[Bug]: Test discovery not working in VS Code

[aradalvand]

Description

I'm perplexed by the fact that this issue hasn't been filed already, because this has been a problem for a month now, and I've just been waiting for it to get fixed ever since as I assumed it's the most obvious bug anybody on VS Code could run into when using TUnit.

Expected Behavior

The tests should be discovered, as they were before.

Actual Behavior

Only the test projects are discovered, not the actual tests themselves. And even when you right-click on the test project names in the Test Explorer and run them, no tests are actually executed.

This is a screen recording I took that compares TUnit vs xUnit in this regard:

2026-06-26.17-57-38.trimmed.mp4

Steps to Reproduce

• Install .NET SDK 10.0.102
• Install VS Code + the C# Dev Kit extension (versions 1.126.0 and 3.20.199 respectively)
• Run dotnet new install TUnit.Templates
• Run dotnet new TUnit -o ./tunit-test-discovery-test
• Open the tunit-test-discovery-test directory with VS Code using code ./tunit-test-discovery-test
• Select the tests tab on the sidebar
• Notice that no tests are discovered, only test projects.

TUnit Version

1.56.35

.NET Version

10.0.102

Operating System

Linux

IDE / Test Runner

VS Code

Error Output / Stack Trace

Some C# Dev Kit - Test Explorer logs I've observed in a different project:

