icssDService/node_modules.bak/jstransform/visitors/es6-object-computed-property-visitors.js

/**
 * Copyright 2013-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 */

/*jslint node: true*/

var es6ObjectConciseMethods = require('./es6-object-concise-method-visitors');
var es7SpreadProperties = require('./es7-spread-property-visitors');

var Syntax = require('esprima-fb').Syntax;
var utils = require('../src/utils');

function process(traverse, node, path, state) {
  utils.catchupWhiteSpace(node.range[0], state);
  traverse(node, path, state);
  utils.catchup(node.range[1], state);
}

/**
 * Note: This visitor is capable of handling the following transforms too:
 * - ES7 object literal spread,
 * - ES6 object concise methods,
 * - ES6 object short notation,
 * This is because of limitations in the jstransform framework, which isn't
 * capable of feeding the output of one visitor to another. Additionally,
 * any attempt to share logic between these visitors only increases code
 * complixity. And so, we are forced to create a single complex one that
 * handles all cases.
 *
 * {alpha: 12, \'beta\': 34, ['gam' + 'ma']: 56} // before
 * (_={},_.alpha=12,_['beta']=34,_['gam' + 'ma']=56,_) // after
 */
function es6ObjectComputedProperties(traverse, node, path, state) {
  var obj = utils.injectTempVar(state);
  utils.append('(' + obj + '={}', state);
  for (var ii = 0; ii < node.properties.length; ++ii) {
    var property = node.properties[ii];
    utils.append(',', state);

    if (property.type === Syntax.SpreadProperty) {
      utils.append('Object.assign(' + obj, state);
      var nextComputedPropertyIndex = ii + 1;
      while (
        nextComputedPropertyIndex < node.properties.length &&
        !node.properties[nextComputedPropertyIndex].computed
      ) {
        nextComputedPropertyIndex += 1;
      }
      utils.catchupWhiteSpace(node.properties[ii].range[0], state);
      var lastWasSpread = es7SpreadProperties.renderSpreadProperties(
        traverse,
        node.properties.slice(ii, nextComputedPropertyIndex),
        path,
        state,
        true // previousWasSpread
      );
      utils.append((lastWasSpread ? '' : '}') + ')', state);
      ii = nextComputedPropertyIndex - 1;
      continue;

    // short notation / dot access
    } else if (
      property.type === Syntax.Property &&
      property.key.type === Syntax.Identifier &&
      !property.computed
    ) {
      utils.append(obj + '.' + property.key.name + '=', state);

    // literals / computed properties
    } else if (property.type === Syntax.Property) {
      utils.append(obj + '[', state);
      process(traverse, property.key, path, state);
      utils.append(']=', state);
    }

    // concise methods
    if (property.method === true) {
      utils.catchupWhiteSpace(property.key.range[1], state);
      es6ObjectConciseMethods.renderConciseMethod(traverse, property, path, state);
    }
    process(traverse, property.value, path, state);
  }
  utils.catchupWhiteSpace(node.range[1], state);
  utils.append(',' + obj + ')', state);
  return false;
}
es6ObjectComputedProperties.test = function(node, path, state) {
  if (node.type !== Syntax.ObjectExpression) {
    return false;
  }
  for (var ii = 0; ii < node.properties.length; ++ii) {
    if (node.properties[ii].computed) {
      return true;
    }
  }
  return false;
};

exports.visitorList = [
  es6ObjectComputedProperties,
];