import toDate from "../toDate/index.js"; import requiredArgs from "../_lib/requiredArgs/index.js"; /** * @name isLeapYear * @category Year Helpers * @summary Is the given date in the leap year? * * @description * Is the given date in the leap year? * * @param {Date|Number} date - the date to check * @returns {Boolean} the date is in the leap year * @throws {TypeError} 1 argument required * * @example * // Is 1 September 2012 in the leap year? * const result = isLeapYear(new Date(2012, 8, 1)) * //=> true */ export default function isLeapYear(dirtyDate) { requiredArgs(1, arguments); var date = toDate(dirtyDate); var year = date.getFullYear(); return year % 400 === 0 || year % 4 === 0 && year % 100 !== 0; }