Synchronizes in-editor scrolling back to virtual list scrolling. (microsoft#205959)

Fixes revealing issues.

Author: hediet

src/vs/editor/browser/widget/multiDiffEditorWidget/diffEditorItemTemplate.ts

@@ -24,6 +24,7 @@ import { createActionViewItem } from 'vs/platform/actions/browser/menuEntryActio
 export class TemplateData implements IObjectData {
 	constructor(
 		public readonly viewModel: DocumentDiffItemViewModel,
+		public readonly deltaScrollVertical: (delta: number) => void,
 	) { }
 
 
@@ -116,15 +117,15 @@ export class DiffEditorItemTemplate extends Disposable implements IPooledObject<
 			this._elements.editor.style.display = this._collapsed.read(reader) ? 'none' : 'block';
 		}));
 
-		this.editor.getModifiedEditor().onDidLayoutChange(e => {
+		this._register(this.editor.getModifiedEditor().onDidLayoutChange(e => {
 			const width = this.editor.getModifiedEditor().getLayoutInfo().contentWidth;
 			this._modifiedWidth.set(width, undefined);
-		});
+		}));
 
-		this.editor.getOriginalEditor().onDidLayoutChange(e => {
+		this._register(this.editor.getOriginalEditor().onDidLayoutChange(e => {
 			const width = this.editor.getOriginalEditor().getLayoutInfo().contentWidth;
 			this._originalWidth.set(width, undefined);
-		});
+		}));
 
 		this._register(this.editor.onDidContentSizeChange(e => {
 			globalTransaction(tx => {
@@ -134,6 +135,18 @@ export class DiffEditorItemTemplate extends Disposable implements IPooledObject<
 			});
 		}));
 
+		this._register(this.editor.getOriginalEditor().onDidScrollChange(e => {
+			if (this._isSettingScrollTop) {
+				return;
+			}
+
+			if (!e.scrollTopChanged || !this._data) {
+				return;
+			}
+			const delta = e.scrollTop - this._lastScrollTop;
+			this._data.deltaScrollVertical(delta);
+		}));
+
 		this._register(autorun(reader => {
 			const isFocused = this.isFocused.read(reader);
 			this._elements.root.classList.toggle('focused', isFocused);
@@ -162,7 +175,10 @@ export class DiffEditorItemTemplate extends Disposable implements IPooledObject<
 
 	private readonly _dataStore = new DisposableStore();
 
+	private _data: TemplateData | undefined;
+
 	public setData(data: TemplateData): void {
+		this._data = data;
 		function updateOptions(options: IDiffEditorOptions): IDiffEditorOptions {
 			return {
 				...options,
@@ -222,6 +238,9 @@ export class DiffEditorItemTemplate extends Disposable implements IPooledObject<
 
 	private readonly _headerHeight = /*this._elements.header.clientHeight*/ 48;
 
+	private _lastScrollTop = -1;
+	private _isSettingScrollTop = false;
+
 	public render(verticalRange: OffsetRange, width: number, editorScroll: number, viewPort: OffsetRange): void {
 		this._elements.root.style.visibility = 'visible';
 		this._elements.root.style.top = `${verticalRange.start}px`;
@@ -240,7 +259,13 @@ export class DiffEditorItemTemplate extends Disposable implements IPooledObject<
 				height: verticalRange.length - this._outerEditorHeight,
 			});
 		});
-		this.editor.getOriginalEditor().setScrollTop(editorScroll);
+		try {
+			this._isSettingScrollTop = true;
+			this._lastScrollTop = editorScroll;
+			this.editor.getOriginalEditor().setScrollTop(editorScroll);
+		} finally {
+			this._isSettingScrollTop = false;
+		}
 
 		this._elements.header.classList.toggle('shadow', delta > 0 || editorScroll > 0);
 		this._elements.header.classList.toggle('collapsed', delta === maxDelta);

src/vs/editor/browser/widget/multiDiffEditorWidget/multiDiffEditorWidgetImpl.ts

@@ -76,7 +76,9 @@ export class MultiDiffEditorWidgetImpl extends Disposable {
 			}
 			const items = vm.items.read(reader);
 			return items.map(d => {
-				const item = store.add(new VirtualizedViewItem(d, this._objectPool, this.scrollLeft));
+				const item = store.add(new VirtualizedViewItem(d, this._objectPool, this.scrollLeft, delta => {
+					this._scrollableElement.setScrollPosition({ scrollTop: this._scrollableElement.getScrollPosition().scrollTop + delta });
+				}));
 				const data = this._lastDocStates?.[item.getKey()];
 				if (data) {
 					transaction(tx => {
@@ -344,6 +346,7 @@ class VirtualizedViewItem extends Disposable {
 		public readonly viewModel: DocumentDiffItemViewModel,
 		private readonly _objectPool: ObjectPool<TemplateData, DiffEditorItemTemplate>,
 		private readonly _scrollLeft: IObservable<number>,
+		private readonly _deltaScrollVertical: (delta: number) => void,
 	) {
 		super();
 
@@ -434,7 +437,7 @@ class VirtualizedViewItem extends Disposable {
 
 		let ref = this._templateRef.get();
 		if (!ref) {
-			ref = this._objectPool.getUnusedObj(new TemplateData(this.viewModel));
+			ref = this._objectPool.getUnusedObj(new TemplateData(this.viewModel, this._deltaScrollVertical));
 			this._templateRef.set(ref, undefined);
 
 			const selections = this.viewModel.lastTemplateData.get().selections;