2026-06-26 17:45:39.672 [info] Created Test Controller (Lightweight Test Experience)
2026-06-26 17:45:39.672 [info] Log verbosity: Info
2026-06-26 17:45:39.672 [info] C# Dev Kit version: 3.20.199
2026-06-26 17:45:41.777 [info] Initialized Test Explorer Server [175980]
2026-06-26 17:45:41.793 [info] Found global.json at /home/arad/ahura/zurvan-second/global.json
2026-06-26 17:45:41.793 [info] Found dotnet sdk in /home/arad/dotnet/sdk/10.0.102.
2026-06-26 17:45:41.907 [info] No cached projects found.
2026-06-26 17:45:55.346 [info] Discovering tests in project '/home/arad/ahura/zurvan-second/Shenas/test/Shenas.InfraTests/Shenas.InfraTests.csproj' (TestingPlatform: True)
2026-06-26 17:45:55.351 [info] Discovery: /home/arad/ahura/zurvan-second/artifacts/bin/Shenas.InfraTests/debug/Shenas.InfraTests.dll (MTP: True)
2026-06-26 17:45:55.357 [info] Starting discovery for 1 sources.
2026-06-26 17:45:55.370 [error] Connection to test host '/home/arad/ahura/zurvan-second/artifacts/bin/Shenas.InfraTests/debug/Shenas.InfraTests.dll' was cancelled before it could be established. The test runner process did not connect within the allowed time.
2026-06-26 17:45:55.373 [error] System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at Microsoft.VisualStudio.Threading.ThreadingTools.WithCancellationSlow[T](Task`1 task, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClient.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, IProcessFactory processFactory, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, IInternalLogger logger, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.DefaultProfile.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.ClientServerProvider.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.TestingPlatformClientProvider.GetOrLaunchClientAsync(String source, String launcherType, String launcherConfiguration, RunSettingsInfo runSettingsInfo, Boolean singleUse, Boolean launchDebugger, IDictionary`2 environmentVariables, CancellationToken cancellationToken)
2026-06-26 17:45:55.374 [info] Discovery complete for '/home/arad/ahura/zurvan-second/artifacts/bin/Shenas.InfraTests/debug/Shenas.InfraTests.dll'
2026-06-26 17:45:58.881 [info] Discovering tests in project '/home/arad/ahura/zurvan-second/Shenas/test/Shenas.Tests/Shenas.Tests.csproj' (TestingPlatform: True)
2026-06-26 17:45:58.882 [info] Discovery: /home/arad/ahura/zurvan-second/artifacts/bin/Shenas.Tests/debug/Shenas.Tests.dll (MTP: True)
2026-06-26 17:45:58.883 [info] Starting discovery for 1 sources.
2026-06-26 17:45:58.887 [error] Connection to test host '/home/arad/ahura/zurvan-second/artifacts/bin/Shenas.Tests/debug/Shenas.Tests.dll' was cancelled before it could be established. The test runner process did not connect within the allowed time.
2026-06-26 17:45:58.887 [error] System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at Microsoft.VisualStudio.Threading.ThreadingTools.WithCancellationSlow[T](Task`1 task, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClient.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, IProcessFactory processFactory, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, IInternalLogger logger, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.DefaultProfile.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.ClientServerProvider.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.TestingPlatformClientProvider.GetOrLaunchClientAsync(String source, String launcherType, String launcherConfiguration, RunSettingsInfo runSettingsInfo, Boolean singleUse, Boolean launchDebugger, IDictionary`2 environmentVariables, CancellationToken cancellationToken)
2026-06-26 17:45:58.887 [info] Discovery complete for '/home/arad/ahura/zurvan-second/artifacts/bin/Shenas.Tests/debug/Shenas.Tests.dll'
2026-06-26 17:46:03.380 [info] Discovering tests in project '/home/arad/ahura/zurvan-second/Avesta/test/Avesta.Core.Tests/Avesta.Core.Tests.csproj' (TestingPlatform: True)
2026-06-26 17:46:03.381 [info] Discovery: /home/arad/ahura/zurvan-second/artifacts/bin/Avesta.Core.Tests/debug/Avesta.Core.Tests.dll (MTP: True)
2026-06-26 17:46:03.381 [info] Starting discovery for 1 sources.
2026-06-26 17:46:03.383 [error] Connection to test host '/home/arad/ahura/zurvan-second/artifacts/bin/Avesta.Core.Tests/debug/Avesta.Core.Tests.dll' was cancelled before it could be established. The test runner process did not connect within the allowed time.
2026-06-26 17:46:03.385 [error] System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at Microsoft.VisualStudio.Threading.ThreadingTools.WithCancellationSlow[T](Task`1 task, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClient.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, IProcessFactory processFactory, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, IInternalLogger logger, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.DefaultProfile.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.ClientServerProvider.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.TestingPlatformClientProvider.GetOrLaunchClientAsync(String source, String launcherType, String launcherConfiguration, RunSettingsInfo runSettingsInfo, Boolean singleUse, Boolean launchDebugger, IDictionary`2 environmentVariables, CancellationToken cancellationToken)
2026-06-26 17:46:03.386 [info] Discovery complete for '/home/arad/ahura/zurvan-second/artifacts/bin/Avesta.Core.Tests/debug/Avesta.Core.Tests.dll'
2026-06-26 17:46:03.896 [info] Discovering tests in project '/home/arad/ahura/zurvan-second/Sima/test/Sima.Tests/Sima.Tests.csproj' (TestingPlatform: True)
2026-06-26 17:46:03.897 [info] Discovery: /home/arad/ahura/zurvan-second/artifacts/bin/Sima.Tests/debug/Sima.Tests.dll (MTP: True)
2026-06-26 17:46:03.898 [info] Starting discovery for 1 sources.
2026-06-26 17:46:03.900 [error] Connection to test host '/home/arad/ahura/zurvan-second/artifacts/bin/Sima.Tests/debug/Sima.Tests.dll' was cancelled before it could be established. The test runner process did not connect within the allowed time.
