text: import _ from 'lodash';
  import { FETCH_POSTS, FETCH_POST, DELETE_POST } from '../actions';
  
  export default function(state = {}, action) {
  
    switch(action.type) {
    case FETCH_POSTS: 
      return _.mapKeys(action.payload.data, 'id');
    case FETCH_POST:
      return { ...state, [action.payload.data.id]: action.payload.data };
      /* es5
      const post = action.payload.data;
      const newState = { ...state };
      newState[post.id] = post;
      return newState;
      */
  
    case DELETE_POST:
      return _.omit(state, action.payload);
      
    default: 
      return state;
    }
  }