@ -123,9 +123,8 @@ export class CustomTree extends Widget {
itemsCreator: (op, callback) => {
itemsCreator.apply(this, [
op,
items => {
const args = Array.prototype.slice.call(arguments, 0);
args[0] = this._formatItems(items);
(...args) => {
args[0] = this._formatItems(args[0]);
callback(...args);
}
]);