import { getRoundingMethod } from "./_lib/getRoundingMethod.mjs"; import { constructFrom } from "./constructFrom.mjs"; import { toDate } from "./toDate.mjs"; /** * The {@link roundToNearestHours} function options. */ /** * @name roundToNearestHours * @category Hour Helpers * @summary Rounds the given date to the nearest hour * * @description * Rounds the given date to the nearest hour (or number of hours). * Rounds up when the given date is exactly between the nearest round hours. * * @typeParam DateType - The `Date` type, the function operates on. Gets inferred from passed arguments. Allows to use extensions like [`UTCDate`](https://github.com/date-fns/utc). * * @param date - The date to round * @param options - An object with options. * * @returns The new date rounded to the closest hour * * @example * // Round 10 July 2014 12:34:56 to nearest hour: * const result = roundToNearestHours(new Date(2014, 6, 10, 12, 34, 56)) * //=> Thu Jul 10 2014 13:00:00 * * @example * // Round 10 July 2014 12:34:56 to nearest half hour: * const result = roundToNearestHours(new Date(2014, 6, 10, 12, 34, 56), { nearestTo: 6 }) * //=> Thu Jul 10 2014 12:00:00 * @example * // Round 10 July 2014 12:34:56 to nearest half hour: * const result = roundToNearestHours(new Date(2014, 6, 10, 12, 34, 56), { nearestTo: 8 }) * //=> Thu Jul 10 2014 16:00:00 * @example * // Floor (rounds down) 10 July 2014 12:34:56 to nearest hour: * const result = roundToNearestHours(new Date(2014, 6, 10, 1, 23, 45), { roundingMethod: 'ceil' }) * //=> Thu Jul 10 2014 02:00:00 * * @example * // Ceil (rounds up) 10 July 2014 12:34:56 to nearest quarter hour: * const result = roundToNearestHours(new Date(2014, 6, 10, 12, 34, 56), { roundingMethod: 'floor', nearestTo: 8 }) * //=> Thu Jul 10 2014 08:00:00 */ export function roundToNearestHours(date, options) { const nearestTo = options?.nearestTo ?? 1; if (nearestTo < 1 || nearestTo > 12) return constructFrom(date, NaN); const _date = toDate(date); const fractionalMinutes = _date.getMinutes() / 60; const fractionalSeconds = _date.getSeconds() / 60 / 60; const fractionalMilliseconds = _date.getMilliseconds() / 1000 / 60 / 60; const hours = _date.getHours() + fractionalMinutes + fractionalSeconds + fractionalMilliseconds; // Unlike the `differenceIn*` functions, the default rounding behavior is `round` and not 'trunc' const method = options?.roundingMethod ?? "round"; const roundingMethod = getRoundingMethod(method); // nearestTo option does not care daylight savings time const roundedHours = roundingMethod(hours / nearestTo) * nearestTo; const result = constructFrom(date, _date); result.setHours(roundedHours, 0, 0, 0); return result; } // Fallback for modularized imports: export default roundToNearestHours;