HORIZON PROJECT

var copyObject = require('./_copyObject'),

    createAssigner = require('./_createAssigner'),

    keysIn = require('./keysIn');

/**

 * This method is like `_.assignIn` except that it accepts `customizer`

 * which is invoked to produce the assigned values. If `customizer` returns

 * `undefined`, assignment is handled by the method instead. The `customizer`

 * is invoked with five arguments: (objValue, srcValue, key, object, source).

 *

 * **Note:** This method mutates `object`.

 *

 * @static

 * @memberOf _

 * @since 4.0.0

 * @alias extendWith

 * @category Object

 * @param {Object} object The destination object.

 * @param {...Object} sources The source objects.

 * @param {Function} [customizer] The function to customize assigned values.

 * @returns {Object} Returns `object`.

 * @see _.assignWith

 * @example

 *

 * function customizer(objValue, srcValue) {

 *   return _.isUndefined(objValue) ? srcValue : objValue;

 * }

 *

 * var defaults = _.partialRight(_.assignInWith, customizer);

 *

 * defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });

 * // => { 'a': 1, 'b': 2 }

 */

var assignInWith = createAssigner(function(object, source, srcIndex, customizer) {

  copyObject(source, keysIn(source), object, customizer);

});

module.exports = assignInWith;