        Grid.Row="3"
+                        Height="175"
+                        ItemsSource="{Binding Assemblies}"
+                        SelectionMode="Extended">
                         <ListBox.ItemTemplate>
                             <DataTemplate DataType="vm:TestAssemblyViewModel">
                                 <StackPanel Orientation="Horizontal">
                                     <TextBlock Text="{Binding DisplayName}" />
 
-                                    <TextBlock Text=" Discovering tests..."
-                                               FontStyle="Italic"
-                                               Foreground="Gray">
+                                    <TextBlock
+                                        FontStyle="Italic"
+                                        Foreground="Gray"
+                                        Text=" Discovering tests...">
 
                                         <TextBlock.Style>
                                             <Style TargetType="TextBlock">
@@ -136,41 +141,36 @@
 
                         <ListBox.ItemContainerStyle>
                             <Style TargetType="{x:Type ListBoxItem}">
-                                <Setter Property="IsSelected" Value="{Binding Mode=TwoWay, Path=IsSelected}"/>
+                                <Setter Property="IsSelected" Value="{Binding Mode=TwoWay, Path=IsSelected}" />
                             </Style>
                         </ListBox.ItemContainerStyle>
 
                         <ListBox.ContextMenu>
                             <ContextMenu>
-                                <MenuItem Header="Reload" Command="{Binding AssemblyReloadCommand}" />
-                                <MenuItem Header="Reload All" Command="{Binding AssemblyReloadAllCommand}" />
+                                <MenuItem Command="{Binding AssemblyReloadCommand}" Header="Reload" />
+                                <MenuItem Command="{Binding AssemblyReloadAllCommand}" Header="Reload All" />
                                 <Separator />
-                                <MenuItem Header="Remove" Command="{Binding AssemblyRemoveCommand}" />
-                                <MenuItem Header="Remove All" Command="{Binding AssemblyRemoveAllCommand}" />
+                                <MenuItem Command="{Binding AssemblyRemoveCommand}" Header="Remove" />
+                                <MenuItem Command="{Binding AssemblyRemoveAllCommand}" Header="Remove All" />
                             </ContextMenu>
                         </ListBox.ContextMenu>
                     </ListBox>
 
-                    <Label Content="Traits:"
-                           Grid.Row="4" />
+                    <Label Grid.Row="4" Content="Traits:" />
 
-                    <TreeView Grid.Row="5"
-                              ItemsSource="{Binding Traits}">
+                    <TreeView Grid.Row="5" ItemsSource="{Binding Traits}">
 
                         <TreeView.Resources>
-                            <HierarchicalDataTemplate DataType="{x:Type vm:TraitViewModel}"
-                                                      ItemsSource="{Binding Children}">
+                            <HierarchicalDataTemplate DataType="{x:Type vm:TraitViewModel}" ItemsSource="{Binding Children}">
 
-                                <CheckBox IsChecked="{Binding IsChecked}" Content="{Binding Text}" >
+                                <CheckBox Content="{Binding Text}" IsChecked="{Binding IsChecked}">
                                     <i:Interaction.Triggers>
                                         <i:EventTrigger EventName="Checked">
-                                            <cmd:EventToCommand Command="{Binding DataContext.TraitCheckedChangedCommand, RelativeSource={RelativeSource AncestorType=Window}}"
-                                                                CommandParameter="{Binding}" />
+                                            <cmd:EventToCommand Command="{Binding DataContext.TraitCheckedChangedCommand, RelativeSource={RelativeSource AncestorType=Window}}" CommandParameter="{Binding}" />
                                         </i:EventTrigger>
 
                                         <i:EventTrigger EventName="Unchecked">
-                                            <cmd:EventToCommand Command="{Binding DataContext.TraitCheckedChangedCommand, RelativeSource={RelativeSource AncestorType=Window}}"
-                                                                CommandParameter="{Binding}" />
+                                            <cmd:EventToCommand Command="{Binding DataContext.TraitCheckedChangedCommand, RelativeSource={RelativeSource AncestorType=Window}}" CommandParameter="{Binding}" />
                                         </i:EventTrigger>
                                     </i:Interaction.Triggers>
                                 </CheckBox>
@@ -186,7 +186,7 @@
 
                         <TreeView.ContextMenu>
                             <ContextMenu>
-                                <MenuItem Header="Clear" Command="{Binding TraitsClearCommand}" />
+                                <MenuItem Command="{Binding TraitsClearCommand}" Header="Clear" />
                             </ContextMenu>
                         </TreeView.ContextMenu>
 
@@ -194,34 +194,40 @@
                 </Grid>
             </GroupBox>
 
-            <Grid Grid.Column="0"
-                  Grid.Row="1">
+            <Grid Grid.Row="1" Grid.Column="0">
                 <Grid.ColumnDefinitions>
                     <ColumnDefinition Width="*" />
                     <ColumnDefinition Width="*" />
+                    <ColumnDefinition Width="*" />
                 </Grid.ColumnDefinitions>
 
-                <Button Content="_Run All"
-                        Command="{Binding RunCommand}"
-                        Margin="3"
-                        Grid.Column="0" />
-                <Button Content="_Cancel"
-                        Command="{Binding CancelCommand}"
-                        Margin="0,3,3,3"
-                        Grid.Column="1" />
+                <Button
+                    Grid.Column="0"
+                    Margin="10,0,0,0"
+                    Command="{Binding RunAllCommand}"
+                    Content="_Run All" />
+                <Button
+                    Grid.Column="1"
+                    Command="{Binding RunSelectedCommand}"
+                    Content="Run _Selected" />
+                <Button
+                    Grid.Column="2"
+                    Margin="0,0,10,0"
+                    Command="{Binding CancelCommand}"
+                    Content="_Cancel" />
             </Grid>
 
-            <Grid Grid.Column="1"
-                  Grid.Row="0">
+            <Grid Grid.Row="0" Grid.Column="1">
                 <Grid.RowDefinitions>
                     <RowDefinition Height="*" MinHeight="200px" />
                     <RowDefinition Height="auto" />
-                    <RowDefinition Height="*"  MinHeight="200px"/>
+                    <RowDefinition Height="*" MinHeight="200px" />
                 </Grid.RowDefinitions>
 
-                <GroupBox Header="{Binding TestCasesCaption}"
-                          Margin="3"
-                          Grid.Row="0">
+                <GroupBox
+                    Grid.Row="0"
+                    Margin="3"
+                    Header="{Binding TestCasesCaption}">
                     <Grid>
                         <Grid.RowDefinitions>
                             <RowDefinition Height="auto" />
@@ -229,55 +235,82 @@
                         </Grid.RowDefinitions>
 