2026-06-26 17:46:03.900 [error] System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at Microsoft.VisualStudio.Threading.ThreadingTools.WithCancellationSlow[T](Task`1 task, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClient.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, IProcessFactory processFactory, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, IInternalLogger logger, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.DefaultProfile.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.ClientServerProvider.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.TestingPlatformClientProvider.GetOrLaunchClientAsync(String source, String launcherType, String launcherConfiguration, RunSettingsInfo runSettingsInfo, Boolean singleUse, Boolean launchDebugger, IDictionary`2 environmentVariables, CancellationToken cancellationToken)
2026-06-26 17:46:03.902 [info] Discovery complete for '/home/arad/ahura/zurvan-second/artifacts/bin/Sima.Tests/debug/Sima.Tests.dll'
2026-06-26 17:46:04.710 [info] Discovering tests in project '/home/arad/ahura/zurvan-second/Sima/test/Sima.InfraTests/Sima.InfraTests.csproj' (TestingPlatform: True)
2026-06-26 17:46:04.710 [info] Discovery: /home/arad/ahura/zurvan-second/artifacts/bin/Sima.InfraTests/debug/Sima.InfraTests.dll (MTP: True)
2026-06-26 17:46:04.711 [info] Starting discovery for 1 sources.
2026-06-26 17:46:04.713 [error] Connection to test host '/home/arad/ahura/zurvan-second/artifacts/bin/Sima.InfraTests/debug/Sima.InfraTests.dll' was cancelled before it could be established. The test runner process did not connect within the allowed time.
2026-06-26 17:46:04.714 [error] System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at Microsoft.VisualStudio.Threading.ThreadingTools.WithCancellationSlow[T](Task`1 task, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClient.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, IProcessFactory processFactory, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, IInternalLogger logger, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.DefaultProfile.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.ClientServerProvider.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.TestingPlatformClientProvider.GetOrLaunchClientAsync(String source, String launcherType, String launcherConfiguration, RunSettingsInfo runSettingsInfo, Boolean singleUse, Boolean launchDebugger, IDictionary`2 environmentVariables, CancellationToken cancellationToken)
2026-06-26 17:46:04.714 [info] Discovery complete for '/home/arad/ahura/zurvan-second/artifacts/bin/Sima.InfraTests/debug/Sima.InfraTests.dll'
2026-06-26 17:46:08.275 [info] Running tests in project '/home/arad/ahura/zurvan-second/Sima/test/Sima.InfraTests/Sima.InfraTests.csproj' (TestingPlatform: True)
2026-06-26 17:46:08.277 [info] Run: /home/arad/ahura/zurvan-second/artifacts/bin/Sima.InfraTests/debug/Sima.InfraTests.dll (MTP: True)
2026-06-26 17:46:08.290 [error] Connection to test host '/home/arad/ahura/zurvan-second/artifacts/bin/Sima.InfraTests/debug/Sima.InfraTests.dll' was cancelled before it could be established. The test runner process did not connect within the allowed time.
2026-06-26 17:46:08.290 [error] System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at Microsoft.VisualStudio.Threading.ThreadingTools.WithCancellationSlow[T](Task`1 task, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClient.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, IProcessFactory processFactory, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, IInternalLogger logger, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.DefaultProfile.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.ClientServerProvider.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.TestingPlatformClientProvider.GetOrLaunchClientAsync(String source, String launcherType, String launcherConfiguration, RunSettingsInfo runSettingsInfo, Boolean singleUse, Boolean launchDebugger, IDictionary`2 environmentVariables, CancellationToken cancellationToken)
2026-06-26 17:46:08.291 [info] Run complete for '/home/arad/ahura/zurvan-second/artifacts/bin/Sima.InfraTests/debug/Sima.InfraTests.dll'
2026-06-26 17:46:21.543 [info] Discovering tests in project '/home/arad/ahura/zurvan-second/Jarchi/test/Jarchi.Tests/Jarchi.Tests.csproj' (TestingPlatform: True)
2026-06-26 17:46:21.544 [info] Discovery: /home/arad/ahura/zurvan-second/artifacts/bin/Jarchi.Tests/debug/Jarchi.Tests.dll (MTP: True)
2026-06-26 17:46:21.545 [info] Starting discovery for 1 sources.
2026-06-26 17:46:21.546 [error] Connection to test host '/home/arad/ahura/zurvan-second/artifacts/bin/Jarchi.Tests/debug/Jarchi.Tests.dll' was cancelled before it could be established. The test runner process did not connect within the allowed time.
2026-06-26 17:46:21.547 [error] System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at Microsoft.VisualStudio.Threading.ThreadingTools.WithCancellationSlow[T](Task`1 task, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClient.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, IProcessFactory processFactory, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, IInternalLogger logger, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.DefaultProfile.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.ClientServerProvider.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.TestingPlatformClientProvider.GetOrLaunchClientAsync(String source, String launcherType, String launcherConfiguration, RunSettingsInfo runSettingsInfo, Boolean singleUse, Boolean launchDebugger, IDictionary`2 environmentVariables, CancellationToken cancellationToken)
2026-06-26 17:46:21.547 [info] Discovery complete for '/home/arad/ahura/zurvan-second/artifacts/bin/Jarchi.Tests/debug/Jarchi.Tests.dll'
