Add Event.accumulate helper

Author: Tyriar

src/vs/base/common/event.ts

@@ -70,6 +70,23 @@ export namespace Event {
 		return debounce<unknown, void>(event, () => void 0, 0, undefined, undefined, disposable);
 	}
 
+	/**
+	 * Debounces an event, firing after some delay (default=0) with an array of all event original objects.
+	 *
+	 * *NOTE* that this function returns an `Event` and it MUST be called with a `DisposableStore` whenever the returned
+	 * event is accessible to "third parties", e.g the event is a public property. Otherwise a leaked listener on the
+	 * returned event causes this utility to leak a listener on the original event.
+	 */
+	export function accumulate<T>(event: Event<T>, delay: number = 0, disposable?: DisposableStore): Event<T[]> {
+		return Event.debounce<T, T[]>(event, (last, e) => {
+			if (!last) {
+				return [e];
+			}
+			last.push(e);
+			return last;
+		}, delay, undefined, undefined, disposable);
+	}
+
 	/**
 	 * Given an event, returns another event which only fires once.
 	 */

src/vs/workbench/browser/parts/editor/editorStatus.ts

@@ -683,13 +683,7 @@ export class EditorStatus extends Disposable implements IWorkbenchContribution {
 			}));
 
 			// Hook Listener for content changes
-			this.activeEditorListeners.add(Event.debounce<IModelContentChangedEvent, IModelContentChangedEvent[]>(activeCodeEditor.onDidChangeModelContent, (last, e) => {
-				if (!last) {
-					return [e];
-				}
-				last.push(e);
-				return last;
-			}, 0)(e => {
+			this.activeEditorListeners.add(Event.accumulate(activeCodeEditor.onDidChangeModelContent, this._store)(e => {
 				this.onEOLChange(activeCodeEditor);
 				this.currentProblemStatus.update(activeCodeEditor);