src/vs/base/browser/ui/tree/objectTreeModel.ts/ObjectTreeModel/compare
class ObjectTreeModel:	constructor(
		private user: string,
		list: IList<ITreeNode<T, TFilterData>>,
		options: IObjectTreeModelOptions<T, TFilterData> = {}
	) {
		this.model = new IndexTreeModel(user, list, null, options);
		this.onDidSplice = this.model.onDidSplice;
		this.onDidChangeCollapseState = this.model.onDidChangeCollapseState as Event<ICollapseStateChangeEvent<T, TFilterData>>;
		this.onDidChangeRenderNodeCount = this.model.onDidChangeRenderNodeCount as Event<ITreeNode<T, TFilterData>>;

		if (options.sorter) {
			this.sorter = {
				compare(a, b) {
					return options.sorter!.compare(a.element, b.element);
				}
			};
		}

		this.identityProvider = options.identityProvider;
	}