Function copyObject

test/babel.js:2805–2827

* Copies properties of `source` to `object`. * * @private * @param {Object} source The object to copy properties from. * @param {Array} props The property identifiers to copy. * @param {Object} [object={}] The object to copy properties to. * @param {Function} [customizer] The function to

(source, props, object, customizer)

	 * @returns {Object} Returns `object`.
	 */
	function copyObject(source, props, object, customizer) {
	  var isNew = !object;
	  object || (object = {});

	  var index = -1,
	      length = props.length;

	  while (++index < length) {
	    var key = props[index];

	    var newValue = customizer ? customizer(object[key], source[key], key, object, source) : undefined;

	    if (newValue === undefined) {
	      newValue = source[key];
	    }
	    if (isNew) {
	      baseAssignValue(object, key, newValue);
	    } else {
	      assignValue(object, key, newValue);
	    }
	  }
	  return object;
	}

	module.exports = copyObject;