Add test run serialization feature

playground/TestPlatform.Playground/TestPlatform.Playground.csproj

@@ -62,7 +62,7 @@
       <FileToCopy Include="$(SourcePath)testhost\bin\$(Configuration)\net48\win7-x64\**\*.*" SubFolder="TestHostNetFramework\" />
 
       <!-- copy datacollectors" -->
-      <FileToCopy Include="$(SourcePath)datacollector\bin\$(Configuration)\net472\**\*.*" SubFolder="vstest.console\" />
+      <FileToCopy Include="$(SourcePath)datacollector\bin\$(Configuration)\net472\**\*.*" SubFolder="" />
       <FileToCopy Include="$(SourcePath)Microsoft.TestPlatform.Extensions.BlameDataCollector\bin\$(Configuration)\net472\**\*.*" SubFolder="Extensions\" />
       <FileToCopy Include="$(SourcePath)DataCollectors\Microsoft.TestPlatform.Extensions.EventLogCollector\bin\$(Configuration)\$(NetFrameworkMinimum)\**\*.*" SubFolder="Extensions\" />
       <FileToCopy Include="$(SourcePath)DataCollectors\DumpMinitool\bin\$(Configuration)\$(NetFrameworkMinimum)\win7-x64\**\*.*" SubFolder="Extensions\blame\" />

src/Microsoft.TestPlatform.Common/ExtensionDecorators/ExtensionDecoratorFactory.cs

@@ -0,0 +1,23 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using Microsoft.VisualStudio.TestPlatform.ObjectModel.Adapter;
+using Microsoft.VisualStudio.TestPlatform.Utilities;
+
+namespace Microsoft.VisualStudio.TestPlatform.Common.ExtensionDecorators;
+internal class ExtensionDecoratorFactory
+{
+    private readonly IFeatureFlag _featureFlag;
+
+    public ExtensionDecoratorFactory(IFeatureFlag featureFlag)
+    {
+        _featureFlag = featureFlag;
+    }
+
+    public ITestExecutor Decorate(ITestExecutor originalTestExecutor)
+    {
+        return _featureFlag.IsSet(FeatureFlag.DISABLE_SERIALIZETESTRUN_DECORATOR)
+            ? originalTestExecutor
+            : new SerializeTestRunDecorator(originalTestExecutor);
+    }
+}

src/Microsoft.TestPlatform.Common/ExtensionDecorators/SerializeTestRunDecorator.cs

