// Copyright (c) 2023 Ecma International. All rights reserved. // This code is governed by the BSD license found in the LICENSE file. /*--- esid: sec-map.groupby description: Map.groupBy returns a Map instance info: | Map.groupBy ( items, callbackfn ) ... 2. Let map be ! Construct(%Map%). ... 4. Return map. ... features: [array-grouping, Map] ---*/ const array = [1, 2, 3]; const map = Map.groupBy(array, function (i) { return i % 2 === 0 ? 'even' : 'odd'; }); assert.sameValue(map instanceof Map, true);