                         <StackPanel Orientation="Horizontal">
-                            <ToggleButton IsChecked="{Binding FilterPassedTests}"
-                                          BorderThickness="0"
-                                          Background="Transparent"
-                                          Margin="0,4,2,4"
-                                          Grid.Column="0"
-                                          Command="{Binding TestFilterChanged}">
+                            <ToggleButton
+                                Grid.Column="0"
+                                Margin="0,4,2,4"
+                                Background="Transparent"
+                                BorderThickness="0"
+                                Command="{Binding TestFilterChanged}"
+                                IsChecked="{Binding FilterPassedTests}">
                                 <StackPanel Orientation="Horizontal">
                                     <Image Source="Artwork\Passed_large.png" />
-                                    <TextBlock Margin="4,0"
-                                               FontSize="16"
-                                               Text="{Binding TestsPassed, StringFormat={}{0:#\,0}}"
-                                               VerticalAlignment="Center" />
+                                    <TextBlock
+                                        Margin="4,0"
+                                        VerticalAlignment="Center"
+                                        FontSize="16"
+                                        Text="{Binding TestsPassed, StringFormat={}{0:#\,0}}" />
                                 </StackPanel>
                             </ToggleButton>
 
-                            <ToggleButton IsChecked="{Binding FilterFailedTests}"
-                                          BorderThickness="0"
-                                          Background="Transparent"
-                                          Margin="2,4"
-                                          Grid.Column="1"
-                                          Command="{Binding TestFilterChanged}">
+                            <ToggleButton
+                                Grid.Column="1"
+                                Margin="2,4"
+                                Background="Transparent"
+                                BorderThickness="0"
+                                Command="{Binding TestFilterChanged}"
+                                IsChecked="{Binding FilterFailedTests}">
                                 <StackPanel Orientation="Horizontal">
                                     <Image Source="Artwork\Failed_large.png" />
-                                    <TextBlock Margin="4,0"
-                                               FontSize="16"
-                                               Text="{Binding TestsFailed, StringFormat={}{0:#\,0}}" 
-                                               VerticalAlignment="Center" />
+                                    <TextBlock
+                                        Margin="4,0"
+                                        VerticalAlignment="Center"
+                                        FontSize="16"
+                                        Text="{Binding TestsFailed, StringFormat={}{0:#\,0}}" />
                                 </StackPanel>
                             </ToggleButton>
 
-                            <ToggleButton IsChecked="{Binding FilterSkippedTests}"
-                                          BorderThickness="0"
-                                          Background="Transparent"
-                                          Margin="2,4,0,4"
-                                          Grid.Column="2"
-                                          Command="{Binding TestFilterChanged}">
+                            <ToggleButton
+                                Grid.Column="2"
+                                Margin="2,4,0,4"
+                                Background="Transparent"
+                                BorderThickness="0"
+                                Command="{Binding TestFilterChanged}"
+                                IsChecked="{Binding FilterSkippedTests}">
                                 <StackPanel Orientation="Horizontal">
                                     <Image Source="Artwork\Skipped_large.png" />
-                                    <TextBlock Margin="4,0"
-                                               FontSize="16"
-                                               Text="{Binding TestsSkipped, StringFormat={}{0:#\,0}}" 
-                                               VerticalAlignment="Center" />
+                                    <TextBlock
+                                        Margin="4,0"
+                                        VerticalAlignment="Center"
+                                        FontSize="16"
+                                        Text="{Binding TestsSkipped, StringFormat={}{0:#\,0}}" />
+                                </StackPanel>
+                            </ToggleButton>
+
+                            <ToggleButton
+                                Grid.Column="2"
+                                Margin="2,4,0,4"
+                                Background="Transparent"
+                                BorderThickness="0"
+                                Command="{Binding TestFilterChanged}"
+                                IsChecked="{Binding FilterRunningTests}">
+                                <StackPanel Orientation="Horizontal">
+                                    <Image Source="Artwork\Running_large.png" />
+                                    <TextBlock
+                                        Margin="4,0"
+                                        VerticalAlignment="Center"
+                                        FontSize="16"
+                                        Text="{Binding TestsRunning, StringFormat={}{0:#\,0}}" />
                                 </StackPanel>
                             </ToggleButton>
                         </StackPanel>
 
-                        <ListBox ItemsSource="{Binding FilteredTestCases}"
-                                 SelectionMode="Extended"
-                                 Grid.Row="1">
+                        <ListBox
+                            x:Name="TestCases"
+                            Grid.Row="1"
+                            ItemsSource="{Binding FilteredTestCases}"
+                            SelectedItem="{Binding SelectedTestCase, Mode=TwoWay}"
+                            SelectionChanged="TestCases_SelectionChanged"
+                            SelectionMode="Extended">
                             <ListBox.ItemTemplate>
                                 <DataTemplate DataType="vm:TestCaseViewModel">
                                     <Grid>
@@ -286,49 +319,71 @@
                                             <ColumnDefinition Width="*" />
                                         </Grid.ColumnDefinitions>
 
-                                        <Image Width="16"
-                                               Margin="0,0,2,0"
-                                               Source="{Binding Path=State, Mode=OneWay, Converter={StaticResource TestStateConverter}}"
-                                               Grid.Column="0" />
+                                        <Image
+                                            Grid.Column="0"
+                                            Width="16"
+                                            Margin="0,0,2,0"
+                                            Source="{Binding Path=State, Mode=OneWay, Converter={StaticResource TestStateConverter}}" />
 
-                                        <TextBlock Text="{Binding DisplayName}"
-                                                   VerticalAlignment="Center"
-                                                   Grid.Column="1" />
+                                        <TextBlock
+                                            Grid.Column="1"
+                                            VerticalAlignment="Center"
+                                            Text="{Binding DisplayName}" />
                                     </Grid>
                                 </DataTemplate>
                             </ListBox.ItemTemplate>
+                            <ListBox.InputBindings>
+                                <KeyBinding Key="Enter" Command="{Binding RunSelectedCommand}" />
+                            </ListBox.InputBindings>
+                            <i:Interaction.Triggers>
+                                <i:EventTrigger EventName="MouseDoubleClick">
+                                    <cmd:EventToCommand Command="{Binding Path=RunSelectedCommand}" PassEventArgsToCommand="False" />
+                                </i:EventTrigger>
+                            </i:Interaction.Triggers>
                         </ListBox>
                     </Grid>
                 </GroupBox>
 
-                <GridSplitter Grid.Row="1" HorizontalAlignment="Stretch" Height="3" Background="White"/>
+                <GridSplitter
+                    Grid.Row="1"
+                    Height="3"
+                    HorizontalAlignment="Stretch"
+                    Background="White" />
 
