higher-order-reducers/lib/merge-states.js

A library of simple everyday reducer utility functions

'use strict';

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

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

var _isPlainObject = require('is-plain-object');

var _isPlainObject2 = _interopRequireDefault(_isPlainObject);

var _objectAssign = require('object-assign');

var _objectAssign2 = _interopRequireDefault(_objectAssign);

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

var mergeStates = function mergeStates(reducer) {
  if (typeof reducer !== 'function') {
    throw new Error('Argument supplied to "mergeStates" is not a reducer');
  }

  return function (state, action) {
    if (!(0, _isPlainObject2.default)(state)) {
      var type = typeof state === 'undefined' ? 'undefined' : _typeof(state);
      throw new Error('"mergeStates" only works with plain object states, but got a "' + type + '"');
    }
    var nextState = reducer(state, action);
    if (!(0, _isPlainObject2.default)(nextState)) {
      var _type = typeof nextState === 'undefined' ? 'undefined' : _typeof(nextState);
      throw new Error('The reducer in "mergeStates" did not return a plain object. Instead it was a "' + _type + '"');
    }
    return (0, _objectAssign2.default)({}, state, nextState);
  };
};

exports.default = mergeStates;