/**
   * @fileoverview Patch for estraverse
   * @author Toru Nagashima
   * @copyright 2015 Toru Nagashima. All rights reserved.
   * See LICENSE file in root directory for full license.
   */
  "use strict";
  
  //------------------------------------------------------------------------------
  // Requirements
  //------------------------------------------------------------------------------
  
  var estraverse = require("estraverse"),
      jsxKeys = require("estraverse-fb/keys");
  
  //------------------------------------------------------------------------------
  // Helers
  //------------------------------------------------------------------------------
  
  var experimentalKeys = {
      ExperimentalRestProperty: ["argument"],
      ExperimentalSpreadProperty: ["argument"]
  };
  
  /**
   * Adds a given keys to Syntax and VisitorKeys of estraverse.
   *
   * @param {object} keys - Key definitions to add.
   *   This is an object as map.
   *   Keys are the node type.
   *   Values are an array of property names to visit.
   * @returns {void}
   */
  function installKeys(keys) {
      for (var key in keys) {
          if (keys.hasOwnProperty(key)) {
              estraverse.Syntax[key] = key;
              if (keys[key]) {
                  estraverse.VisitorKeys[key] = keys[key];
              }
          }
      }
  }
  
  // Add JSX node types.
  installKeys(jsxKeys);
  // Add Experimental node types.
  installKeys(experimentalKeys);
  
  //------------------------------------------------------------------------------
  // Public Interface
  //------------------------------------------------------------------------------
  
  module.exports = estraverse;