Function addDays

pkgs/core/src/addDays/index.ts:53–69

(
  date: DateArg<DateType>,
  amount: number,
  options?: AddDaysOptions<ResultDate> | undefined,
)

 * //=> "2014-09-11"
 */
export function addDays<
  DateType extends Date,
  ResultDate extends Date = DateType,
>(
  date: DateArg<DateType>,
  amount: number,
  options?: AddDaysOptions<ResultDate> | undefined,
): ResultDate {
  const _date = toDate(date, options?.in);
  if (isNaN(amount)) return constructFrom(options?.in || date, NaN);

  // If 0 days, no-op to avoid changing times in the hour before end of DST
  if (!amount) return _date;

  _date.setDate(_date.getDate() + amount);
  return _date;
}