-                <GroupBox Header="Output"
-                          Margin="3"
-                          Grid.Row="2">
-                    <TextBox IsReadOnly="True"
-                             HorizontalScrollBarVisibility="Auto"
-                             VerticalScrollBarVisibility="Visible"
-                             FontFamily="Consolas"
-                             Text="{Binding Output}"/>
+                <GroupBox
+                    Grid.Row="2"
+                    Margin="3"
+                    Header="Output">
+                    <TextBox
+                        FontFamily="Consolas"
+                        HorizontalScrollBarVisibility="Auto"
+                        IsReadOnly="True"
+                        Text="{Binding Output}"
+                        VerticalScrollBarVisibility="Visible" />
                 </GroupBox>
             </Grid>
-            
-            <GridSplitter Grid.Column="0" VerticalAlignment="Stretch" Width="3" Background="White"/>
-            
-            <ProgressBar Foreground="{Binding Path=CurrentRunState, Converter={StaticResource TestStateConverter}, Mode=OneWay}"
-                         Minimum="0"
-                         Maximum="{Binding MaximumProgress}"
-                         Value="{Binding Path=TestsCompleted}"
-                         Grid.Column="1"
-                         Grid.Row="1"
-                         Margin="3" />
+
+            <GridSplitter
+                Grid.Column="0"
+                Width="3"
+                VerticalAlignment="Stretch"
+                Background="White" />
+
+            <ProgressBar
+                Grid.Row="1"
+                Grid.Column="1"
+                Margin="3"
+                Foreground="{Binding Path=CurrentRunState, Converter={StaticResource TestStateConverter}, Mode=OneWay}"
+                Maximum="{Binding MaximumProgress}"
+                Minimum="0"
+                Value="{Binding Path=TestsCompleted}" />
         </Grid>
 
         <StackPanel Grid.Row="2">
-            <Border BorderBrush="LightGray"
-                    BorderThickness="1"
-                    Margin="3" />
+            <Border
+                Margin="3"
+                BorderBrush="LightGray"
+                BorderThickness="1" />
             <StatusBar>
                 <StatusBar.ItemsPanel>
                     <ItemsPanelTemplate>
@@ -338,7 +393,7 @@
                                 <ColumnDefinition Width="auto" />
                                 <ColumnDefinition Width="auto" />
                                 <ColumnDefinition Width="auto" />
-                                <ColumnDefinition Width="16"/>
+                                <ColumnDefinition Width="16" />
                             </Grid.ColumnDefinitions>
                         </Grid>
                     </ItemsPanelTemplate>
@@ -346,28 +401,25 @@
 
                 <StatusBarItem Grid.Column="1">
                     <StackPanel Orientation="Horizontal">
-                        <TextBlock Text="Tests passed: "
-                                   Foreground="DarkGreen"/>
+                        <TextBlock Foreground="DarkGreen" Text="Tests passed: " />
 
-                        <TextBlock Text="{Binding TestsPassed, StringFormat={}{0:#\,0}}"/>
+                        <TextBlock Text="{Binding TestsPassed, StringFormat={}{0:#\,0}}" />
                     </StackPanel>
                 </StatusBarItem>
 
                 <StatusBarItem Grid.Column="2">
                     <StackPanel Orientation="Horizontal">
-                        <TextBlock Text="Tests failed: "
-                                   Foreground="DarkRed"/>
+                        <TextBlock Foreground="DarkRed" Text="Tests failed: " />
 
-                        <TextBlock Text="{Binding TestsFailed, StringFormat={}{0:#\,0}}"/>
+                        <TextBlock Text="{Binding TestsFailed, StringFormat={}{0:#\,0}}" />
                     </StackPanel>
                 </StatusBarItem>
 
                 <StatusBarItem Grid.Column="3">
                     <StackPanel Orientation="Horizontal">
-                        <TextBlock Text="Tests skipped: "
-                                   Foreground="DarkGoldenrod"/>
+                        <TextBlock Foreground="DarkGoldenrod" Text="Tests skipped: " />
 
-                        <TextBlock Text="{Binding TestsSkipped, StringFormat={}{0:#\,0}}"/>
+                        <TextBlock Text="{Binding TestsSkipped, StringFormat={}{0:#\,0}}" />
                     </StackPanel>
                 </StatusBarItem>
             </StatusBar>

xunit.runner.wpf/MainWindow.xaml.cs

@@ -5,16 +5,21 @@ using Xunit.Runner.Wpf.Persistence;
 
 namespace Xunit.Runner.Wpf
 {
+    using ViewModel;
+
     public partial class MainWindow : Window
     {
         public static Window Instance { get; private set; }
 
+        // WPF generates fields that are marked as non-nullable, but not definitely initialized.
+#pragma warning disable CS8618
         public MainWindow()
         {
             Instance = this;
 
             InitializeComponent();
         }
+#pragma warning restore
 
         protected override void OnSourceInitialized(EventArgs e)
         {
@@ -29,5 +34,26 @@ namespace Xunit.Runner.Wpf
 
             base.OnClosing(e);
         }
+
+        private void TestCases_SelectionChanged(Object sender, System.Windows.Controls.SelectionChangedEventArgs e)
+        {
+            foreach (var item in e.AddedItems)
+            {
+                var model = item as TestCaseViewModel;
+                if (model != null)
+                {
+                    model.IsSelected = true;
+                }
+            }
+
+            foreach (var item in e.RemovedItems)
+            {
+                var model = item as TestCaseViewModel;
+                if (model != null)
+                {
+                    model.IsSelected = false;
+                }
+            }
+        }
     }
 }

xunit.runner.wpf/Persistence/Settings.cs

@@ -14,21 +14,24 @@ namespace Xunit.Runner.Wpf.Persistence
         private const string RecentAssemblyElementName = "recent_assembly";
         private const string SettingsElementName = "settings";
         private const string VersionAttributeName = "version";
+        private const string AutoReloadAssembliesElementName = "auto_reload_assemblies";
 
         private const int MaxRecentAssemblies = 10;
 
         private static readonly Version s_latestVersion = new Version(1, 0, 0, 0);
 
         private List<string> recentAssemblies;
+        private bool autoReloadAssemblies;
 
         private Settings()
         {
             recentAssemblies = new List<string>();
+            autoReloadAssemblies = true;
         }
 
         public void AddRecentAssembly(string filePath)
         {
-            for (int i = recentAssemblies.Count - 1; i > 0; i--)
+            for (int i = recentAssemblies.Count - 1; i >= 0; i--)
             {
                 if (StringComparer.OrdinalIgnoreCase.Equals(recentAssemblies[i], filePath))
                 {
@@ -44,6 +47,13 @@ namespace Xunit.Runner.Wpf.Persistence
             }
         }
 
+        public void ToggleAutoReloadAssemblies()
+        {
+            autoReloadAssemblies = !autoReloadAssemblies;
+        }
+
+        public bool GetAutoReloadAssemblies() => autoReloadAssemblies;
+
         public ImmutableArray<string> GetRecentAssemblies()
         {
             return this.recentAssemblies.ToImmutableArray();
@@ -66,6 +76,8 @@ namespace Xunit.Runner.Wpf.Persistence
                     xml.Add(recentAssembliesElement);
                 }
 
+                xml.Add(new XElement(AutoReloadAssembliesElementName, autoReloadAssemblies));
+
                 xml.Save(xmlFile);
             }
         }
@@ -103,6 +115,21 @@ namespace Xunit.Runner.Wpf.Persistence
                     }
                 }
 
