list: prevent recursive splicing

fixes #39105

src/vs/base/browser/ui/list/listView.ts

@@ -70,6 +70,7 @@ export class ListView<T> implements ISpliceable<T>, IDisposable {
 	private gesture: Gesture;
 	private rowsContainer: HTMLElement;
 	private scrollableElement: ScrollableElement;
+	private splicing = false;
 	private disposables: IDisposable[];
 
 	constructor(
@@ -121,6 +122,20 @@ export class ListView<T> implements ISpliceable<T>, IDisposable {
 	}
 
 	splice(start: number, deleteCount: number, elements: T[] = []): T[] {
+		if (this.splicing) {
+			throw new Error('Can\'t run recursive splices.');
+		}
+
+		this.splicing = true;
+
+		try {
+			return this._splice(start, deleteCount, elements);
+		} finally {
+			this.splicing = false;
+		}
+	}
+
+	private _splice(start: number, deleteCount: number, elements: T[] = []): T[] {
 		const previousRenderRange = this.getRenderRange(this.lastRenderTop, this.lastRenderHeight);
 		const deleteRange = { start, end: start + deleteCount };
 		const removeRange = intersect(previousRenderRange, deleteRange);