import getISOWeekYear from '../getISOWeekYear/index.js'; import startOfISOWeek from '../startOfISOWeek/index.js'; /** * @name endOfISOWeekYear * @category ISO Week-Numbering Year Helpers * @summary Return the end of an ISO week-numbering year for the given date. * * @description * Return the end of an ISO week-numbering year, * which always starts 3 days before the year's first Thursday. * The result will be in the local timezone. * * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date * * ### v2.0.0 breaking changes: * * - [Changes that are common for the whole library](https://github.com/date-fns/date-fns/blob/master/docs/upgradeGuide.md#Common-Changes). * * - The function was renamed from `endOfISOYear` to `endOfISOWeekYear`. * "ISO week year" is short for [ISO week-numbering year](https://en.wikipedia.org/wiki/ISO_week_date). * This change makes the name consistent with * locale-dependent week-numbering year helpers, e.g., `addWeekYears`. * * @param {Date|Number} date - the original date * @returns {Date} the end of an ISO week-numbering year * @throws {TypeError} 1 argument required * * @example * // The end of an ISO week-numbering year for 2 July 2005: * var result = endOfISOWeekYear(new Date(2005, 6, 2)) * //=> Sun Jan 01 2006 23:59:59.999 */ export default function endOfISOWeekYear(dirtyDate) { if (arguments.length < 1) { throw new TypeError('1 argument required, but only ' + arguments.length + ' present'); } var year = getISOWeekYear(dirtyDate); var fourthOfJanuaryOfNextYear = new Date(0); fourthOfJanuaryOfNextYear.setFullYear(year + 1, 0, 4); fourthOfJanuaryOfNextYear.setHours(0, 0, 0, 0); var date = startOfISOWeek(fourthOfJanuaryOfNextYear); date.setMilliseconds(date.getMilliseconds() - 1); return date; }