timepiece/node_modules/date-fns/closestIndexTo.mjs

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2024-05-14 14:54:12 +00:00
import { toDate } from "./toDate.mjs";
/**
* @name closestIndexTo
* @category Common Helpers
* @summary Return an index of the closest date from the array comparing to the given date.
*
* @description
* Return an index of the closest date from the array comparing to the given date.
*
* @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 dateToCompare - The date to compare with
* @param dates - The array to search
*
* @returns An index of the date closest to the given date or undefined if no valid value is given
*
* @example
* // Which date is closer to 6 September 2015?
* const dateToCompare = new Date(2015, 8, 6)
* const datesArray = [
* new Date(2015, 0, 1),
* new Date(2016, 0, 1),
* new Date(2017, 0, 1)
* ]
* const result = closestIndexTo(dateToCompare, datesArray)
* //=> 1
*/
export function closestIndexTo(dateToCompare, dates) {
const date = toDate(dateToCompare);
if (isNaN(Number(date))) return NaN;
const timeToCompare = date.getTime();
let result;
let minDistance;
dates.forEach(function (dirtyDate, index) {
const currentDate = toDate(dirtyDate);
if (isNaN(Number(currentDate))) {
result = NaN;
minDistance = NaN;
return;
}
const distance = Math.abs(timeToCompare - currentDate.getTime());
if (result == null || distance < minDistance) {
result = index;
minDistance = distance;
}
});
return result;
}
// Fallback for modularized imports:
export default closestIndexTo;