diff options
Diffstat (limited to 'date-fns/src/min/index.ts')
-rw-r--r-- | date-fns/src/min/index.ts | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/date-fns/src/min/index.ts b/date-fns/src/min/index.ts new file mode 100644 index 0000000..b29763d --- /dev/null +++ b/date-fns/src/min/index.ts @@ -0,0 +1,73 @@ +import toDate from '../toDate/index' +import requiredArgs from '../_lib/requiredArgs/index' + +/** + * @name min + * @category Common Helpers + * @summary Returns the earliest of the given dates. + * + * @description + * Returns the earliest of the given dates. + * + * ### v2.0.0 breaking changes: + * + * - [Changes that are common for the whole library](https://github.com/date-fns/date-fns/blob/master/docs/upgradeGuide.md#Common-Changes). + * + * - `min` function now accepts an array of dates rather than spread arguments. + * + * ```javascript + * // Before v2.0.0 + * const date1 = new Date(1989, 6, 10) + * const date2 = new Date(1987, 1, 11) + * const minDate = min(date1, date2) + * + * // v2.0.0 onward: + * const dates = [new Date(1989, 6, 10), new Date(1987, 1, 11)] + * const minDate = min(dates) + * ``` + * + * @param {Date[]|Number[]} datesArray - the dates to compare + * @returns {Date} - the earliest of the dates + * @throws {TypeError} 1 argument required + * + * @example + * // Which of these dates is the earliest? + * const result = min([ + * new Date(1989, 6, 10), + * new Date(1987, 1, 11), + * new Date(1995, 6, 2), + * new Date(1990, 0, 1) + * ]) + * //=> Wed Feb 11 1987 00:00:00 + */ +export default function min(dirtyDatesArray: Date[] | number[]): Date { + requiredArgs(1, arguments) + + let datesArray: Date[] | number[] + // `dirtyDatesArray` is Array, Set or Map, or object with custom `forEach` method + if (dirtyDatesArray && typeof dirtyDatesArray.forEach === 'function') { + datesArray = dirtyDatesArray + // If `dirtyDatesArray` is Array-like Object, convert to Array. + } else if (typeof dirtyDatesArray === 'object' && dirtyDatesArray !== null) { + datesArray = Array.prototype.slice.call(dirtyDatesArray) + } else { + // `dirtyDatesArray` is non-iterable, return Invalid Date + return new Date(NaN) + } + + let result: Date | undefined + + datesArray.forEach(function (dirtyDate: Date | number) { + let currentDate = toDate(dirtyDate) + + if ( + result === undefined || + result > currentDate || + isNaN(currentDate.getDate()) + ) { + result = currentDate + } + }) + + return result || new Date(NaN) +} |