+                var autoReloadAssembliesElement = xml.Element(AutoReloadAssembliesElementName);
+                if (autoReloadAssembliesElement != null)
+                {
+                    if (!bool.TryParse(autoReloadAssembliesElement.Value, out var autoReloadAssemblies))
+                    {
+                        autoReloadAssemblies = true;
+                    }
+
+                    settings.autoReloadAssemblies = autoReloadAssemblies;
+                }
+                else
+                {
+                    settings.autoReloadAssemblies = true;
+                }
+
                 return settings;
             }
         }

xunit.runner.wpf/Persistence/Storage.cs

@@ -16,7 +16,7 @@ namespace Xunit.Runner.Wpf.Persistence
 
         private static IsolatedStorageFile GetStorageFile() => IsolatedStorageFile.GetUserStoreForDomain();
 
-        public static XmlTextReader OpenXmlFile(string fileName)
+        public static XmlTextReader? OpenXmlFile(string fileName)
         {
             var storage = GetStorageFile();
             if (!storage.FileExists(fileName))

xunit.runner.wpf/ViewModel/AssemblyAndConfigFile.cs

@@ -5,9 +5,9 @@ namespace Xunit.Runner.Wpf.ViewModel
     public class AssemblyAndConfigFile
     {
         public string AssemblyFileName { get; }
-        public string ConfigFileName { get; }
+        public string? ConfigFileName { get; }
 
-        public AssemblyAndConfigFile(string assemblyFileName, string configFileName)
+        public AssemblyAndConfigFile(string assemblyFileName, string? configFileName)
         {
             this.AssemblyFileName = Path.GetFullPath(assemblyFileName);
             if (configFileName != null)

xunit.runner.wpf/ViewModel/MainViewModel.cs

@@ -25,34 +25,50 @@ namespace Xunit.Runner.Wpf.ViewModel
         private readonly Settings settings;
 
         private readonly ITestUtil testUtil;
+        private readonly ITestAssemblyWatcher assemblyWatcher;
+        private readonly HashSet<string> allTestCaseUniqueIDs = new HashSet<string>();
         private readonly ObservableCollection<TestCaseViewModel> allTestCases = new ObservableCollection<TestCaseViewModel>();
         private readonly TraitCollectionView traitCollectionView = new TraitCollectionView();
+        private readonly HashSet<string> runningTestSet = new HashSet<string>();
+
         private CancellationTokenSource filterCancellationTokenSource = new CancellationTokenSource();
 
-        private CancellationTokenSource cancellationTokenSource;
+        private CancellationTokenSource? cancellationTokenSource;
         private bool isBusy;
         private SearchQuery searchQuery = new SearchQuery();
+        private bool autoReloadAssemblies;
 
         public ObservableCollection<TestAssemblyViewModel> Assemblies { get; } = new ObservableCollection<TestAssemblyViewModel>();
         public FilteredCollectionView<TestCaseViewModel, SearchQuery> FilteredTestCases { get; }
         public ObservableCollection<TraitViewModel> Traits => this.traitCollectionView.Collection;
+        public bool AutoReloadAssemblies
+        {
+            get => autoReloadAssemblies;
+            set
+            {
+                var oldVal = autoReloadAssemblies;
+                autoReloadAssemblies = value;
+                RaisePropertyChanged(nameof(AutoReloadAssemblies), oldVal, autoReloadAssemblies);
+            }
+        }
 
         public ObservableCollection<RecentAssemblyViewModel> RecentAssemblies { get; } = new ObservableCollection<RecentAssemblyViewModel>();
 
-        private ImmutableList<TestCaseViewModel> runningTests;
+        private ImmutableList<TestCaseViewModel>? testsToRun;
 
         public ICommand ExitCommand { get; }
         public ICommand WindowLoadedCommand { get; }
         public RelayCommand<CancelEventArgs> WindowClosingCommand { get; }
-        public RelayCommand RunCommand { get; }
+        public RelayCommand RunAllCommand { get; }
+        public RelayCommand RunSelectedCommand { get; }
         public RelayCommand CancelCommand { get; }
         public ICommand TraitCheckedChangedCommand { get; }
-        public ICommand TraitSelectionChangedCommand { get; }
         public ICommand TraitsClearCommand { get; }
         public ICommand AssemblyReloadCommand { get; }
         public ICommand AssemblyReloadAllCommand { get; }
         public ICommand AssemblyRemoveCommand { get; }
         public ICommand AssemblyRemoveAllCommand { get; }
+        public ICommand AutoReloadAssembliesCommand { get; }
 
         public CommandBindingCollection CommandBindings { get; }
 
@@ -68,6 +84,7 @@ namespace Xunit.Runner.Wpf.ViewModel
             CommandBindings = CreateCommandBindings();
 
             this.testUtil = new Xunit.Runner.Wpf.Impl.RemoteTestUtil(Dispatcher.CurrentDispatcher);
+            this.assemblyWatcher = new Impl.TestAssemblyWatcher(Dispatcher.CurrentDispatcher);
             this.TestCasesCaption = "Test Cases (0)";
 
             this.FilteredTestCases = new FilteredCollectionView<TestCaseViewModel, SearchQuery>(
@@ -78,7 +95,8 @@ namespace Xunit.Runner.Wpf.ViewModel
             this.ExitCommand = new RelayCommand(OnExecuteExit);
             this.WindowLoadedCommand = new RelayCommand(OnExecuteWindowLoaded);
             this.WindowClosingCommand = new RelayCommand<CancelEventArgs>(OnExecuteWindowClosing);
-            this.RunCommand = new RelayCommand(OnExecuteRun, CanExecuteRun);
+            this.RunAllCommand = new RelayCommand(OnExecuteRunAll, CanExecuteRunAll);
+            this.RunSelectedCommand = new RelayCommand(OnExecuteRunSelected, CanExecuteRunSelected);
             this.CancelCommand = new RelayCommand(OnExecuteCancel, CanExecuteCancel);
             this.TraitCheckedChangedCommand = new RelayCommand<TraitViewModel>(OnExecuteTraitCheckedChanged);
             this.TraitsClearCommand = new RelayCommand(OnExecuteTraitsClear);
@@ -86,8 +104,11 @@ namespace Xunit.Runner.Wpf.ViewModel
             this.AssemblyReloadAllCommand = new RelayCommand(OnExecuteAssemblyReloadAll);
             this.AssemblyRemoveCommand = new RelayCommand(OnExecuteAssemblyRemove, CanExecuteAssemblyRemove);
             this.AssemblyRemoveAllCommand = new RelayCommand(OnExecuteAssemblyRemoveAll);
+            this.AutoReloadAssembliesCommand = new RelayCommand(OnToggleAutoReloadAssemblies);
 
             RebuildRecentAssembliesMenu();
+            AutoReloadAssemblies = this.settings.GetAutoReloadAssemblies();
+            UpdateAutoReloadStatus();
         }
 
         private void RebuildRecentAssembliesMenu()
@@ -133,10 +154,13 @@ namespace Xunit.Runner.Wpf.ViewModel
                 }
             }
 
