/* eslint-disable eslint-comments/no-unlimited-disable */ /* eslint-disable */ // @ts-nocheck import { addWeeks } from '../addWeeks/index.ts'; import { millisecondsInWeek } from '../constants/index.ts'; import { startOfISOWeekYear } from '../startOfISOWeekYear/index.ts'; import type { ContextOptions, DateArg } from '../types.ts'; /** * The {@link getISOWeeksInYear} function options. */ export interface GetISOWeeksInYearOptions extends ContextOptions {} /** * @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 - The given date * @param options - An object with options * * @returns The number of ISO weeks in a year * * @example * // How many weeks are in ISO week-numbering year 2015? * const result = getISOWeeksInYear(new Date(2015, 1, 11)) * //=> 53 */ export function getISOWeeksInYear(date: DateArg & {}, options?: GetISOWeeksInYearOptions | undefined): number { const thisYear = startOfISOWeekYear(date, options); const nextYear = startOfISOWeekYear(addWeeks(thisYear, 60)); const diff = +nextYear - +thisYear; // 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 / millisecondsInWeek); } /* eslint-enable */