react-freezer-js/lib/state.js

Mandatory context-based helpers for freezer-js and react.

'use strict';

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

var _typeof = typeof Symbol === "function" && typeof Symbol.iterator === "symbol" ? function (obj) { return typeof obj; } : function (obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol ? "symbol" : typeof obj; };

exports.isFridge = isFridge;
exports.isObject = isObject;
exports.morph = morph;

var _freezerJs = require('freezer-js');

var _freezerJs2 = _interopRequireDefault(_freezerJs);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function isFridge(fridge) {
  return fridge instanceof _freezerJs2.default;
}

function isObject(value) {
  // http://jsperf.com/isobject4
  return value !== null && (typeof value === 'undefined' ? 'undefined' : _typeof(value)) === 'object';
}

// Applies a function to the current state to generate a delta and commits
// the delta (i.e. modifies the state) if it is not `undefined`.
// It handles promises as well.
function morph(fridge, fn) {
  // inject the state and the commit function
  fn.call(fridge, {
    state: fridge.get(),
    commit: function commit(delta) {
      return _commit(fridge, delta);
    }
  });
}

// Apply the delta to the state (side-effect) and returns the delta,
// so that it can easily be tapped into a promise chain.
// check freezer-js documentation for more about update:
// @see https://github.com/arqex/freezer#update-methods
function _commit(fridge, delta) {
  if (!isFridge(fridge)) {
    throw new Error('commit() was applied on a non-freezer instance');
  }
  if (!isObject(delta)) {
    throw new Error('delta should be an object');
  }
  fridge.get().set(delta);
  return delta;
}
exports.commit = _commit;