// Copyright 2018 the V8 project authors. All rights reserved.// Use of this source code is governed by a BSD-style license that can be// found in the LICENSE file.varlocales=["tlh","id","en"];varreferenceRelativeTimeFormat=newIntl.RelativeTimeFormat(locales);varreferenceFormatted=referenceRelativeTimeFormat.format(3,"day");classMyFormatextendsIntl.RelativeTimeFormat{constructor(locales,options){super(locales,options);// could initialize MyRelativeTimeFormat properties}// could add methods to MyRelativeTimeFormat.prototype}varformat=newMyFormat(locales);varactual=format.format(3,"day");assertEquals(actual,referenceFormatted);