Update to platform background work pattern to make porting to their impl easier (#78469)

Author: CyrusNajmabadi

src/EditorFeatures/CSharp/EventHookup/EventHookupCommandHandler_TabKeyCommand.cs

@@ -167,7 +167,7 @@ async Task<bool> TryExecuteCommandAsync()
             }
 
             // We're about to make an edit ourselves.  so disable the cancellation that happens on editing.
-            waitContext.CancelOnEdit = false;
+            using var _ = waitContext.SuppressAutoCancel();
 
             var workspace = document.Project.Solution.Workspace;
             if (!workspace.TryApplyChanges(solutionAndRenameSpan.Value.solution))

src/EditorFeatures/Core/BackgroundWorkIndicator/BackgroundWorkIndicatorContext.cs

@@ -296,5 +296,25 @@ public void RemoveScope(BackgroundWorkIndicatorScope scope)
         string IUIThreadOperationContext.Description => BuildData().description;
 
         bool IUIThreadOperationContext.AllowCancellation => true;
+
+        public IDisposable SuppressAutoCancel()
+        {
+            var disposer = new SuppressAutoCancelDisposable(this, this.CancelOnEdit, this.CancelOnFocusLost);
+            this.CancelOnEdit = false;
+            this.CancelOnFocusLost = false;
+            return disposer;
+        }
+    }
+
+    private sealed class SuppressAutoCancelDisposable(
+        BackgroundWorkIndicatorContext context,
+        bool originalCancelOnEdit,
+        bool originalCancelOnFocusLost) : IDisposable
+    {
+        public void Dispose()
+        {
+            context.CancelOnEdit = originalCancelOnEdit;
+            context.CancelOnFocusLost = originalCancelOnFocusLost;
+        }
     }
 }

src/EditorFeatures/Core/BackgroundWorkIndicator/IBackgroundWorkIndicatorContext.cs

@@ -2,23 +2,15 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
 using Microsoft.VisualStudio.Utilities;
 
 namespace Microsoft.CodeAnalysis.Editor.BackgroundWorkIndicator;
 
 internal interface IBackgroundWorkIndicatorContext : IUIThreadOperationContext
 {
     /// <summary>
-    /// Whether or not this context should cancel work if a navigation happens. Clients that use this indicator can 
-    /// have this behavior set to true (so that they cancel if the user edits themselves), but then set this to
-    /// false right before they edit themselves so that they do not self-cancel.
+    /// Allows clients to temporarily suppress auto cancel behaviors when they want to apply edits or navigate without canceling.
     /// </summary>
-    bool CancelOnEdit { get; set; }
-
-    /// <summary>
-    /// Whether or not this context should cancel work if the text view it is attached to loses focus. Clients that use
-    /// this indicator can have this behavior set to true (so that they cancel if the user navigates themselves), but
-    /// then set this to false right before they navigate themselves so that they do not self-cancel.
-    /// </summary>
-    bool CancelOnFocusLost { get; set; }
+    IDisposable SuppressAutoCancel();
 }

src/EditorFeatures/Core/ExtractMethod/ExtractMethodCommandHandler.cs

@@ -201,7 +201,8 @@ private void ApplyChange_OnUIThread(
         using var undoTransaction = _undoManager.GetTextBufferUndoManager(textBuffer).TextBufferUndoHistory.CreateTransaction("Extract Method");
 
         // We're about to make an edit ourselves.  so disable the cancellation that happens on editing.
-        waitContext.CancelOnEdit = false;
+        using var _ = waitContext.SuppressAutoCancel();
+
         textBuffer.ApplyChanges(changes);
 
         // apply changes

src/EditorFeatures/Core/GoToDefinition/GoToDefinitionCommandHandler.cs

@@ -16,6 +16,7 @@
 using Microsoft.CodeAnalysis.Shared.TestHooks;
 using Microsoft.CodeAnalysis.Text;
 using Microsoft.VisualStudio.Commanding;
+using Microsoft.VisualStudio.Language.Intellisense.Utilities;
 using Microsoft.VisualStudio.Text;
 using Microsoft.VisualStudio.Text.Editor.Commanding.Commands;
 using Microsoft.VisualStudio.Threading;
@@ -128,7 +129,8 @@ private async Task ExecuteAsynchronouslyAsync(
 
             // we're about to navigate.  so disable cancellation on focus-lost in our indicator so we don't end up
             // causing ourselves to self-cancel.
-            backgroundIndicator.CancelOnFocusLost = false;
+            using var _ = backgroundIndicator.SuppressAutoCancel();
+
             succeeded = definitionLocation != null && await definitionLocation.Location.TryNavigateToAsync(
                 _threadingContext, new NavigationOptions(PreferProvisionalTab: true, ActivateTab: true), cancellationToken).ConfigureAwait(false);
         }

src/EditorFeatures/Core/Organizing/OrganizeDocumentCommandHandler.cs

@@ -19,6 +19,7 @@
 using Microsoft.CodeAnalysis.Shared.TestHooks;
 using Microsoft.CodeAnalysis.Text;
 using Microsoft.VisualStudio.Commanding;
+using Microsoft.VisualStudio.Language.Intellisense.Utilities;
 using Microsoft.VisualStudio.Text;
 using Microsoft.VisualStudio.Text.Editor.Commanding;
 using Microsoft.VisualStudio.Threading;
@@ -152,7 +153,7 @@ private async Task ExecuteAsync(
         await _threadingContext.JoinableTaskFactory.SwitchToMainThreadAsync(cancellationToken);
 
         // We're about to make an edit ourselves.  so disable the cancellation that happens on editing.
-        backgroundWorkContext.CancelOnEdit = false;
+        using var _ = backgroundWorkContext.SuppressAutoCancel();
 
         commandArgs.SubjectBuffer.ApplyChanges(changes);
     }