Try canceling previous code action requests on re-trigger

Fixes #49884

src/vs/editor/contrib/codeAction/codeAction.ts

@@ -5,7 +5,7 @@
 
 import { isFalsyOrEmpty, mergeSort, flatten } from 'vs/base/common/arrays';
 import { asWinJsPromise } from 'vs/base/common/async';
-import { illegalArgument, onUnexpectedExternalError } from 'vs/base/common/errors';
+import { illegalArgument, onUnexpectedExternalError, isPromiseCanceledError } from 'vs/base/common/errors';
 import URI from 'vs/base/common/uri';
 import { TPromise } from 'vs/base/common/winjs.base';
 import { registerLanguageCommand } from 'vs/editor/browser/editorExtensions';
@@ -28,6 +28,10 @@ export function getCodeActions(model: ITextModel, rangeOrSelection: Range | Sele
 			}
 			return providedCodeActions.filter(action => isValidAction(filter, action));
 		}, (err): CodeAction[] => {
+			if (isPromiseCanceledError(err)) {
+				throw err;
+			}
+
 			onUnexpectedExternalError(err);
 			return [];
 		});

src/vs/editor/contrib/codeAction/codeActionCommands.ts

@@ -46,6 +46,8 @@ export class QuickFixController implements IEditorContribution {
 	private _lightBulbWidget: LightBulbWidget;
 	private _disposables: IDisposable[] = [];
 
+	private _activeRequest: TPromise<CodeAction[]> | undefined;
+
 	constructor(editor: ICodeEditor,
 		@IMarkerService markerService: IMarkerService,
 		@IContextKeyService contextKeyService: IContextKeyService,
@@ -76,6 +78,15 @@ export class QuickFixController implements IEditorContribution {
 	}
 
 	private _onCodeActionsEvent(e: CodeActionsComputeEvent): void {
+		if (this._activeRequest) {
+			this._activeRequest.cancel();
+			this._activeRequest = undefined;
+		}
+
+		if (e && e.actions) {
+			this._activeRequest = e.actions;
+		}
+
 		if (e && e.trigger.filter && e.trigger.filter.kind) {
 			// Triggered for specific scope
 			// Apply if we only have one action or requested autoApply, otherwise show menu