microsoft · Evangelink · May 25, 2026
diff --git a/src/Platform/Microsoft.Testing.Platform/Hosts/CommonTestHost.cs b/src/Platform/Microsoft.Testing.Platform/Hosts/CommonTestHost.cs
@@ -250,6 +250,8 @@ private static async Task NotifyTestSessionEndAsync(ITestSessionContext testSess
             return;
         }
 
+        IShutdownProgressReporter? shutdownProgressReporter = serviceProvider.GetService<IShutdownProgressReporter>();
+
         // First, we call OnTestSessionFinishingAsync on all non-consumers.
         bool hasNonDataConsumers = false;
         foreach (ITestSessionLifetimeHandler testSessionLifetimeHandler in testSessionLifetimeHandlersContainer.TestSessionLifetimeHandlers)
@@ -272,6 +274,7 @@ private static async Task NotifyTestSessionEndAsync(ITestSessionContext testSess
             hasNonDataConsumers = true;
 
             using (otelService?.StartActivity(testSessionLifetimeHandler.Uid, testSessionLifetimeHandler.ToOTelTags()))
+            using (shutdownProgressReporter?.Track(testSessionLifetimeHandler.Uid, testSessionLifetimeHandler.DisplayName, nameof(ITestSessionLifetimeHandler.OnTestSessionFinishingAsync)))
             {
                 await testSessionLifetimeHandler.OnTestSessionFinishingAsync(testSessionContext).ConfigureAwait(false);
             }
@@ -294,6 +297,7 @@ private static async Task NotifyTestSessionEndAsync(ITestSessionContext testSess
             }
 
             using (otelService?.StartActivity(testSessionLifetimeHandler.Uid, testSessionLifetimeHandler.ToOTelTags()))
+            using (shutdownProgressReporter?.Track(testSessionLifetimeHandler.Uid, testSessionLifetimeHandler.DisplayName, nameof(ITestSessionLifetimeHandler.OnTestSessionFinishingAsync)))
             {
                 await testSessionLifetimeHandler.OnTestSessionFinishingAsync(testSessionContext).ConfigureAwait(false);
             }

diff --git a/src/Platform/Microsoft.Testing.Platform/Hosts/TestHostBuilder.CommonServices.cs b/src/Platform/Microsoft.Testing.Platform/Hosts/TestHostBuilder.CommonServices.cs
@@ -182,6 +182,15 @@ private async Task<BuildContext> SetupCommonServicesAsync(
         serviceProvider.TryAddService(context.ProxyOutputDevice);
         serviceProvider.TryAddService(context.ProxyOutputDevice.OriginalOutputDevice);
 
+        // Reports extensions/consumers that have not yet completed once the test-application
+        // cancellation token is signalled. Registered after the output device so it can use it.
+        ShutdownProgressReporter shutdownProgressReporter = new(
+            context.TestApplicationCancellationTokenSource,
+            context.ProxyOutputDevice,
+            context.LoggerFactory,
+            systemClock);
+        serviceProvider.AddService(shutdownProgressReporter);
+
         context.TestFrameworkCapabilities = TestFramework!.TestFrameworkCapabilitiesFactory(serviceProvider);
         if (context.TestFrameworkCapabilities is IAsyncInitializableExtension testFrameworkCapabilitiesAsyncInitializable)
         {

diff --git a/src/Platform/Microsoft.Testing.Platform/Hosts/TestHostBuilder.Framework.cs b/src/Platform/Microsoft.Testing.Platform/Hosts/TestHostBuilder.Framework.cs
@@ -111,7 +111,8 @@ private static async Task<ITestFramework> BuildTestFrameworkAsync(TestFrameworkB
             serviceProvider.GetTestApplicationCancellationTokenSource(),
             serviceProvider.GetTask(),
             serviceProvider.GetLoggerFactory(),
-            serviceProvider.GetEnvironment());
+            serviceProvider.GetEnvironment(),
+            serviceProvider.GetService<IShutdownProgressReporter>());
         await concreteMessageBusService.InitAsync().ConfigureAwait(false);
         testFrameworkBuilderData.MessageBusProxy.SetBuiltMessageBus(concreteMessageBusService);
 

diff --git a/src/Platform/Microsoft.Testing.Platform/Hosts/TestHostControllersTestHost.cs b/src/Platform/Microsoft.Testing.Platform/Hosts/TestHostControllersTestHost.cs
@@ -175,7 +175,8 @@ protected override async Task<int> InternalRunAsync(CancellationToken cancellati
                 ServiceProvider.GetTestApplicationCancellationTokenSource(),
                 ServiceProvider.GetTask(),
                 ServiceProvider.GetLoggerFactory(),
-                ServiceProvider.GetEnvironment());
+                ServiceProvider.GetEnvironment(),
+                ServiceProvider.GetService<IShutdownProgressReporter>());
             await concreteMessageBusService.InitAsync().ConfigureAwait(false);
             ((MessageBusProxy)ServiceProvider.GetMessageBus()).SetBuiltMessageBus(concreteMessageBusService);
 

