define(['./_copyObject', './keysIn'], function(copyObject, keysIn) {

  /**
   * The base implementation of `_.assignIn` without support for multiple sources
   * or `customizer` functions.
   *
   * @private
   * @param {Object} object The destination object.
   * @param {Object} source The source object.
   * @returns {Object} Returns `object`.
   */
  function baseAssignIn(object, source) {
    return object && copyObject(source, keysIn(source), object);
  }

  return baseAssignIn;
});