12345678910111213141516171819202122232425262728293031323334353637383940414243444546 |
- import { constructFrom } from "./constructFrom.js";
- import { getISOWeekYear } from "./getISOWeekYear.js";
- import { startOfISOWeek } from "./startOfISOWeek.js";
- /**
- * The {@link lastDayOfISOWeekYear} function options.
- */
- /**
- * @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).
- * @typeParam ResultDate - The result `Date` type, it is the type returned from the context function if it is passed, or inferred from the arguments.
- *
- * @param date - The original date
- * @param options - An object with options
- *
- * @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, options) {
- const year = getISOWeekYear(date, options);
- const fourthOfJanuary = constructFrom(options?.in || date, 0);
- fourthOfJanuary.setFullYear(year + 1, 0, 4);
- fourthOfJanuary.setHours(0, 0, 0, 0);
- const date_ = startOfISOWeek(fourthOfJanuary, options);
- date_.setDate(date_.getDate() - 1);
- return date_;
- }
- // Fallback for modularized imports:
- export default lastDayOfISOWeekYear;
|