@@ -0,0 +1,137 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Xml.Linq;
+
+using Microsoft.VisualStudio.TestPlatform.ObjectModel;
+using Microsoft.VisualStudio.TestPlatform.ObjectModel.Adapter;
+using Microsoft.VisualStudio.TestPlatform.ObjectModel.Logging;
+
+namespace Microsoft.VisualStudio.TestPlatform.Common.ExtensionDecorators;
+
+internal class SerializeTestRunDecorator : ITestExecutor, ITestExecutor2, IDisposable
+{
+    private readonly SemaphoreSlim _runSequentialEvent = new(1);
+
+    public ITestExecutor OriginalTestExecutor { get; private set; }
+
+    public SerializeTestRunDecorator(ITestExecutor originalTestExecutor)
+    {
+        OriginalTestExecutor = originalTestExecutor;
+    }
+
+    public void RunTests(IEnumerable<TestCase>? tests, IRunContext? runContext, IFrameworkHandle? frameworkHandle)
+    {
+        if (IsSerializeTestRunEnabled(runContext))
+        {
+            EqtTrace.Info($"SerializeTestRunDecorator: Test cases will run sequentially");
+            if (tests is null)
+            {
+                return;
+            }
+
+            foreach (TestCase testToRun in tests)
+            {
+                _runSequentialEvent.Wait();
+                OriginalTestExecutor.RunTests(new List<TestCase> { testToRun }, runContext, new SerializeTestRunDecoratorFrameworkHandle(frameworkHandle!, _runSequentialEvent));
+            }
+        }
+        else
+        {
+            OriginalTestExecutor.RunTests(tests, runContext, frameworkHandle);
+        }
+    }
+
+    public void RunTests(IEnumerable<string>? sources, IRunContext? runContext, IFrameworkHandle? frameworkHandle)
+    {
+        if (IsSerializeTestRunEnabled(runContext))
+        {
+            EqtTrace.Error(Resources.Resources.SerializeTestRunInvalidScenario);
+            frameworkHandle?.SendMessage(TestMessageLevel.Error, Resources.Resources.SerializeTestRunInvalidScenario);
+        }
+        else
+        {
+            OriginalTestExecutor.RunTests(sources, runContext, frameworkHandle);
+        }
+    }
+
+    public bool ShouldAttachToTestHost(IEnumerable<string>? sources, IRunContext runContext)
+    {
+        if (OriginalTestExecutor is ITestExecutor2 executor)
+        {
+            return executor.ShouldAttachToTestHost(sources, runContext);
+        }
+
+        // If the adapter doesn't implement the new test executor interface we should attach to
+        // the default test host by default to preserve old behavior.
+        return true;
+    }
+
+    public bool ShouldAttachToTestHost(IEnumerable<TestCase>? tests, IRunContext runContext)
+    {
+        if (OriginalTestExecutor is ITestExecutor2 executor)
+        {
+            return executor.ShouldAttachToTestHost(tests, runContext);
+        }
+
+        // If the adapter doesn't implement the new test executor interface we should attach to
+        // the default test host by default to preserve old behavior.
+        return true;
+    }
+
+    public void Cancel()
+        => OriginalTestExecutor.Cancel();
+
+    private static bool IsSerializeTestRunEnabled(IRunContext? runContext)
+    {
+        if (runContext is null || runContext.RunSettings is null || runContext.RunSettings.SettingsXml is null)
+        {
+            return false;
+        }
+
+        XElement runSettings = XElement.Parse(runContext.RunSettings.SettingsXml);
+        XElement? serializeTestRun = runSettings.Element("RunConfiguration")?.Element("ForceOneTestAtTimePerTestHost");
+        return serializeTestRun is not null && bool.TryParse(serializeTestRun.Value, out bool enabled) && enabled;
+    }
+
+    public void Dispose()
+        => _runSequentialEvent.Dispose();
+}
+
+internal class SerializeTestRunDecoratorFrameworkHandle : IFrameworkHandle
+{
+    private readonly IFrameworkHandle _frameworkHandle;
+    private readonly SemaphoreSlim _testEnd;
+
+    public SerializeTestRunDecoratorFrameworkHandle(IFrameworkHandle frameworkHandle, SemaphoreSlim testEnd)
+    {
+        _frameworkHandle = frameworkHandle;
+        _testEnd = testEnd;
+    }
+
+    public bool EnableShutdownAfterTestRun { get => _frameworkHandle.EnableShutdownAfterTestRun; set => _frameworkHandle.EnableShutdownAfterTestRun = value; }
+
+    public int LaunchProcessWithDebuggerAttached(string filePath, string? workingDirectory, string? arguments, IDictionary<string, string?>? environmentVariables)
+        => _frameworkHandle.LaunchProcessWithDebuggerAttached(filePath, workingDirectory, arguments, environmentVariables);
+
+    public void RecordAttachments(IList<AttachmentSet> attachmentSets)
+        => _frameworkHandle.RecordAttachments(attachmentSets);
+
+    public void RecordEnd(TestCase testCase, TestOutcome outcome)
+    {
+        _frameworkHandle.RecordEnd(testCase, outcome);
+        _testEnd.Release();
+    }
+
+    public void RecordResult(TestResult testResult)
+        => _frameworkHandle.RecordResult(testResult);
+
+    public void RecordStart(TestCase testCase)
+        => _frameworkHandle.RecordStart(testCase);
+
+    public void SendMessage(TestMessageLevel testMessageLevel, string message)
+        => _frameworkHandle.SendMessage(testMessageLevel, message);
+}

src/Microsoft.TestPlatform.Common/ExtensionFramework/Utilities/LazyExtension.cs

@@ -4,6 +4,10 @@
 using System;
 using System.Linq;
 
+using Microsoft.VisualStudio.TestPlatform.Common.ExtensionDecorators;
+using Microsoft.VisualStudio.TestPlatform.ObjectModel.Adapter;
+using Microsoft.VisualStudio.TestPlatform.Utilities;
+
 namespace Microsoft.VisualStudio.TestPlatform.Common.ExtensionFramework.Utilities;
 
