/**
 * The base implementation of methods like `_.findKey` and `_.findLastKey`,
 * without support for iteratee shorthands, which iterates over `collection`
 * using `eachFunc`.
 *
 * @private
 * @param {Array|Object} collection The collection to search.
 * @param {Function} predicate The function invoked per iteration.
 * @param {Function} eachFunc The function to iterate over `collection`.
 * @returns {*} Returns the found element or its key, else `undefined`.
 */
function baseFindKey(collection, predicate, eachFunc) {
  var result;
  eachFunc(collection, function(value, key, collection) {
    if (predicate(value, key, collection)) {
      result = key;
      return false;
    }
  });
  return result;
}

module.exports = baseFindKey;