-            var noFilter = !(searchQuery.FilterFailedTests | searchQuery.FilterPassedTests | searchQuery.FilterSkippedTests);
+            var noFilter = !(searchQuery.FilterRunningTests | searchQuery.FilterFailedTests | searchQuery.FilterPassedTests | searchQuery.FilterSkippedTests);
 
             switch (testCase.State)
             {
+                case TestState.Running:
+                    return noFilter || searchQuery.FilterRunningTests;
+
                 case TestState.Passed:
                     return noFilter || searchQuery.FilterPassedTests;
 
@@ -157,8 +181,32 @@ namespace Xunit.Runner.Wpf.ViewModel
 
         private void TestCases_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
         {
-            TestCasesCaption = $"Test Cases ({FilteredTestCases.Count:#,0})";
-            MaximumProgress = FilteredTestCases.Count;
+            UpdateTestCaseInfo(useSelected: false);
+            ClearSelectionFlags();
+        }
+
+        private void ClearSelectionFlags()
+        {
+            foreach (var test in this.allTestCases)
+            {
+                test.IsSelected = false;
+            }
+        }
+
+        void UpdateTestCaseInfo(bool useSelected)
+        {
+            var count = FilteredTestCases.Count;
+            if (useSelected)
+            {
+                var selected = FilteredTestCases.Count(tc => tc.IsSelected);
+                if (selected > 0)
+                {
+                    count = selected;
+                }
+            }
+
+            TestCasesCaption = $"Test Cases ({count:#,0})";
+            MaximumProgress = count;
         }
 
         public List<TestAssemblyViewModel> SelectedAssemblies
@@ -166,8 +214,8 @@ namespace Xunit.Runner.Wpf.ViewModel
             get { return Assemblies.Where(x => x.IsSelected).ToList(); }
         }
 
-        private string testCasesCaption;
-        public string TestCasesCaption
+        private string? testCasesCaption;
+        public string? TestCasesCaption
         {
             get { return testCasesCaption; }
             private set { Set(ref testCasesCaption, value); }
@@ -177,14 +225,32 @@ namespace Xunit.Runner.Wpf.ViewModel
         public int TestsCompleted
         {
             get { return testsCompleted; }
-            set { Set(ref testsCompleted, value);
 
-                if (TaskbarManager.IsPlatformSupported)
-                {
-                    var tb = TaskbarManager.Instance;
-                    tb.SetProgressState(GetTaskBarState());
-                    tb.SetProgressValue(value, this.MaximumProgress);
-                }
+            set
+            {
+                Set(ref testsCompleted, value);
+                UpdateProgress();
+            }
+        }
+
+        private TestCaseViewModel? selectedTest;
+        public TestCaseViewModel? SelectedTestCase
+        {
+            get { return selectedTest; }
+
+            set
+            {
+                Set(ref selectedTest, value);
+            }
+        }
+
+        private void UpdateProgress()
+        {
+            if (TaskbarManager.IsPlatformSupported)
+            {
+                var tb = TaskbarManager.Instance;
+                tb.SetProgressState(GetTaskBarState());
+                tb.SetProgressValue(this.TestsCompleted, this.MaximumProgress);
             }
         }
 
@@ -201,6 +267,13 @@ namespace Xunit.Runner.Wpf.ViewModel
             }
         }
 
+        private int testsRunning = 0;
+        public int TestsRunning
+        {
+            get { return testsRunning; }
+            set { Set(ref testsRunning, value); }
+        }
+
         private int testsPassed = 0;
         public int TestsPassed
         {
@@ -226,14 +299,24 @@ namespace Xunit.Runner.Wpf.ViewModel
         public int MaximumProgress
         {
             get { return maximumProgress; }
-            set { Set(ref maximumProgress, value); }
+
+            set
+            {
+                Set(ref maximumProgress, value);
+                UpdateProgress();
+            }
         }
 
         private TestState currentRunState;
         public TestState CurrentRunState
         {
             get { return currentRunState; }
-            set { Set(ref currentRunState, value); }
+
+            set
+            {
+                Set(ref currentRunState, value);
+                UpdateProgress();
+            }
         }
 
         private string output = string.Empty;
@@ -317,7 +400,7 @@ namespace Xunit.Runner.Wpf.ViewModel
                     var taskList = new List<Task>();
                     foreach (var assembly in assemblies)
                     {
-                        taskList.Add(this.testUtil.Discover(assembly.AssemblyFileName, this.OnTestsDiscovered, this.cancellationTokenSource.Token));
+                        taskList.Add(this.testUtil.Discover(assembly.AssemblyFileName, this.OnTestsDiscovered, CancellationToken));
 
                         var assemblyViewModel = new TestAssemblyViewModel(assembly);
 
@@ -336,12 +419,31 @@ namespace Xunit.Runner.Wpf.ViewModel
                 foreach (var assemblyViewModel in newAssemblyViewModels)
                 {
                     assemblyViewModel.State = AssemblyState.Ready;
+                    assemblyWatcher.AddAssembly(assemblyViewModel.FileName);
                 }
 
                 RebuildRecentAssembliesMenu();
             }
         }
 
+        private CancellationToken CancellationToken
+            => cancellationTokenSource == null
+                ? CancellationToken.None
+                : cancellationTokenSource.Token;
+
+        public bool ReloadAssemblies(IEnumerable<string> assemblies)
+        {
+            if (IsBusy)
+            {
+                return false;
+            }
+
+            var testAssemblies = Assemblies.Where(assembly => assemblies.Contains(assembly.FileName));
+            Application.Current.Dispatcher.InvokeAsync(() => ReloadAssemblies(testAssemblies));
+
+            return true;
+        }
+
         private async Task ReloadAssemblies(IEnumerable<TestAssemblyViewModel> assemblies)
         {
             try
@@ -356,7 +458,7 @@ namespace Xunit.Runner.Wpf.ViewModel
                         var assemblyFileName = assemblyViewModel.FileName;
                         RemoveAssemblyTestCases(assemblyFileName);
 
-                        taskList.Add(this.testUtil.Discover(assemblyFileName, OnTestsDiscovered, cancellationTokenSource.Token));
+                        taskList.Add(this.testUtil.Discover(assemblyFileName, OnTestsDiscovered, CancellationToken));
                     }
 
                     return taskList;
@@ -377,6 +479,7 @@ namespace Xunit.Runner.Wpf.ViewModel
         {
             foreach (var assembly in assemblies.ToList())
             {
+                assemblyWatcher.RemoveAssembly(assembly.FileName);
                 RemoveAssemblyTestCases(assembly.FileName);
                 Assemblies.Remove(assembly);
             }
@@ -391,6 +494,7 @@ namespace Xunit.Runner.Wpf.ViewModel
             {
                 if (string.Compare(this.allTestCases[i].AssemblyFileName, assemblyPath, StringComparison.OrdinalIgnoreCase) == 0)
                 {
+                    this.allTestCaseUniqueIDs.Remove(this.allTestCases[i].UniqueID);
                     this.allTestCases.RemoveAt(i);
                 }
                 else
@@ -401,10 +505,10 @@ namespace Xunit.Runner.Wpf.ViewModel
         }
 
