timepiece/node_modules/date-fns/setWeekYear.mjs

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2024-05-14 14:54:12 +00:00
import { constructFrom } from "./constructFrom.mjs";
import { differenceInCalendarDays } from "./differenceInCalendarDays.mjs";
import { startOfWeekYear } from "./startOfWeekYear.mjs";
import { toDate } from "./toDate.mjs";
import { getDefaultOptions } from "./_lib/defaultOptions.mjs";
/**
* The {@link setWeekYear} function options.
*/
/**
* @name setWeekYear
* @category Week-Numbering Year Helpers
* @summary Set the local week-numbering year to the given date.
*
* @description
* Set the local week-numbering year to the given date,
* saving the week number and the weekday number.
* The exact calculation depends on the values of
* `options.weekStartsOn` (which is the index of the first day of the week)
* and `options.firstWeekContainsDate` (which is the day of January, which is always in
* the first week of the week-numbering year)
*
* Week numbering: https://en.wikipedia.org/wiki/Week#The_ISO_week_date_system
*
* @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 local week-numbering year of the new date
* @param options - An object with options
*
* @returns The new date with the local week-numbering year set
*
* @example
* // Set the local week-numbering year 2004 to 2 January 2010 with default options:
* const result = setWeekYear(new Date(2010, 0, 2), 2004)
* //=> Sat Jan 03 2004 00:00:00
*
* @example
* // Set the local week-numbering year 2004 to 2 January 2010,
* // if Monday is the first day of week
* // and 4 January is always in the first week of the year:
* const result = setWeekYear(new Date(2010, 0, 2), 2004, {
* weekStartsOn: 1,
* firstWeekContainsDate: 4
* })
* //=> Sat Jan 01 2005 00:00:00
*/
export function setWeekYear(date, weekYear, options) {
const defaultOptions = getDefaultOptions();
const firstWeekContainsDate =
options?.firstWeekContainsDate ??
options?.locale?.options?.firstWeekContainsDate ??
defaultOptions.firstWeekContainsDate ??
defaultOptions.locale?.options?.firstWeekContainsDate ??
1;
let _date = toDate(date);
const diff = differenceInCalendarDays(_date, startOfWeekYear(_date, options));
const firstWeek = constructFrom(date, 0);
firstWeek.setFullYear(weekYear, 0, firstWeekContainsDate);
firstWeek.setHours(0, 0, 0, 0);
_date = startOfWeekYear(firstWeek, options);
_date.setDate(_date.getDate() + diff);
return _date;
}
// Fallback for modularized imports:
export default setWeekYear;