diff --git a/src/Platform/Microsoft.Testing.Platform/Messages/AsynchronousMessageBus.cs b/src/Platform/Microsoft.Testing.Platform/Messages/AsynchronousMessageBus.cs
@@ -24,6 +24,7 @@ internal sealed class AsynchronousMessageBus : BaseMessageBus, IMessageBus, IDis
     private readonly Dictionary<Type, List<IAsyncConsumerDataProcessor>> _dataTypeConsumers = [];
     private readonly IDataConsumer[] _dataConsumers;
     private readonly ITestApplicationCancellationTokenSource _testApplicationCancellationTokenSource;
+    private readonly IShutdownProgressReporter? _shutdownProgressReporter;
     private bool _disabled;
 
     public AsynchronousMessageBus(
@@ -32,11 +33,23 @@ public AsynchronousMessageBus(
         ITask task,
         ILoggerFactory loggerFactory,
         IEnvironment environment)
+        : this(dataConsumers, testApplicationCancellationTokenSource, task, loggerFactory, environment, shutdownProgressReporter: null)
+    {
+    }
+
+    public AsynchronousMessageBus(
+        IDataConsumer[] dataConsumers,
+        ITestApplicationCancellationTokenSource testApplicationCancellationTokenSource,
+        ITask task,
+        ILoggerFactory loggerFactory,
+        IEnvironment environment,
+        IShutdownProgressReporter? shutdownProgressReporter)
     {
         _dataConsumers = dataConsumers;
         _testApplicationCancellationTokenSource = testApplicationCancellationTokenSource;
         _task = task;
         _environment = environment;
+        _shutdownProgressReporter = shutdownProgressReporter;
         _logger = loggerFactory.CreateLogger<AsynchronousMessageBus>();
         _isTraceLoggingEnabled = _logger.IsEnabled(LogLevel.Trace);
     }
@@ -157,7 +170,10 @@ public override async Task DrainDataAsync()
 
             foreach (IAsyncConsumerDataProcessor processor in _consumerProcessor.Values)
             {
-                await processor.DrainDataAsync().ConfigureAwait(false);
+                using (_shutdownProgressReporter?.Track(processor.DataConsumer.Uid, processor.DataConsumer.DisplayName, nameof(IAsyncConsumerDataProcessor.DrainDataAsync)))
+                {
+                    await processor.DrainDataAsync().ConfigureAwait(false);
+                }
             }
 
             bool anyNewlyReceived = false;

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/PlatformResources.resx b/src/Platform/Microsoft.Testing.Platform/Resources/PlatformResources.resx
@@ -522,6 +522,10 @@ Read more about Microsoft Testing Platform telemetry: https://aka.ms/testingplat
   <data name="CancellingTestSession" xml:space="preserve">
     <value>Canceling the test session...</value>
   </data>
+  <data name="ShutdownProgressStillWaitingPrefix" xml:space="preserve">
+    <value>Still waiting for: </value>
+    <comment>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</comment>
+  </data>
   <data name="DiagnosticFileLevelWithAsyncFlush" xml:space="preserve">
     <value>Diagnostic file (level '{0}' with async flush): {1}</value>
     <comment>0 level such as verbose,