         /// <summary>
-        /// Reloading an assembly could have changed the traits.  There is no easy way 
-        /// to selectively edit this list (traits can cross assembly boundaries).  Just 
+        /// Reloading an assembly could have changed the traits.  There is no easy way
+        /// to selectively edit this list (traits can cross assembly boundaries).  Just
         /// do a full reload instead.
-        /// way to 
+        /// way to
         /// </summary>
         private void RebuildTraits()
         {
@@ -421,7 +525,8 @@ namespace Xunit.Runner.Wpf.ViewModel
             set
             {
                 isBusy = value;
-                RunCommand.RaiseCanExecuteChanged();
+                RunAllCommand.RaiseCanExecuteChanged();
+                RunSelectedCommand.RaiseCanExecuteChanged();
                 CancelCommand.RaiseCanExecuteChanged();
             }
         }
@@ -448,7 +553,7 @@ namespace Xunit.Runner.Wpf.ViewModel
                 var assemblyFileName = enumerable.First();
                 enumerable = enumerable.Skip(1);
 
-                var configFileName = (string)null;
+                var configFileName = (string?)null;
                 if (IsConfigFile(enumerable.FirstOrDefault()))
                 {
                     configFileName = enumerable.First();
@@ -463,61 +568,87 @@ namespace Xunit.Runner.Wpf.ViewModel
             => (fileName?.EndsWith(".config", StringComparison.OrdinalIgnoreCase) ?? false) ||
                (fileName?.EndsWith(".json", StringComparison.OrdinalIgnoreCase) ?? false);
 
-        private bool CanExecuteRun()
+        private bool CanExecuteRunAll()
             => !IsBusy && FilteredTestCases.Any();
 
-        private async void OnExecuteRun()
+        private bool CanExecuteRunSelected()
+            => !IsBusy && SelectedTestCase != null;
+
+        private async void OnExecuteRunAll()
         {
-            Debug.Assert(this.runningTests == null);
+            Debug.Assert(this.testsToRun == null);
+            UpdateTestCaseInfo(useSelected: false);
 
-            await ExecuteTestSessionOperation(RunTests);
+            await ExecuteTestSessionOperation(RunFilteredTests);
 
-            this.runningTests = null;
+            this.testsToRun = null;
         }
 
-        private List<Task> RunTests()
+        private List<Task> RunFilteredTests()
+        {
+            return RunTests(FilteredTestCases.ToImmutableList());
+        }
+
+        private async void OnExecuteRunSelected()
+        {
+            Debug.Assert(this.testsToRun == null);
+            Debug.Assert(this.SelectedTestCase != null);
+            UpdateTestCaseInfo(useSelected: true);
+
+            await ExecuteTestSessionOperation(RunSelectedTests);
+
+            this.testsToRun = null;
+        }
+
+        private List<Task> RunSelectedTests()
+        {
+            return RunTests(ImmutableList.CreateRange(this.FilteredTestCases.Where(tc => tc.IsSelected)));
+        }
+
+        private List<Task> RunTests(ImmutableList<TestCaseViewModel> tests)
         {
             Debug.Assert(this.isBusy);
             Debug.Assert(this.cancellationTokenSource != null);
-            Debug.Assert(this.runningTests == null);
+            Debug.Assert(this.testsToRun == null);
 
             TestsCompleted = 0;
+            TestsRunning = 0;
             TestsPassed = 0;
             TestsFailed = 0;
             TestsSkipped = 0;
             CurrentRunState = TestState.NotRun;
             Output = string.Empty;
 
-            this.runningTests = FilteredTestCases.ToImmutableList();
+            this.testsToRun = tests;
 
-            foreach (var tc in this.runningTests)
+            foreach (var tc in this.testsToRun)
             {
                 tc.State = TestState.NotRun;
             }
 
-            var runAll = this.runningTests.Count == this.allTestCases.Count;
+            var runAll = this.testsToRun.Count == this.allTestCases.Count;
             var testSessionList = new List<Task>();
 
-            foreach (var assemblyFileName in this.runningTests.Select(x => x.AssemblyFileName).Distinct())
+            foreach (var assemblyFileName in this.testsToRun.Select(x => x.AssemblyFileName).Distinct())
             {
                 Task task;
                 if (runAll)
                 {
-                    task = this.testUtil.RunAll(assemblyFileName, OnTestsFinished, this.cancellationTokenSource.Token);
+                    task = this.testUtil.RunAll(assemblyFileName, OnTestStateChange, CancellationToken);
                 }
                 else
                 {
                     var builder = ImmutableArray.CreateBuilder<string>();
 
-                    foreach (var testCase in this.runningTests)
+                    foreach (var testCase in this.testsToRun)
                     {
                         if (testCase.AssemblyFileName == assemblyFileName)
                         {
-                            builder.Add(testCase.DisplayName);
+                            builder.Add(testCase.UniqueID);
                         }
                     }
 
-                    task = this.testUtil.RunSpecific(assemblyFileName, builder.ToImmutable(), OnTestsFinished, this.cancellationTokenSource.Token);
+                    task = this.testUtil.RunSpecific(assemblyFileName, builder.ToImmutable(), OnTestStateChange, CancellationToken);
                 }
 
                 testSessionList.Add(task);
@@ -557,6 +688,9 @@ namespace Xunit.Runner.Wpf.ViewModel
 
             foreach (var testCase in testCases)
             {
+                if (this.allTestCaseUniqueIDs.Contains(testCase.UniqueID))
+                    continue;
+
                 traitWorkerList.Clear();
 
                 // Get or create traits.
@@ -579,6 +713,7 @@ namespace Xunit.Runner.Wpf.ViewModel
 
                 var testCaseViewModel = new TestCaseViewModel(
                     testCase.DisplayName,
+                    testCase.UniqueID,
                     testCase.SkipReason,
                     testCase.AssemblyPath,
                     traitWorkerList);
@@ -588,32 +723,48 @@ namespace Xunit.Runner.Wpf.ViewModel
                     TestsSkipped++;
                 }
 
+                this.allTestCaseUniqueIDs.Add(testCase.UniqueID);
                 this.allTestCases.Add(testCaseViewModel);
             }
         }
 
-        private void OnTestsFinished(IEnumerable<TestResultData> testResultData)
+        private void OnTestStateChange(IEnumerable<TestResultData> testResultData)
         {
-            Debug.Assert(this.runningTests != null);
+            Debug.Assert(this.testsToRun != null);
 
             foreach (var result in testResultData)
             {
-                var testCase = this.runningTests.Single(x => x.DisplayName == result.TestCaseDisplayName);
+                var testCase = this.testsToRun.Single(x => x.UniqueID == result.TestCaseUniqueID);
                 testCase.State = result.TestState;
 
