import { toDate } from "./toDate.mjs"; /** * @name lastDayOfDecade * @category Decade Helpers * @summary Return the last day of a decade for the given date. * * @description * Return the last day of a decade for the given date. * * @typeParam DateType - The `Date` type, the function operates on. Gets inferred from passed arguments. Allows to use extensions like [`UTCDate`](https://github.com/date-fns/utc). * * @param date - The original date * * @returns The last day of a decade * * @example * // The last day of a decade for 21 December 2012 21:12:00: * const result = lastDayOfDecade(new Date(2012, 11, 21, 21, 12, 00)) * //=> Wed Dec 31 2019 00:00:00 */ export function lastDayOfDecade(date) { // TODO: Switch to more technical definition in of decades that start with 1 // end with 0. I.e. 2001-2010 instead of current 2000-2009. It's a breaking // change, so it can only be done in 4.0. const _date = toDate(date); const year = _date.getFullYear(); const decade = 9 + Math.floor(year / 10) * 10; _date.setFullYear(decade + 1, 0, 0); _date.setHours(0, 0, 0, 0); return _date; } // Fallback for modularized imports: export default lastDayOfDecade;