hugoWebsite/node_modules/date-fns/differenceInCalendarISOWeeks/index.js

53 lines
1.9 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = differenceInCalendarISOWeeks;
var _index = _interopRequireDefault(require("../_lib/getTimezoneOffsetInMilliseconds/index.js"));
var _index2 = _interopRequireDefault(require("../startOfISOWeek/index.js"));
var _index3 = _interopRequireDefault(require("../_lib/requiredArgs/index.js"));
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
var MILLISECONDS_IN_WEEK = 604800000;
/**
* @name differenceInCalendarISOWeeks
* @category ISO Week Helpers
* @summary Get the number of calendar ISO weeks between the given dates.
*
* @description
* Get the number of calendar ISO weeks between the given dates.
*
* ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
*
* @param {Date|Number} dateLeft - the later date
* @param {Date|Number} dateRight - the earlier date
* @returns {Number} the number of calendar ISO weeks
* @throws {TypeError} 2 arguments required
*
* @example
* // How many calendar ISO weeks are between 6 July 2014 and 21 July 2014?
* const result = differenceInCalendarISOWeeks(
* new Date(2014, 6, 21),
* new Date(2014, 6, 6)
* )
* //=> 3
*/
function differenceInCalendarISOWeeks(dirtyDateLeft, dirtyDateRight) {
(0, _index3.default)(2, arguments);
var startOfISOWeekLeft = (0, _index2.default)(dirtyDateLeft);
var startOfISOWeekRight = (0, _index2.default)(dirtyDateRight);
var timestampLeft = startOfISOWeekLeft.getTime() - (0, _index.default)(startOfISOWeekLeft);
var timestampRight = startOfISOWeekRight.getTime() - (0, _index.default)(startOfISOWeekRight); // Round the number of days to the nearest integer
// because the number of milliseconds in a week is not constant
// (e.g. it's different in the week of the daylight saving time clock shift)
return Math.round((timestampLeft - timestampRight) / MILLISECONDS_IN_WEEK);
}
module.exports = exports.default;