-                TestsCompleted++;
-                switch (result.TestState)
+                if (result.TestState == TestState.Running)
                 {
-                    case TestState.Passed:
-                        TestsPassed++;
-                        break;
-                    case TestState.Failed:
-                        TestsFailed++;
-                        Output = Output + result.Output;
-                        break;
-                    case TestState.Skipped:
-                        TestsSkipped++;
-                        break;
+                    if (runningTestSet.Add(result.TestCaseUniqueID))
+                    {
+                        TestsRunning++;
+                    }
+                }
+                else
+                {
+                    if (runningTestSet.Remove(result.TestCaseUniqueID))
+                    {
+                        TestsRunning--;
+                    }
+
+                    TestsCompleted++;
+                    switch (result.TestState)
+                    {
+                        case TestState.Passed:
+                            TestsPassed++;
+                            break;
+                        case TestState.Failed:
+                            TestsFailed++;
+                            Output = Output + result.Output;
+                            break;
+                        case TestState.Skipped:
+                            TestsSkipped++;
+                            break;
+                    }
                 }
 
                 if (result.TestState > CurrentRunState)
@@ -631,7 +782,7 @@ namespace Xunit.Runner.Wpf.ViewModel
         private void OnExecuteCancel()
         {
             Debug.Assert(CanExecuteCancel());
-            this.cancellationTokenSource.Cancel();
+            cancellationTokenSource?.Cancel();
         }
 
         private void OnExecuteTraitCheckedChanged(TraitViewModel trait)
@@ -677,6 +828,41 @@ namespace Xunit.Runner.Wpf.ViewModel
         {
             RemoveAssemblies(Assemblies.ToArray());
         }
+        private void OnToggleAutoReloadAssemblies()
+        {
+            ToggleReloadAssemblies();
+        }
+
+        private void ToggleReloadAssemblies()
+        {
+            this.settings.ToggleAutoReloadAssemblies();
+            AutoReloadAssemblies = this.settings.GetAutoReloadAssemblies();
+            UpdateAutoReloadStatus();
+        }
+
+        private void UpdateAutoReloadStatus()
+        {
+            if (AutoReloadAssemblies)
+            {
+                assemblyWatcher.EnableWatch(ReloadAssemblies);
+            }
+            else
+            {
+                assemblyWatcher.DisableWatch();
+            }
+        }
+
+        public bool FilterRunningTests
+        {
+            get { return searchQuery.FilterRunningTests; }
+            set
+            {
+                if (Set(ref searchQuery.FilterRunningTests, value))
+                {
+                    FilterAfterDelay();
+                }
+            }
+        }
 
         public bool FilterPassedTests
         {
@@ -720,7 +906,17 @@ namespace Xunit.Runner.Wpf.ViewModel
         public static TestComparer Instance { get; } = new TestComparer();
 
         public int Compare(TestCaseViewModel x, TestCaseViewModel y)
-            => StringComparer.Ordinal.Compare(x.DisplayName, y.DisplayName);
+        {
+            int result = StringComparer.OrdinalIgnoreCase.Compare(x.DisplayName, y.DisplayName);
+            if (result != 0)
+                return result;
+
+            result = StringComparer.Ordinal.Compare(x.DisplayName, y.DisplayName);
+            if (result != 0)
+                return result;
+
+            return StringComparer.Ordinal.Compare(x.UniqueID, y.UniqueID);
+        }
 
         private TestComparer() { }
     }

xunit.runner.wpf/ViewModel/SearchQuery.cs

@@ -4,6 +4,7 @@ namespace Xunit.Runner.Wpf.ViewModel
 {
     public class SearchQuery
     {
+        public bool FilterRunningTests = false;
         public bool FilterFailedTests = false;
         public bool FilterPassedTests = false;
         public bool FilterSkippedTests = false;

xunit.runner.wpf/ViewModel/TestCaseViewModel.cs

@@ -10,9 +10,11 @@ namespace Xunit.Runner.Wpf.ViewModel
         private TestState _state = TestState.NotRun;
 
         public string DisplayName { get; }
+        public string UniqueID { get; }
         public string SkipReason { get; }
         public string AssemblyFileName { get; }
         public ImmutableArray<TraitViewModel> Traits { get; }
+        public bool IsSelected { get; set; }
 
         public bool HasSkipReason => !string.IsNullOrEmpty(this.SkipReason);
 
@@ -22,9 +24,10 @@ namespace Xunit.Runner.Wpf.ViewModel
             set { Set(ref _state, value); }
         }
 
-        public TestCaseViewModel(string displayName, string skipReason, string assemblyFileName, IEnumerable<TraitViewModel> traits)
+        public TestCaseViewModel(string displayName, string uniqueID, string skipReason, string assemblyFileName, IEnumerable<TraitViewModel> traits)
         {
             this.DisplayName = displayName;
+            this.UniqueID = uniqueID;
             this.SkipReason = skipReason;
             this.AssemblyFileName = assemblyFileName;
             this.Traits = traits.ToImmutableArray();

xunit.runner.wpf/ViewModel/TraitViewModel.cs

@@ -7,7 +7,7 @@ namespace Xunit.Runner.Wpf.ViewModel
 {
     public partial class TraitViewModel : ViewModelBase
     {
-        private readonly TraitViewModel _parent;
+        private readonly TraitViewModel? _parent;
         private bool? _isChecked;
         private bool _isExpanded;
         private string _text;
@@ -19,7 +19,7 @@ namespace Xunit.Runner.Wpf.ViewModel
         {
         }
 
-        private TraitViewModel(TraitViewModel parent, string text)
+        private TraitViewModel(TraitViewModel? parent, string text)
         {
             this._parent = parent;
             this._isChecked = false;

xunit.runner.wpf/packages.config

@@ -3,16 +3,17 @@
   <package id="CommonServiceLocator" version="1.3" targetFramework="net452" />
   <package id="MvvmLight" version="5.3.0.0" targetFramework="net46" />
   <package id="MvvmLightLibs" version="5.3.0.0" targetFramework="net46" />
-  <package id="NuGet.CommandLine" version="3.4.3" targetFramework="net46" developmentDependency="true" />
-  <package id="System.Collections" version="4.0.10" targetFramework="net46" />
-  <package id="System.Collections.Immutable" version="1.1.37" targetFramework="net452" />
-  <package id="System.Diagnostics.Debug" version="4.0.10" targetFramework="net46" />
-  <package id="System.Globalization" version="4.0.10" targetFramework="net46" />
-  <package id="System.Linq" version="4.0.0" targetFramework="net46" />
-  <package id="System.Resources.ResourceManager" version="4.0.0" targetFramework="net46" />
-  <package id="System.Runtime" version="4.0.20" targetFramework="net46" />
-  <package id="System.Runtime.Extensions" version="4.0.10" targetFramework="net46" />
-  <package id="System.Threading" version="4.0.10" targetFramework="net46" />
+  <package id="NuGet.CommandLine" version="2.8.3" targetFramework="net46" />
+  <package id="System.Collections" version="4.3.0" targetFramework="net46" />
+  <package id="System.Collections.Immutable" version="1.4.0-preview1-25305-02" targetFramework="net46" />
+  <package id="System.Diagnostics.Debug" version="4.3.0" targetFramework="net46" />
+  <package id="System.Globalization" version="4.3.0" targetFramework="net46" />
+  <package id="System.Linq" version="4.3.0" targetFramework="net46" />
+  <package id="System.Resources.ResourceManager" version="4.3.0" targetFramework="net46" />
+  <package id="System.Runtime" version="4.3.0" targetFramework="net46" />
+  <package id="System.Runtime.Extensions" version="4.3.0" targetFramework="net46" />
+  <package id="System.Threading" version="4.3.0" targetFramework="net46" />
+  <package id="Tvl.NuGet.BuildTasks" version="1.0.0-alpha002" targetFramework="net46" developmentDependency="true" />
   <package id="WindowsAPICodePack-Core" version="1.1.2" targetFramework="net46" />
   <package id="WindowsAPICodePack-Shell" version="1.1.1" targetFramework="net46" />
   <package id="xunit.abstractions" version="2.0.0" targetFramework="net452" />

