react-chrome-redux/lib/strategies/shallowDiff/diff.js

A set of utilities for building Redux applications in Google Chrome Extensions.

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = shallowDiff;

var _constants = require('../constants');

/**
 * Returns a new Object containing only the fields in `new` that differ from `old`
 *
 * @param {Object} old
 * @param {Object} new
 * @return {Array} An array of changes. The changes have a `key`, `value`, and `change`.
 *   The change is either `updated`, which is if the value has changed or been added,
 *   or `removed`.
 */
function shallowDiff(oldObj, newObj) {
  var difference = [];

  Object.keys(newObj).forEach(function (key) {
    if (oldObj[key] !== newObj[key]) {
      difference.push({
        key: key,
        value: newObj[key],
        change: _constants.DIFF_STATUS_UPDATED
      });
    }
  });

  Object.keys(oldObj).forEach(function (key) {
    if (!newObj.hasOwnProperty(key)) {
      difference.push({
        key: key,
        change: _constants.DIFF_STATUS_REMOVED
      });
    }
  });

  return difference;
}