2026-06-26 17:46:22.196 [info] Discovering tests in project '/home/arad/ahura/zurvan-second/Jarchi/test/Jarchi.InfraTests/Jarchi.InfraTests.csproj' (TestingPlatform: True)
2026-06-26 17:46:22.196 [info] Discovery: /home/arad/ahura/zurvan-second/artifacts/bin/Jarchi.InfraTests/debug/Jarchi.InfraTests.dll (MTP: True)
2026-06-26 17:46:22.197 [info] Starting discovery for 1 sources.
2026-06-26 17:46:22.199 [error] Connection to test host '/home/arad/ahura/zurvan-second/artifacts/bin/Jarchi.InfraTests/debug/Jarchi.InfraTests.dll' was cancelled before it could be established. The test runner process did not connect within the allowed time.
2026-06-26 17:46:22.199 [error] System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at Microsoft.VisualStudio.Threading.ThreadingTools.WithCancellationSlow[T](Task`1 task, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClient.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, IProcessFactory processFactory, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, IInternalLogger logger, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.DefaultProfile.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.ClientServerProvider.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.TestingPlatformClientProvider.GetOrLaunchClientAsync(String source, String launcherType, String launcherConfiguration, RunSettingsInfo runSettingsInfo, Boolean singleUse, Boolean launchDebugger, IDictionary`2 environmentVariables, CancellationToken cancellationToken)
2026-06-26 17:46:22.199 [info] Discovery complete for '/home/arad/ahura/zurvan-second/artifacts/bin/Jarchi.InfraTests/debug/Jarchi.InfraTests.dll'
2026-06-26 17:46:22.459 [info] Discovering tests in project '/home/arad/ahura/zurvan-second/Goftar/test/Goftar.Tests/Goftar.Tests.csproj' (TestingPlatform: True)
2026-06-26 17:46:22.460 [info] Discovery: /home/arad/ahura/zurvan-second/artifacts/bin/Goftar.Tests/debug/Goftar.Tests.dll (MTP: True)
2026-06-26 17:46:22.461 [info] Starting discovery for 1 sources.
2026-06-26 17:46:22.463 [error] Connection to test host '/home/arad/ahura/zurvan-second/artifacts/bin/Goftar.Tests/debug/Goftar.Tests.dll' was cancelled before it could be established. The test runner process did not connect within the allowed time.
2026-06-26 17:46:22.464 [error] System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at Microsoft.VisualStudio.Threading.ThreadingTools.WithCancellationSlow[T](Task`1 task, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClient.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, IProcessFactory processFactory, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, IInternalLogger logger, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.DefaultProfile.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.ClientServerProvider.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.TestingPlatformClientProvider.GetOrLaunchClientAsync(String source, String launcherType, String launcherConfiguration, RunSettingsInfo runSettingsInfo, Boolean singleUse, Boolean launchDebugger, IDictionary`2 environmentVariables, CancellationToken cancellationToken)
2026-06-26 17:46:22.464 [info] Discovery complete for '/home/arad/ahura/zurvan-second/artifacts/bin/Goftar.Tests/debug/Goftar.Tests.dll'
2026-06-26 17:46:22.660 [info] Discovering tests in project '/home/arad/ahura/zurvan-second/Avesta/test/Avesta.Infra.Tests/Avesta.Infra.Tests.csproj' (TestingPlatform: True)
2026-06-26 17:46:22.660 [info] Discovery: /home/arad/ahura/zurvan-second/artifacts/bin/Avesta.Infra.Tests/debug/Avesta.Infra.Tests.dll (MTP: True)
2026-06-26 17:46:22.661 [info] Starting discovery for 1 sources.
2026-06-26 17:46:22.663 [error] Connection to test host '/home/arad/ahura/zurvan-second/artifacts/bin/Avesta.Infra.Tests/debug/Avesta.Infra.Tests.dll' was cancelled before it could be established. The test runner process did not connect within the allowed time.
2026-06-26 17:46:22.663 [error] System.Threading.Tasks.TaskCanceledException: A task was canceled.
   at Microsoft.VisualStudio.Threading.ThreadingTools.WithCancellationSlow[T](Task`1 task, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClientConnectionManager.LaunchTestRunnerAndWaitForMainNodeConnectionAsync(TestingPlatformLaunchConfig config, InitializeRequestArgs initializeRequest, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Clients.TestingPlatformClient.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, IProcessFactory processFactory, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, IInternalLogger logger, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.DefaultProfile.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.ClientServerProvider.CreateTestingPlatformClient(TestingPlatformLaunchConfig config, ITestRunDataSink dataSink, TestingPlatformCallbackHandler callback, CancellationToken cancellationToken)
   at Microsoft.VisualStudio.TestWindow.Internal.RemoteAgent.TestingPlatform.Providers.TestingPlatformClientProvider.GetOrLaunchClientAsync(String source, String launcherType, String launcherConfiguration, RunSettingsInfo runSettingsInfo, Boolean singleUse, Boolean launchDebugger, IDictionary`2 environmentVariables, CancellationToken cancellationToken)
2026-06-26 17:46:22.663 [info] Discovery complete for '/home/arad/ahura/zurvan-second/artifacts/bin/Avesta.Infra.Tests/debug/Avesta.Infra.Tests.dll'

Additional Context

No response

IDE-Specific Issue?

• I've confirmed this issue occurs when running via dotnet test or dotnet run, not just in my IDE

[thomhurst]

It works fine for me

[aradalvand]

Hmm... Puzzling. I figured maybe it's my VS Code setup/extension, so I just tested it on a fresh VS Code Insiders installation, but observed the same issue!

Are you on Linux? Can you run dotnet --list-sdks real quick and share the output?

[thomhurst]

I'm on Windows - So wonder if this is an issue with Linux VS Code?