timepiece/node_modules/date-fns/setISOWeekYear.mjs

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2024-05-14 14:54:12 +00:00
import { constructFrom } from "./constructFrom.mjs";
import { differenceInCalendarDays } from "./differenceInCalendarDays.mjs";
import { startOfISOWeekYear } from "./startOfISOWeekYear.mjs";
import { toDate } from "./toDate.mjs";
/**
* @name setISOWeekYear
* @category ISO Week-Numbering Year Helpers
* @summary Set the ISO week-numbering year to the given date.
*
* @description
* Set the ISO week-numbering year to the given date,
* saving the week number and the weekday number.
*
* 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 date to be changed
* @param weekYear - The ISO week-numbering year of the new date
*
* @returns The new date with the ISO week-numbering year set
*
* @example
* // Set ISO week-numbering year 2007 to 29 December 2008:
* const result = setISOWeekYear(new Date(2008, 11, 29), 2007)
* //=> Mon Jan 01 2007 00:00:00
*/
export function setISOWeekYear(date, weekYear) {
let _date = toDate(date);
const diff = differenceInCalendarDays(_date, startOfISOWeekYear(_date));
const fourthOfJanuary = constructFrom(date, 0);
fourthOfJanuary.setFullYear(weekYear, 0, 4);
fourthOfJanuary.setHours(0, 0, 0, 0);
_date = startOfISOWeekYear(fourthOfJanuary);
_date.setDate(_date.getDate() + diff);
return _date;
}
// Fallback for modularized imports:
export default setISOWeekYear;