Function getWeek

pkgs/core/src/getWeek/index.ts:57–68

(
  date: DateArg<Date> & {},
  options?: GetWeekOptions | undefined,
)

 * //=> 53
 */
export function getWeek(
  date: DateArg<Date> & {},
  options?: GetWeekOptions | undefined,
): number {
  const _date = toDate(date, options?.in);
  const diff = +startOfWeek(_date, options) - +startOfWeekYear(_date, options);

  // 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) + 1;
}