Fix LaunchProfilesDebugLaunchProvider async completion handling (#9826)

This change resolves a potential deadlock issue by using IProjectFaultHandlerService.Forget to call OnAfterLaunchAsync

The pattern ensures that post-launch async work completes while avoiding deadlocks that could occur when ExecuteSynchronously blocks on async work that needs UI thread access.

Signed-off-by: Phil Henning <[email protected]>

Author: phenning

src/Microsoft.VisualStudio.ProjectSystem.Managed.VS/ProjectSystem/VS/Debug/LaunchProfilesDebugLaunchProvider.cs

@@ -24,17 +24,20 @@ internal class LaunchProfilesDebugLaunchProvider : DebugLaunchProviderBase, IDep
     private readonly ILaunchSettingsProvider _launchSettingsProvider;
     private IDebugProfileLaunchTargetsProvider? _lastLaunchProvider;
     private readonly IProjectThreadingService _threadingService;
+    private readonly IProjectFaultHandlerService _projectFaultHandlerService;
 
     [ImportingConstructor]
     public LaunchProfilesDebugLaunchProvider(
         ConfiguredProject configuredProject,
         ILaunchSettingsProvider launchSettingsProvider,
         IVsService<IVsDebuggerLaunchAsync> vsDebuggerService,
+        IProjectFaultHandlerService projectFaultHandlerService,
         [Import(AllowDefault = true)] IProjectThreadingService? threadingService = null)
         : base(configuredProject)
     {
         _launchSettingsProvider = launchSettingsProvider;
         _vsDebuggerService = vsDebuggerService;
+        _projectFaultHandlerService = projectFaultHandlerService;
         _threadingService = threadingService ?? ThreadingService;
 
         LaunchTargetsProviders = new OrderPrecedenceImportCollection<IDebugProfileLaunchTargetsProvider>(projectCapabilityCheckProvider: configuredProject.UnconfiguredProject);
@@ -135,11 +138,12 @@ private async Task<IReadOnlyList<IDebugLaunchSettings>> QueryDebugTargetsInterna
     }
 
     private sealed class LaunchCompleteCallback(
-        IProjectThreadingService threadingService,
         DebugLaunchOptions launchOptions,
         IDebugProfileLaunchTargetsProvider? targetsProvider,
         ILaunchProfile activeProfile,
-        IReadOnlyList<IDebugLaunchSettings> debugLaunchSettings)
+        IReadOnlyList<IDebugLaunchSettings> debugLaunchSettings,
+        IProjectFaultHandlerService projectFaultHandlerService,
+        UnconfiguredProject? unconfiguredProject)
         : IVsDebuggerLaunchCompletionCallback, IVsDebugProcessNotify1800
     {
         private readonly List<IVsLaunchedProcess> _launchedProcesses = new();
@@ -164,16 +168,22 @@ public void OnComplete(int hr, uint debugTargetCount, VsDebugTargetProcessInfo[]
                     processInfoArray.Length == 1 &&
                     vsLaunchedProcess is not null)
                 {
-                    threadingService.ExecuteSynchronously(() => targetsProvider5.OnAfterLaunchAsync(launchOptions, activeProfile, debugLaunchSettings[0], vsLaunchedProcess, processInfoArray[0]));
+                    projectFaultHandlerService.Forget(
+                        targetsProvider5.OnAfterLaunchAsync(launchOptions, activeProfile, debugLaunchSettings[0], vsLaunchedProcess, processInfoArray[0]),
+                        unconfiguredProject);
                 }
                 else
                 {
-                    threadingService.ExecuteSynchronously(() => targetsProvider4.OnAfterLaunchAsync(launchOptions, activeProfile, processInfoArray));
+                    projectFaultHandlerService.Forget(
+                        targetsProvider4.OnAfterLaunchAsync(launchOptions, activeProfile, processInfoArray),
+                        unconfiguredProject);
                 }
             }
             else if (targetsProvider is not null)
             {
-                threadingService.ExecuteSynchronously(() => targetsProvider.OnAfterLaunchAsync(launchOptions, activeProfile));
+                projectFaultHandlerService.Forget(
+                    targetsProvider.OnAfterLaunchAsync(launchOptions, activeProfile),
+                    unconfiguredProject);
             }
         }
 
@@ -216,8 +226,8 @@ public async Task LaunchWithProfileAsync(DebugLaunchOptions launchOptions, ILaun
         {
             await targetProvider.OnBeforeLaunchAsync(launchOptions, profile);
         }
-
-        LaunchCompleteCallback callback = new(ThreadingService, launchOptions, targetProvider, profile, targets);
+        
+        LaunchCompleteCallback callback = new(launchOptions, targetProvider, profile, targets, _projectFaultHandlerService, ConfiguredProject?.UnconfiguredProject);
 
         if (targets.Count == 0)
         {
@@ -240,7 +250,6 @@ public async Task LaunchWithProfileAsync(DebugLaunchOptions launchOptions, ILaun
 
