lodash/object/findLastKey.js

define(['../internal/baseCallback', '../internal/baseFind', '../internal/baseForOwnRight'], function(baseCallback, baseFind, baseForOwnRight) {

  /**
   * This method is like `_.findKey` except that it iterates over elements of
   * a collection in the opposite order.
   *
   * If a property name is provided for `predicate` the created `_.property`
   * style callback returns the property value of the given element.
   *
   * If a value is also provided for `thisArg` the created `_.matchesProperty`
   * style callback returns `true` for elements that have a matching property
   * value, else `false`.
   *
   * If an object is provided for `predicate` the created `_.matches` style
   * callback returns `true` for elements that have the properties of the given
   * object, else `false`.
   *
   * @static
   * @memberOf _
   * @category Object
   * @param {Object} object The object to search.
   * @param {Function|Object|string} [predicate=_.identity] The function invoked
   *  per iteration.
   * @param {*} [thisArg] The `this` binding of `predicate`.
   * @returns {string|undefined} Returns the key of the matched element, else `undefined`.
   * @example
   *
   * var users = {
   *   'barney':  { 'age': 36, 'active': true },
   *   'fred':    { 'age': 40, 'active': false },
   *   'pebbles': { 'age': 1,  'active': true }
   * };
   *
   * _.findLastKey(users, function(chr) { return chr.age < 40; });
   * // => returns `pebbles` assuming `_.findKey` returns `barney`
   *
   * // using the `_.matches` callback shorthand
   * _.findLastKey(users, { 'age': 36, 'active': true });
   * // => 'barney'
   *
   * // using the `_.matchesProperty` callback shorthand
   * _.findLastKey(users, 'active', false);
   * // => 'fred'
   *
   * // using the `_.property` callback shorthand
   * _.findLastKey(users, 'active');
   * // => 'pebbles'
   */
  function findLastKey(object, predicate, thisArg) {
    predicate = baseCallback(predicate, thisArg, 3);
    return baseFind(object, predicate, baseForOwnRight, true);
  }

  return findLastKey;
});