xunit.runner.wpf/xunit.runner.wpf.csproj

@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="14.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Import Project="..\packages\Tvl.NuGet.BuildTasks.1.0.0-alpha002\build\Tvl.NuGet.BuildTasks.props" Condition="Exists('..\packages\Tvl.NuGet.BuildTasks.1.0.0-alpha002\build\Tvl.NuGet.BuildTasks.props')" />
   <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
   <PropertyGroup>
     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
@@ -68,10 +69,10 @@
       <Private>True</Private>
     </Reference>
     <Reference Include="System" />
-    <Reference Include="System.Collections.Immutable, Version=1.1.37.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
-      <HintPath>..\packages\System.Collections.Immutable.1.1.37\lib\portable-net45+win8+wp8+wpa81\System.Collections.Immutable.dll</HintPath>
-      <Private>True</Private>
+    <Reference Include="System.Collections.Immutable, Version=1.2.2.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <HintPath>..\packages\System.Collections.Immutable.1.4.0-preview1-25305-02\lib\portable-net45+win8+wp8+wpa81\System.Collections.Immutable.dll</HintPath>
     </Reference>
+    <Reference Include="System.ComponentModel.Composition" />
     <Reference Include="System.Data" />
     <Reference Include="System.Windows.Interactivity, Version=4.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
       <HintPath>..\packages\MvvmLightLibs.5.3.0.0\lib\net45\System.Windows.Interactivity.dll</HintPath>
@@ -106,6 +107,8 @@
     <Compile Include="Impl\RemoteTestUtil.Connection.cs" />
     <Compile Include="Impl\RemoteTestUtil.BackgroundRunner.cs" />
     <Compile Include="Impl\RemoteTestUtil.cs" />
+    <Compile Include="Impl\TestAssemblyWatcher.cs" />
+    <Compile Include="ITestAssemblyWatcher.cs" />
     <Compile Include="ITestUtil.cs" />
     <Compile Include="Persistence\Settings.cs" />
     <Compile Include="Persistence\Storage.cs" />
@@ -149,10 +152,17 @@
     </EmbeddedResource>
     <None Include="packages.config" />
     <AppDesigner Include="Properties\" />
-    <None Include="xunit.runner.wpf.nuspec">
+    <None Include="xunit.runner.wpf.targets">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+      <SubType>Designer</SubType>
     </None>
   </ItemGroup>
+  <ItemGroup>
+    <NuGetManifest Include="xunit.runner.wpf.nuspec">
+      <Version>$(NuPkgVersion)</Version>
+      <PackageAnalysis>False</PackageAnalysis>
+    </NuGetManifest>
+  </ItemGroup>
   <ItemGroup>
     <None Include="App.config" />
   </ItemGroup>
@@ -192,10 +202,19 @@
   <ItemGroup>
     <Resource Include="Artwork\Application.ico" />
   </ItemGroup>
+  <ItemGroup>
+    <Resource Include="Artwork\Running_large.png" />
+  </ItemGroup>
+  <ItemGroup>
+    <Resource Include="Artwork\Running_small.png" />
+  </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
-  <Target Name="AfterBuild">
-    <Exec Command="&quot;$(SolutionDir)packages\NuGet.CommandLine.3.4.3\tools\NuGet.exe&quot; pack xunit.runner.wpf.nuspec -Version $(NuPkgVersion) -OutputDirectory ." WorkingDirectory="$(OutDir)" LogStandardErrorAsError="true" ConsoleToMSBuild="true">
-      <Output TaskParameter="ConsoleOutput" PropertyName="OutputOfExec" />
-    </Exec>
+  <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
+    <PropertyGroup>
+      <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
+    </PropertyGroup>
+    <Error Condition="!Exists('..\packages\Tvl.NuGet.BuildTasks.1.0.0-alpha002\build\Tvl.NuGet.BuildTasks.props')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\Tvl.NuGet.BuildTasks.1.0.0-alpha002\build\Tvl.NuGet.BuildTasks.props'))" />
+    <Error Condition="!Exists('..\packages\Tvl.NuGet.BuildTasks.1.0.0-alpha002\build\Tvl.NuGet.BuildTasks.targets')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\Tvl.NuGet.BuildTasks.1.0.0-alpha002\build\Tvl.NuGet.BuildTasks.targets'))" />
   </Target>
-</Project>
+  <Import Project="..\packages\Tvl.NuGet.BuildTasks.1.0.0-alpha002\build\Tvl.NuGet.BuildTasks.targets" Condition="Exists('..\packages\Tvl.NuGet.BuildTasks.1.0.0-alpha002\build\Tvl.NuGet.BuildTasks.targets')" />
+</Project>

xunit.runner.wpf/xunit.runner.wpf.nuspec

@@ -12,8 +12,9 @@
     <tags>XUnit Gui test runner</tags>
   </metadata>
   <files>
-    <file src="*.dll" target="tools\"/>
-    <file src="*.exe" target="tools\" exclude="*vshost*"/>
-    <file src="*.config" target="tools\" exclude="*vshost*"/>
+    <file src="bin\$Configuration$\*.dll" target="tools\"/>
+    <file src="xunit.runner.wpf.targets" target="build\net45"/>
+    <file src="bin\$Configuration$\*.exe" target="tools\" exclude="**\*vshost*"/>
+    <file src="bin\$Configuration$\*.config" target="tools\" exclude="**\*vshost*"/>
   </files>
 </package>

xunit.runner.wpf/xunit.runner.wpf.targets

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="14.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <PropertyGroup>
+    <StartAction Condition="'$(StartActions)' == ''">Program</StartAction>
+    <StartProgram Condition="'$(StartProgram)' == ''">$(MSBuildThisFileDirectory)..\tools\xunit.runner.wpf.exe</StartProgram>
+    <StartArguments Condition="'$(StartArguments)' == ''">$(AssemblyName).dll</StartArguments>
+    <StartWorkingDirectory Condition="'$(StartWorkingDirectory)' == ''">$(OutputDirectory)</StartWorkingDirectory>
+  </PropertyGroup>
+</Project>