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import toDate from '../toDate/index.ts'import startOfISOWeek from '../startOfISOWeek/index.ts'import startOfISOWeekYear from '../startOfISOWeekYear/index.ts'import requiredArgs from '../_lib/requiredArgs/index.ts'
const MILLISECONDS_IN_WEEK = 604800000
/** * @name getISOWeek * @category ISO Week Helpers * @summary Get the ISO week of the given date. * * @description * Get the ISO week of the given date. * * ISO week-numbering year: http://en.wikipedia.org/wiki/ISO_week_date * * ### v2.0.0 breaking changes: * * - [Changes that are common for the whole library](https://github.com/date-fns/date-fns/blob/master/docs/upgradeGuide.md#Common-Changes). * * @param {Date|Number} date - the given date * @returns {Number} the ISO week * @throws {TypeError} 1 argument required * * @example * // Which week of the ISO-week numbering year is 2 January 2005? * const result = getISOWeek(new Date(2005, 0, 2)) * //=> 53 */export default function getISOWeek(dirtyDate: Date | number): number {  requiredArgs(1, arguments)
  const date = toDate(dirtyDate)  const diff = startOfISOWeek(date).getTime() - startOfISOWeekYear(date).getTime()
  // 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(diff / MILLISECONDS_IN_WEEK) + 1}