timepiece/node_modules/date-fns/lastDayOfISOWeekYear.mjs

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2024-05-14 14:54:12 +00:00
import { getISOWeekYear } from "./getISOWeekYear.mjs";
import { startOfISOWeek } from "./startOfISOWeek.mjs";
import { constructFrom } from "./constructFrom.mjs";
/**
* @name lastDayOfISOWeekYear
* @category ISO Week-Numbering Year Helpers
* @summary Return the last day of an ISO week-numbering year for the given date.
*
* @description
* Return the last day 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
*
* @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 end of an ISO week-numbering year
*
* @example
* // The last day of an ISO week-numbering year for 2 July 2005:
* const result = lastDayOfISOWeekYear(new Date(2005, 6, 2))
* //=> Sun Jan 01 2006 00:00:00
*/
export function lastDayOfISOWeekYear(date) {
const year = getISOWeekYear(date);
const fourthOfJanuary = constructFrom(date, 0);
fourthOfJanuary.setFullYear(year + 1, 0, 4);
fourthOfJanuary.setHours(0, 0, 0, 0);
const _date = startOfISOWeek(fourthOfJanuary);
_date.setDate(_date.getDate() - 1);
return _date;
}
// Fallback for modularized imports:
export default lastDayOfISOWeekYear;