timepiece/node_modules/date-fns/startOfWeekYear.js

65 lines
2.3 KiB
JavaScript

"use strict";
exports.startOfWeekYear = startOfWeekYear;
var _index = require("./constructFrom.js");
var _index2 = require("./getWeekYear.js");
var _index3 = require("./startOfWeek.js");
var _index4 = require("./_lib/defaultOptions.js");
/**
* The {@link startOfWeekYear} function options.
*/
/**
* @name startOfWeekYear
* @category Week-Numbering Year Helpers
* @summary Return the start of a local week-numbering year for the given date.
*
* @description
* Return the start of a local week-numbering year.
* 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 original date
* @param options - An object with options
*
* @returns The start of a week-numbering year
*
* @example
* // The start of an a week-numbering year for 2 July 2005 with default settings:
* const result = startOfWeekYear(new Date(2005, 6, 2))
* //=> Sun Dec 26 2004 00:00:00
*
* @example
* // The start of a week-numbering year for 2 July 2005
* // if Monday is the first day of week
* // and 4 January is always in the first week of the year:
* const result = startOfWeekYear(new Date(2005, 6, 2), {
* weekStartsOn: 1,
* firstWeekContainsDate: 4
* })
* //=> Mon Jan 03 2005 00:00:00
*/
function startOfWeekYear(date, options) {
const defaultOptions = (0, _index4.getDefaultOptions)();
const firstWeekContainsDate =
options?.firstWeekContainsDate ??
options?.locale?.options?.firstWeekContainsDate ??
defaultOptions.firstWeekContainsDate ??
defaultOptions.locale?.options?.firstWeekContainsDate ??
1;
const year = (0, _index2.getWeekYear)(date, options);
const firstWeek = (0, _index.constructFrom)(date, 0);
firstWeek.setFullYear(year, 0, firstWeekContainsDate);
firstWeek.setHours(0, 0, 0, 0);
const _date = (0, _index3.startOfWeek)(firstWeek, options);
return _date;
}