var getISOYear = require('../get_iso_year/index.js') var startOfISOWeek = require('../start_of_iso_week/index.js') /** * @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 * * @param {Date|String|Number} date - the original date * @returns {Date} the end of an ISO week-numbering year * * @example * // The end of an ISO week-numbering year for 2 July 2005: * var result = endOfISOYear(new Date(2005, 6, 2)) * //=> Sun Jan 01 2006 23:59:59.999 */ function endOfISOYear (dirtyDate) { var year = getISOYear(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 } module.exports = endOfISOYear