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.cs.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.cs.xlf
@@ -750,6 +750,11 @@ Může mít jenom jeden argument jako řetězec ve formátu &lt;value&gt;[h|m|s]
         <target state="translated">Instance typu ITestFramework by neměly být registrovány prostřednictvím poskytovatele služeb, ale prostřednictvím metody ITestApplicationBuilder.RegisterTestFramework.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">Přeskočeno</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.de.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.de.xlf
@@ -750,6 +750,11 @@ Nimmt ein Argument als Zeichenfolge im Format &lt;value&gt;[h|m|s], wobei "value
         <target state="translated">Instanzen vom Typ "ITestFramework" sollten nicht über den Dienstanbieter, sondern über "ITestApplicationBuilder.RegisterTestFramework" registriert werden.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">Übersprungen</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.es.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.es.xlf
@@ -750,6 +750,11 @@ Toma un argumento como cadena con el formato &lt;value&gt;[h|m|s] donde 'value'
         <target state="translated">Las instancias de tipo "ITestFramework" no deben registrarse mediante el proveedor de servicios, sino mediante "ITestApplicationBuilder.RegisterTestFramework".</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">Omitida</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.fr.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.fr.xlf
@@ -750,6 +750,11 @@ Prend un argument sous forme de chaîne au format &lt;value&gt;[h|m|s] où « v
         <target state="translated">Les instances de type « ITestFramework » ne doivent pas être inscrites par le biais du fournisseur de services, mais par le biais de « ITestApplicationBuilder.RegisterTestFramework »</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">Ignoré</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.it.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.it.xlf
@@ -750,6 +750,11 @@ Acquisisce un argomento come stringa nel formato &lt;value&gt;[h|m|s] dove 'valu
         <target state="translated">Le istanze di tipo 'ITestFramework' non devono essere registrate tramite il provider di servizi, ma tramite 'ITestApplicationBuilder.RegisterTestFramework'</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">Ignorato</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.ja.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.ja.xlf
@@ -751,6 +751,11 @@ Takes one argument as string in the format &lt;value&gt;[h|m|s] where 'value' is
         <target state="translated">'ITestFramework' 型のインスタンスは、サービス プロバイダーを介して登録することはできません。'ITestApplicationBuilder.RegisterTestFramework' を介して登録する必要があります</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">スキップ</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.ko.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.ko.xlf
@@ -750,6 +750,11 @@ Takes one argument as string in the format &lt;value&gt;[h|m|s] where 'value' is
         <target state="translated">'ITestFramework' 형식의 인스턴스는 서비스 공급자를 통해 등록하지 않아야 하지만 'ITestApplicationBuilder.RegisterTestFramework'를 통해 등록해야 합니다.</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">건너뜀</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.pl.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.pl.xlf
@@ -750,6 +750,11 @@ Pobiera jeden argument jako ciąg w formacie &lt;value&gt;[h|m|s], gdzie element
         <target state="translated">Wystąpienia typu „ITestFramework” nie powinny być rejestrowane za pośrednictwem dostawcy usług, ale za pośrednictwem elementu „ITestApplicationBuilder.RegisterTestFramework”</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">Pominięto</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.pt-BR.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.pt-BR.xlf
@@ -750,6 +750,11 @@ Recebe um argumento como cadeia de caracteres no formato &lt;valor&gt;[h|m|s] em
         <target state="translated">Instâncias do tipo "ITestFramework" não devem ser registradas por meio do provedor de serviços, mas por meio de "ITestApplicationBuilder.RegisterTestFramework"</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">Ignorado</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.ru.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.ru.xlf
@@ -750,6 +750,11 @@ Takes one argument as string in the format &lt;value&gt;[h|m|s] where 'value' is
         <target state="translated">Экземпляры типа "ITestFramework" следует регистрировать не через поставщика услуг, а через "ITestApplicationBuilder.RegisterTestFramework"</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">Пропущен</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.tr.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.tr.xlf
@@ -750,6 +750,11 @@ Bir bağımsız değişkeni, 'value' değerinin kayan olduğu &lt;value&gt;[h|m|
         <target state="translated">'ITestFramework' türündeki örnekler hizmet sağlayıcısı aracılığıyla değil, 'ITestApplicationBuilder.RegisterTestFramework' aracılığıyla kaydedilmelidir</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">Atlandı</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.zh-Hans.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.zh-Hans.xlf
@@ -750,6 +750,11 @@ Takes one argument as string in the format &lt;value&gt;[h|m|s] where 'value' is
         <target state="translated">不应通过服务提供商注册类型为“ITestFramework”的实例，而应通过“ITestApplicationBuilder.RegisterTestFramework”进行注册</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">已跳过</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.zh-Hant.xlf b/src/Platform/Microsoft.Testing.Platform/Resources/xlf/PlatformResources.zh-Hant.xlf
@@ -750,6 +750,11 @@ Takes one argument as string in the format &lt;value&gt;[h|m|s] where 'value' is
         <target state="translated">類型 'ITestFramework' 的執行個體不應透過服務提供者註冊，而是透過 'ITestApplicationBuilder.RegisterTestFramework' 註冊</target>
         <note />
       </trans-unit>
+      <trans-unit id="ShutdownProgressStillWaitingPrefix">
+        <source>Still waiting for: </source>
+        <target state="new">Still waiting for: </target>
+        <note>Prefix for the message that lists extensions that have not yet completed their shutdown work. Each entry is formatted as "{DisplayName} ({Phase}, {Seconds}s)" and entries are separated by "; ".</note>
+      </trans-unit>
       <trans-unit id="Skipped">
         <source>Skipped</source>
         <target state="translated">略過</target>

diff --git a/src/Platform/Microsoft.Testing.Platform/Services/IShutdownProgressReporter.cs b/src/Platform/Microsoft.Testing.Platform/Services/IShutdownProgressReporter.cs
@@ -0,0 +1,26 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+namespace Microsoft.Testing.Platform.Services;
+
+/// <summary>
+/// Tracks units of work that the platform is awaiting during shutdown so that, after
+/// cancellation has been requested, the user can be told which extensions are still
+/// running and how long each one has been blocking.
+/// </summary>
+/// <remarks>
+/// Implementations must be thread-safe. Callers wrap shutdown-relevant awaits with
+/// <c>using (reporter.Track(uid, displayName, phase)) { await ... }</c>; on the
+/// happy path (no cancellation) this is effectively a no-op beyond bookkeeping.
+/// </remarks>
+internal interface IShutdownProgressReporter
+{
+    /// <summary>
+    /// Registers a unit of in-flight work and returns a disposable that removes it.
+    /// </summary>
+    /// <param name="uid">Stable identifier of the extension / consumer being awaited.</param>
+    /// <param name="displayName">Human-readable name surfaced to the user.</param>
+    /// <param name="phase">Short label describing what we are awaiting (e.g. <c>OnTestSessionFinishingAsync</c>).</param>
+    /// <returns>A disposable that removes the tracker when the awaited work completes.</returns>
+    IDisposable Track(string uid, string displayName, string phase);
+}