import { toDate } from "./toDate.mjs"; /** * @name compareDesc * @category Common Helpers * @summary Compare the two dates reverse chronologically and return -1, 0 or 1. * * @description * Compare the two dates and return -1 if the first date is after the second, * 1 if the first date is before the second or 0 if dates are equal. * * @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 dateLeft - The first date to compare * @param dateRight - The second date to compare * * @returns The result of the comparison * * @example * // Compare 11 February 1987 and 10 July 1989 reverse chronologically: * const result = compareDesc(new Date(1987, 1, 11), new Date(1989, 6, 10)) * //=> 1 * * @example * // Sort the array of dates in reverse chronological order: * const result = [ * new Date(1995, 6, 2), * new Date(1987, 1, 11), * new Date(1989, 6, 10) * ].sort(compareDesc) * //=> [ * // Sun Jul 02 1995 00:00:00, * // Mon Jul 10 1989 00:00:00, * // Wed Feb 11 1987 00:00:00 * // ] */ export function compareDesc(dateLeft, dateRight) { const _dateLeft = toDate(dateLeft); const _dateRight = toDate(dateRight); const diff = _dateLeft.getTime() - _dateRight.getTime(); if (diff > 0) { return -1; } else if (diff < 0) { return 1; // Return 0 if diff is 0; return NaN if diff is NaN } else { return diff; } } // Fallback for modularized imports: export default compareDesc;