 /// <summary>
@@ -16,6 +20,7 @@ public class LazyExtension<TExtension, TMetadata>
     private static readonly object Synclock = new();
     private readonly Type? _metadataType;
     private readonly Func<TExtension>? _extensionCreator;
+    private readonly ExtensionDecoratorFactory _extensionDecoratorFactory = new(FeatureFlag.Instance);
     private TExtension? _extension;
     private TMetadata? _metadata;
 
@@ -96,7 +101,15 @@ public TExtension Value
                             TPDebug.Assert(TestPluginInfo.AssemblyQualifiedName is not null, "TestPluginInfo.AssemblyQualifiedName is null");
                             var pluginType = TestPluginManager.GetTestExtensionType(TestPluginInfo.AssemblyQualifiedName);
                             TPDebug.Assert(pluginType is not null, "pluginType is null");
-                            _extension = TestPluginManager.CreateTestExtension<TExtension>(pluginType);
+
+                            // If the extension is a test executor we decorate the adapter to augment the test platform capabilities.
+                            var extension = TestPluginManager.CreateTestExtension<TExtension>(pluginType);
+                            if (typeof(ITestExecutor).IsAssignableFrom(typeof(TExtension)))
+                            {
+                                extension = (TExtension)_extensionDecoratorFactory.Decorate((ITestExecutor)extension!);
+                            }
+
+                            _extension = extension;
                         }
                     }
                 }

src/Microsoft.TestPlatform.Common/Resources/Resources.resx

@@ -207,6 +207,9 @@
   <data name="RunSettingsParseError" xml:space="preserve">
     <value>An error occurred while loading the run settings.  Error: {0}</value>
   </data>
+  <data name="SerializeTestRunInvalidScenario" xml:space="preserve">
+    <value>&lt;ForceOneTestAtTimePerTestHost&gt;true&lt;/ForceOneTestAtTimePerTestHost&gt; is not supported for sources test run</value>
+  </data>
   <data name="SettingsNodeInvalidName" xml:space="preserve">
     <value>Invalid settings node specified. The name property of the settings node must be non-empty.</value>
   </data>
@@ -231,4 +234,4 @@
   <data name="WrongDataCollectionContextType" xml:space="preserve">
     <value>Types deriving from the data collection context cannot be used for sending data and messages.  The DataCollectionContext used for sending data and messages must come from one of the events raised to the data collector.</value>
   </data>
-</root>
+</root>

src/Microsoft.TestPlatform.Common/Resources/xlf/Resources.cs.xlf

@@ -192,6 +192,11 @@
         <target state="translated">Trasování zásobníku:</target>
         <note></note>
       </trans-unit>
+      <trans-unit id="SerializeTestRunInvalidScenario">
+        <source>&lt;ForceOneTestAtTimePerTestHost&gt;true&lt;/ForceOneTestAtTimePerTestHost&gt; is not supported for sources test run</source>
+        <target state="new">&lt;SerializeTestRun&gt;true&lt;/SerializeTestRun&gt; is not supported for sources test run</target>
+        <note></note>
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Microsoft.TestPlatform.Common/Resources/xlf/Resources.de.xlf

@@ -192,6 +192,11 @@
         <target state="translated">Stapelüberwachung:</target>
         <note></note>
       </trans-unit>
+      <trans-unit id="SerializeTestRunInvalidScenario">
+        <source>&lt;ForceOneTestAtTimePerTestHost&gt;true&lt;/ForceOneTestAtTimePerTestHost&gt; is not supported for sources test run</source>
+        <target state="new">&lt;SerializeTestRun&gt;true&lt;/SerializeTestRun&gt; is not supported for sources test run</target>
+        <note></note>
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Microsoft.TestPlatform.Common/Resources/xlf/Resources.es.xlf

@@ -192,6 +192,11 @@
         <target state="translated">Seguimiento de la pila:</target>
         <note></note>
       </trans-unit>
+      <trans-unit id="SerializeTestRunInvalidScenario">
+        <source>&lt;ForceOneTestAtTimePerTestHost&gt;true&lt;/ForceOneTestAtTimePerTestHost&gt; is not supported for sources test run</source>
+        <target state="new">&lt;SerializeTestRun&gt;true&lt;/SerializeTestRun&gt; is not supported for sources test run</target>
+        <note></note>
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Microsoft.TestPlatform.Common/Resources/xlf/Resources.fr.xlf

