CmdPal: Fallback ranking and global results

.github/actions/spell-check/expect.txt

@@ -1182,6 +1182,7 @@ openas
 opencode
 OPENFILENAME
 opensource
+openurl
 openxmlformats
 OPTIMIZEFORINVOKE
 ORPHANEDDIALOGTITLE

src/modules/cmdpal/Core/Microsoft.CmdPal.Core.Common/Helpers/SupersedingAsyncGate.cs

@@ -2,10 +2,6 @@
 // The Microsoft Corporation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
-using System.Threading;
-using System.Threading.Tasks;
-
 namespace Microsoft.CmdPal.Core.Common.Helpers;
 
 /// <summary>
@@ -36,24 +32,36 @@ public SupersedingAsyncGate(Func<CancellationToken, Task> action)
     public async Task ExecuteAsync(CancellationToken cancellationToken = default)
     {
         TaskCompletionSource<bool> tcs;
+        var startWorker = false;
 
         lock (_lock)
         {
+            // Cancel the currently running iteration (if any) before replacing its TCS.
             _currentCancellationSource?.Cancel();
+
+            // Mark prior waiter as superseded. Fault (not cancel) so callers can distinguish.
             _currentTcs?.TrySetException(new OperationCanceledException("Superseded by newer call"));
 
-            tcs = new();
+            // IMPORTANT: RunContinuationsAsynchronously prevents continuations from running
+            // inside this lock, avoiding reentrancy / potential deadlocks.
+            tcs = new(TaskCreationOptions.RunContinuationsAsynchronously);
             _currentTcs = tcs;
             _callId++;
 
-            var shouldStartExecution = _executingTask is null;
-            if (shouldStartExecution)
+            if (_executingTask is null)
             {
-                _executingTask = Task.Run(ExecuteLoop, CancellationToken.None);
+                startWorker = true;
             }
         }
 
-        await using var ctr = cancellationToken.Register(() => tcs.TrySetCanceled(cancellationToken));
+        // Start worker outside lock to avoid holding lock while scheduling.
+        if (startWorker)
+        {
+            // Fire-and-forget loop; all state transitions guarded by _lock.
+            _executingTask = Task.Run(ExecuteLoop, cancellationToken);
+        }
+
+        using var ctr = cancellationToken.Register(() => tcs.TrySetCanceled(cancellationToken));
         await tcs.Task;
     }
 

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/CommandProviderWrapper.cs

@@ -188,11 +188,12 @@ private void InitializeCommands(ICommandItem[] commands, IFallbackCommandItem[]
         Func<ICommandItem?, bool, TopLevelViewModel> makeAndAdd = (ICommandItem? i, bool fallback) =>
         {
             CommandItemViewModel commandItemViewModel = new(new(i), pageContext);
-            TopLevelViewModel topLevelViewModel = new(commandItemViewModel, fallback, ExtensionHost, ProviderId, settings, providerSettings, serviceProvider);
+            TopLevelViewModel topLevelViewModel = new(commandItemViewModel, fallback, ExtensionHost, ProviderId, settings, providerSettings, serviceProvider, i);
             topLevelViewModel.InitializeProperties();
 
             return topLevelViewModel;
         };
+
         if (commands is not null)
         {
             TopLevelItems = commands

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/Commands/BuiltInsCommandProvider.cs

@@ -2,7 +2,6 @@
 // The Microsoft Corporation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using Microsoft.CmdPal.Core.ViewModels.Messages;
 using Microsoft.CommandPalette.Extensions;
 using Microsoft.CommandPalette.Extensions.Toolkit;
 
@@ -27,9 +26,9 @@ public override ICommandItem[] TopLevelCommands() =>
 
     public override IFallbackCommandItem[] FallbackCommands() =>
         [
-            new FallbackCommandItem(quitCommand, displayTitle: Properties.Resources.builtin_quit_subtitle) { Subtitle = Properties.Resources.builtin_quit_subtitle },
+            new FallbackCommandItem(quitCommand, displayTitle: Properties.Resources.builtin_quit_subtitle, quitCommand.Id) { Subtitle = Properties.Resources.builtin_quit_subtitle },
             _fallbackReloadItem,
-            _fallbackLogItem,
+            _fallbackLogItem
         ];
 
     public BuiltInsCommandProvider()

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/Commands/FallbackLogItem.cs

@@ -13,8 +13,10 @@ internal sealed partial class FallbackLogItem : FallbackCommandItem
 {
     private readonly LogMessagesPage _logMessagesPage;
 
+    private const string _id = "com.microsoft.cmdpal.log";
+
     public FallbackLogItem()
-        : base(new LogMessagesPage() { Id = "com.microsoft.cmdpal.log" }, Resources.builtin_log_subtitle)
+        : base(new LogMessagesPage() { Id = _id }, Resources.builtin_log_subtitle, _id)
     {
         _logMessagesPage = (LogMessagesPage)Command!;
         Title = string.Empty;

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/Commands/FallbackReloadItem.cs

@@ -2,7 +2,6 @@
 // The Microsoft Corporation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
 using Microsoft.CommandPalette.Extensions.Toolkit;
 
 namespace Microsoft.CmdPal.UI.ViewModels.BuiltinCommands;
@@ -11,10 +10,13 @@ internal sealed partial class FallbackReloadItem : FallbackCommandItem
 {
     private readonly ReloadExtensionsCommand _reloadCommand;
 
+    private const string _id = "com.microsoft.cmdpal.reload";
+
     public FallbackReloadItem()
         : base(
-            new ReloadExtensionsCommand() { Id = "com.microsoft.cmdpal.reload" },
-            Properties.Resources.builtin_reload_display_title)
+            new ReloadExtensionsCommand() { Id = _id },
+            Properties.Resources.builtin_reload_display_title,
+            _id)
     {
         _reloadCommand = (ReloadExtensionsCommand)Command!;
         Title = string.Empty;