Abstract creating an action that has a type and a payload

createAction.js

// Abstract creating an action that has a type and a payload:
// const addTodo = createAction(ADD_TODO);
// is equivalent to
// const addTodo = (payload) => ({ type: ADD_TODO, payload });
//
// Optionally you can pass in a payloadMap when defining an action
// to reshape the payload before storing it on the action.

import { identity } from 'lodash';

export default function createAction(type, payloadMap) {
  const payloadCreator = typeof payloadMap === 'function' ? payloadMap : identity;
  return (...args) => ({ type, payload: payloadCreator(...args) });
}