             // The debugger needs to be called on the UI thread
             await _threadingService.SwitchToUIThread(cancellationToken);
-
             shellDebugger.LaunchDebugTargetsAsync((uint)launchSettingsNative.Length, launchSettingsNative, callback);
         }
         finally

tests/Microsoft.VisualStudio.ProjectSystem.Managed.VS.UnitTests/ProjectSystem/VS/Debug/LaunchProfilesDebugLaunchProviderTests.cs

@@ -113,11 +113,13 @@ public async Task LaunchWithProfileAsync_WhenNotProjectCommand_DoesNotCreateHotR
         var mockHotReloadOptionService = IHotReloadOptionServiceFactory.Create();
         var mockVsDebuggerService = Mock.Of<IVsDebuggerLaunchAsync>();
         var mockProjectThreadingService = IProjectThreadingServiceFactory.Create();
+        var mockProjectFaultHandlerService = IProjectFaultHandlerServiceFactory.Create();
 
         var provider = new LaunchProfilesDebugLaunchProvider(
             _configuredProjectMoq.Object,
             _launchSettingsProviderMoq.Object,
             IVsServiceFactory.Create(mockVsDebuggerService),
+            mockProjectFaultHandlerService,
             mockProjectThreadingService);
 
         provider.LaunchTargetsProviders.Add(_mockWebProvider.Object); // Use web provider instead
@@ -150,8 +152,9 @@ public async Task LaunchWithProfileAsync_WhenNotProjectCommand_DoesNotCreateHotR
     public void OnComplete_WhenHrIsErrorCode_ThrowsException()
     {
         // Arrange
-        var mockProjectThreadingService = IProjectThreadingServiceFactory.Create();
         var mockTargetsProvider = Mock.Of<IDebugProfileLaunchTargetsProvider>();
+        var mockProjectFaultHandlerService = IProjectFaultHandlerServiceFactory.Create();
+        var mockUnconfiguredProject = UnconfiguredProjectFactory.Create();
         var profile = new LaunchProfile("TestProfile", "Project");
         var launchOptions = DebugLaunchOptions.NoDebug;
 
@@ -162,11 +165,12 @@ public void OnComplete_WhenHrIsErrorCode_ThrowsException()
 
         var callback = Activator.CreateInstance(
             launchCompleteCallbackType,
-            mockProjectThreadingService,
             launchOptions,
             mockTargetsProvider,
             profile,
-            (IReadOnlyList<IDebugLaunchSettings>)[]);
+            (IReadOnlyList<IDebugLaunchSettings>)[],
+            mockProjectFaultHandlerService,
+            mockUnconfiguredProject);
 
         // Act & Assert
         var onCompleteMethod = launchCompleteCallbackType.GetMethod("OnComplete");
@@ -186,8 +190,9 @@ public void OnComplete_WhenHrIsErrorCode_ThrowsException()
     public void OnComplete_WhenHrIsSuccess_DoesNotThrowException()
     {
         // Arrange
-        var mockProjectThreadingService = IProjectThreadingServiceFactory.Create();
         var mockTargetsProvider = Mock.Of<IDebugProfileLaunchTargetsProvider>();
+        var mockProjectFaultHandlerService = IProjectFaultHandlerServiceFactory.Create();
+        var mockUnconfiguredProject = UnconfiguredProjectFactory.Create();
         var profile = new LaunchProfile("TestProfile", "Project");
         var launchOptions = DebugLaunchOptions.NoDebug;
 
@@ -198,11 +203,12 @@ public void OnComplete_WhenHrIsSuccess_DoesNotThrowException()
 
         var callback = Activator.CreateInstance(
             launchCompleteCallbackType,
-            mockProjectThreadingService,
             launchOptions,
             mockTargetsProvider,
             profile,
-            (IReadOnlyList<IDebugLaunchSettings>)[]);
+            (IReadOnlyList<IDebugLaunchSettings>)[],
+            mockProjectFaultHandlerService,
+            mockUnconfiguredProject);
 
         // Act & Assert
         var onCompleteMethod = launchCompleteCallbackType.GetMethod("OnComplete");
@@ -217,7 +223,7 @@ public void OnComplete_WhenHrIsSuccess_DoesNotThrowException()
 
     private LaunchProfilesDebugLaunchProvider CreateInstance()
     {
-        var provider = new LaunchProfilesDebugLaunchProvider(_configuredProjectMoq.Object, _launchSettingsProviderMoq.Object, vsDebuggerService: null!);
+        var provider = new LaunchProfilesDebugLaunchProvider(_configuredProjectMoq.Object, _launchSettingsProviderMoq.Object, vsDebuggerService: null!, projectFaultHandlerService: null!);
 
         provider.LaunchTargetsProviders.Add(_mockWebProvider.Object);
         provider.LaunchTargetsProviders.Add(_mockDockerProvider.Object);