123456789101112131415161718192021222324252627282930313233343536373839404142 |
- "use strict";
- var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault").default;
- Object.defineProperty(exports, "__esModule", {
- value: true
- });
- exports.default = getISOWeeksInYear;
- var _index = _interopRequireDefault(require("../startOfISOWeekYear/index.js"));
- var _index2 = _interopRequireDefault(require("../addWeeks/index.js"));
- var _index3 = _interopRequireDefault(require("../_lib/requiredArgs/index.js"));
- var MILLISECONDS_IN_WEEK = 604800000;
- /**
- * @name getISOWeeksInYear
- * @category ISO Week-Numbering Year Helpers
- * @summary Get the number of weeks in an ISO week-numbering year of the given date.
- *
- * @description
- * Get the number of weeks in an ISO week-numbering year of the given date.
- *
- * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date
- *
- * @param {Date|Number} date - the given date
- * @returns {Number} the number of ISO weeks in a year
- * @throws {TypeError} 1 argument required
- *
- * @example
- * // How many weeks are in ISO week-numbering year 2015?
- * const result = getISOWeeksInYear(new Date(2015, 1, 11))
- * //=> 53
- */
- function getISOWeeksInYear(dirtyDate) {
- (0, _index3.default)(1, arguments);
- var thisYear = (0, _index.default)(dirtyDate);
- var nextYear = (0, _index.default)((0, _index2.default)(thisYear, 60));
- var diff = nextYear.valueOf() - thisYear.valueOf();
- // Round the number of weeks 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(diff / MILLISECONDS_IN_WEEK);
- }
- module.exports = exports.default;
|