@@ -192,6 +192,11 @@
         <target state="translated">Arborescence des appels de procédure :</target>
         <note></note>
       </trans-unit>
+      <trans-unit id="SerializeTestRunInvalidScenario">
+        <source>&lt;ForceOneTestAtTimePerTestHost&gt;true&lt;/ForceOneTestAtTimePerTestHost&gt; is not supported for sources test run</source>
+        <target state="new">&lt;SerializeTestRun&gt;true&lt;/SerializeTestRun&gt; is not supported for sources test run</target>
+        <note></note>
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Microsoft.TestPlatform.Common/Resources/xlf/Resources.it.xlf

@@ -192,6 +192,11 @@
         <target state="translated">Analisi dello stack:</target>
         <note></note>
       </trans-unit>
+      <trans-unit id="SerializeTestRunInvalidScenario">
+        <source>&lt;ForceOneTestAtTimePerTestHost&gt;true&lt;/ForceOneTestAtTimePerTestHost&gt; is not supported for sources test run</source>
+        <target state="new">&lt;SerializeTestRun&gt;true&lt;/SerializeTestRun&gt; is not supported for sources test run</target>
+        <note></note>
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Microsoft.TestPlatform.Common/Resources/xlf/Resources.ja.xlf

@@ -192,6 +192,11 @@
         <target state="translated">スタック トレース:</target>
         <note></note>
       </trans-unit>
+      <trans-unit id="SerializeTestRunInvalidScenario">
+        <source>&lt;ForceOneTestAtTimePerTestHost&gt;true&lt;/ForceOneTestAtTimePerTestHost&gt; is not supported for sources test run</source>
+        <target state="new">&lt;SerializeTestRun&gt;true&lt;/SerializeTestRun&gt; is not supported for sources test run</target>
+        <note></note>
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Microsoft.TestPlatform.Common/Resources/xlf/Resources.ko.xlf

@@ -192,6 +192,11 @@
         <target state="translated">스택 추적:</target>
         <note></note>
       </trans-unit>
+      <trans-unit id="SerializeTestRunInvalidScenario">
+        <source>&lt;ForceOneTestAtTimePerTestHost&gt;true&lt;/ForceOneTestAtTimePerTestHost&gt; is not supported for sources test run</source>
+        <target state="new">&lt;SerializeTestRun&gt;true&lt;/SerializeTestRun&gt; is not supported for sources test run</target>
+        <note></note>
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Microsoft.TestPlatform.Common/Resources/xlf/Resources.pl.xlf

@@ -192,6 +192,11 @@
         <target state="translated">Ślad stosu:</target>
         <note></note>
       </trans-unit>
+      <trans-unit id="SerializeTestRunInvalidScenario">
+        <source>&lt;ForceOneTestAtTimePerTestHost&gt;true&lt;/ForceOneTestAtTimePerTestHost&gt; is not supported for sources test run</source>
+        <target state="new">&lt;SerializeTestRun&gt;true&lt;/SerializeTestRun&gt; is not supported for sources test run</target>
+        <note></note>
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Microsoft.TestPlatform.Common/Resources/xlf/Resources.pt-BR.xlf

@@ -192,6 +192,11 @@
         <target state="translated">Rastreamento de pilha:</target>
         <note></note>
       </trans-unit>
+      <trans-unit id="SerializeTestRunInvalidScenario">
+        <source>&lt;ForceOneTestAtTimePerTestHost&gt;true&lt;/ForceOneTestAtTimePerTestHost&gt; is not supported for sources test run</source>
+        <target state="new">&lt;SerializeTestRun&gt;true&lt;/SerializeTestRun&gt; is not supported for sources test run</target>
+        <note></note>
+      </trans-unit>
     </body>
   </file>
 </xliff>

src/Microsoft.TestPlatform.Common/Resources/xlf/Resources.ru.xlf

@@ -192,6 +192,11 @@
         <target state="translated">Трассировка стека:</target>
         <note></note>
       </trans-unit>
+      <trans-unit id="SerializeTestRunInvalidScenario">
+        <source>&lt;ForceOneTestAtTimePerTestHost&gt;true&lt;/ForceOneTestAtTimePerTestHost&gt; is not supported for sources test run</source>
+        <target state="new">&lt;SerializeTestRun&gt;true&lt;/SerializeTestRun&gt; is not supported for sources test run</target>
+        <note></note>
+      </trans-unit>
     </body>
   </file>
 </xliff>