| Leo Repp | 58b9f11 | 2021-11-22 11:57:47 +0100 | [diff] [blame^] | 1 | var baseFindIndex = require('./_baseFindIndex'), |
| 2 | baseIteratee = require('./_baseIteratee'), |
| 3 | toInteger = require('./toInteger'); |
| 4 | |
| 5 | /* Built-in method references for those with the same name as other `lodash` methods. */ |
| 6 | var nativeMax = Math.max; |
| 7 | |
| 8 | /** |
| 9 | * This method is like `_.find` except that it returns the index of the first |
| 10 | * element `predicate` returns truthy for instead of the element itself. |
| 11 | * |
| 12 | * @static |
| 13 | * @memberOf _ |
| 14 | * @since 1.1.0 |
| 15 | * @category Array |
| 16 | * @param {Array} array The array to inspect. |
| 17 | * @param {Function} [predicate=_.identity] The function invoked per iteration. |
| 18 | * @param {number} [fromIndex=0] The index to search from. |
| 19 | * @returns {number} Returns the index of the found element, else `-1`. |
| 20 | * @example |
| 21 | * |
| 22 | * var users = [ |
| 23 | * { 'user': 'barney', 'active': false }, |
| 24 | * { 'user': 'fred', 'active': false }, |
| 25 | * { 'user': 'pebbles', 'active': true } |
| 26 | * ]; |
| 27 | * |
| 28 | * _.findIndex(users, function(o) { return o.user == 'barney'; }); |
| 29 | * // => 0 |
| 30 | * |
| 31 | * // The `_.matches` iteratee shorthand. |
| 32 | * _.findIndex(users, { 'user': 'fred', 'active': false }); |
| 33 | * // => 1 |
| 34 | * |
| 35 | * // The `_.matchesProperty` iteratee shorthand. |
| 36 | * _.findIndex(users, ['active', false]); |
| 37 | * // => 0 |
| 38 | * |
| 39 | * // The `_.property` iteratee shorthand. |
| 40 | * _.findIndex(users, 'active'); |
| 41 | * // => 2 |
| 42 | */ |
| 43 | function findIndex(array, predicate, fromIndex) { |
| 44 | var length = array == null ? 0 : array.length; |
| 45 | if (!length) { |
| 46 | return -1; |
| 47 | } |
| 48 | var index = fromIndex == null ? 0 : toInteger(fromIndex); |
| 49 | if (index < 0) { |
| 50 | index = nativeMax(length + index, 0); |
| 51 | } |
| 52 | return baseFindIndex(array, baseIteratee(predicate, 3), index); |
| 53 | } |
| 54 | |
| 55 | module.exports = findIndex; |