Revert "async data tree: use proxies instead"

This reverts commit 492def26.

src/vs/base/browser/ui/tree/asyncDataTree.ts

@@ -66,32 +66,20 @@ interface IDataTreeListTemplateData<T> {
 	templateData: T;
 }
 
-class NodeMapper<TInput, T, TFilterData> {
-
-	private map = new WeakMap<ITreeNode<IAsyncDataTreeNode<TInput, T> | null, TFilterData>, ITreeNode<TInput | T, TFilterData>>();
-
-	mapNode(node: ITreeNode<IAsyncDataTreeNode<TInput, T> | null, TFilterData>): ITreeNode<TInput | T, TFilterData> {
-		const that = this;
-		let result = this.map.get(node);
-
-		if (!result) {
-			result = new Proxy(node, {
-				get(obj, prop) {
-					if (prop === 'element') {
-						return node.element!.element;
-					} else if (prop === 'children') {
-						return node.children.map(child => that.mapNode(child));
-					}
-
-					return (obj as any)[prop];
-				}
-			}) as unknown as ITreeNode<TInput | T, TFilterData>;
-
-			this.map.set(node, result);
-		}
-
-		return result;
-	}
+class AsyncDataTreeNodeWrapper<TInput, T, TFilterData> implements ITreeNode<TInput | T, TFilterData> {
+
+	get element(): T { return this.node.element!.element as T; }
+	get parent(): ITreeNode<T, TFilterData> | undefined { return this.node.parent && new AsyncDataTreeNodeWrapper(this.node.parent); }
+	get children(): ITreeNode<T, TFilterData>[] { return this.node.children.map(node => new AsyncDataTreeNodeWrapper(node)); }
+	get depth(): number { return this.node.depth; }
+	get visibleChildrenCount(): number { return this.node.visibleChildrenCount; }
+	get visibleChildIndex(): number { return this.node.visibleChildIndex; }
+	get collapsible(): boolean { return this.node.collapsible; }
+	get collapsed(): boolean { return this.node.collapsed; }
+	get visible(): boolean { return this.node.visible; }
+	get filterData(): TFilterData | undefined { return this.node.filterData; }
+
+	constructor(private node: ITreeNode<IAsyncDataTreeNode<TInput, T> | null, TFilterData>) { }
 }
 
 class DataTreeRenderer<TInput, T, TFilterData, TTemplateData> implements ITreeRenderer<IAsyncDataTreeNode<TInput, T>, TFilterData, IDataTreeListTemplateData<TTemplateData>> {
@@ -102,7 +90,6 @@ class DataTreeRenderer<TInput, T, TFilterData, TTemplateData> implements ITreeRe
 
 	constructor(
 		private renderer: ITreeRenderer<T, TFilterData, TTemplateData>,
-		private nodeMapper: NodeMapper<TInput, T, TFilterData>,
 		readonly onDidChangeTwistieState: Event<IAsyncDataTreeNode<TInput, T>>
 	) {
 		this.templateId = renderer.templateId;
@@ -114,7 +101,7 @@ class DataTreeRenderer<TInput, T, TFilterData, TTemplateData> implements ITreeRe
 	}
 
 	renderElement(node: ITreeNode<IAsyncDataTreeNode<TInput, T>, TFilterData>, index: number, templateData: IDataTreeListTemplateData<TTemplateData>, height: number | undefined): void {
-		this.renderer.renderElement(this.nodeMapper.mapNode(node) as ITreeNode<T, TFilterData>, index, templateData.templateData, height);
+		this.renderer.renderElement(new AsyncDataTreeNodeWrapper(node), index, templateData.templateData, height);
 	}
 
 	renderTwistie(element: IAsyncDataTreeNode<TInput, T>, twistieElement: HTMLElement): boolean {
@@ -124,7 +111,7 @@ class DataTreeRenderer<TInput, T, TFilterData, TTemplateData> implements ITreeRe
 
 	disposeElement(node: ITreeNode<IAsyncDataTreeNode<TInput, T>, TFilterData>, index: number, templateData: IDataTreeListTemplateData<TTemplateData>, height: number | undefined): void {
 		if (this.renderer.disposeElement) {
-			this.renderer.disposeElement(this.nodeMapper.mapNode(node) as ITreeNode<T, TFilterData>, index, templateData.templateData, height);
+			this.renderer.disposeElement(new AsyncDataTreeNodeWrapper(node), index, templateData.templateData, height);
 		}
 	}
 
@@ -319,8 +306,6 @@ export class AsyncDataTree<TInput, T, TFilterData = void> implements IDisposable
 	private readonly _onDidRender = new Emitter<void>();
 	private readonly _onDidChangeNodeSlowState = new Emitter<IAsyncDataTreeNode<TInput, T>>();
 
-	private readonly nodeMapper = new NodeMapper<TInput, T, TFilterData>();
-
 	protected readonly disposables: IDisposable[] = [];
 
 	get onDidScroll(): Event<ScrollEvent> { return this.tree.onDidScroll; }
@@ -367,7 +352,7 @@ export class AsyncDataTree<TInput, T, TFilterData = void> implements IDisposable
 		this.collapseByDefault = options.collapseByDefault;
 
 		const objectTreeDelegate = new ComposedTreeDelegate<TInput | T, IAsyncDataTreeNode<TInput, T>>(delegate);
-		const objectTreeRenderers = renderers.map(r => new DataTreeRenderer(r, this.nodeMapper, this._onDidChangeNodeSlowState.event));
+		const objectTreeRenderers = renderers.map(r => new DataTreeRenderer(r, this._onDidChangeNodeSlowState.event));
 		const objectTreeOptions = asObjectTreeOptions<TInput, T, TFilterData>(options) || {};
 
 		this.tree = new ObjectTree(user, container, objectTreeDelegate, objectTreeRenderers, objectTreeOptions);
@@ -525,7 +510,7 @@ export class AsyncDataTree<TInput, T, TFilterData = void> implements IDisposable
 	getNode(element: TInput | T = this.root.element): ITreeNode<TInput | T, TFilterData> {
 		const dataNode = this.getDataNode(element);
 		const node = this.tree.getNode(dataNode === this.root ? null : dataNode);
-		return this.nodeMapper.mapNode(node);
+		return new AsyncDataTreeNodeWrapper<TInput, T, TFilterData>(node);
 	}
 
 	collapse(element: T, recursive: boolean = false): boolean {