Files
lodash/findLastIndex.js
2017-01-10 01:46:24 -08:00

45 lines
1.3 KiB
JavaScript

import baseFindIndex from './.internal/baseFindIndex.js';
import toInteger from './toInteger.js';
/* Built-in method references for those with the same name as other `lodash` methods. */
const nativeMax = Math.max;
const nativeMin = Math.min;
/**
* This method is like `findIndex` except that it iterates over elements
* of `collection` from right to left.
*
* @since 2.0.0
* @category Array
* @param {Array} array The array to inspect.
* @param {Function} predicate The function invoked per iteration.
* @param {number} [fromIndex=array.length-1] The index to search from.
* @returns {number} Returns the index of the found element, else `-1`.
* @example
*
* const users = [
* { 'user': 'barney', 'active': true },
* { 'user': 'fred', 'active': false },
* { 'user': 'pebbles', 'active': false }
* ];
*
* findLastIndex(users, o => o.user == 'pebbles');
* // => 2
*/
function findLastIndex(array, predicate, fromIndex) {
const length = array == null ? 0 : array.length;
if (!length) {
return -1;
}
let index = length - 1;
if (fromIndex !== undefined) {
index = toInteger(fromIndex);
index = fromIndex < 0
? nativeMax(length + index, 0)
: nativeMin(index, length - 1);
}
return baseFindIndex(array, predicate, index, true);
}
export default findLastIndex;