old_contents: import { FETCH_LOGIN, RECEIVE_LOGIN, REQUEST_LOGOUT, RECEIVE_LOGOUT } from '../constants/session';
  
  export default (state = {
    isFetching: false,
    isLogin: false
  }, action) => {
    switch(action.type) {
    case FETCH_LOGIN:
      return Object.assign({}, state, {isFetching: true});
    case RECEIVE_LOGIN:
      return Object.assign({}, state, {isFetching: false, isLogin: action.isLogin});
    case REQUEST_LOGOUT:
      return Object.assign({}, state, {isFetching: true});
    case RECEIVE_LOGOUT:
      return Object.assign({}, state, {isFetching: false, isLogin: action.ok});
    default:
      return state;
    }
  };
  
new_contents: import { FETCH_LOGIN_STATUS, RECEIVE_LOGIN_STATUS, FAILED_LOGIN_STATUS, REQUEST_LOGOUT, SUCCESS_LOGOUT, FAILED_LOGOUT } from '../constants/session';
  
  export default (state = {
    isFetching: false,
    isLogin: false
  }, action) => {
    switch(action.type) {
    case FETCH_LOGIN_STATUS:
      return Object.assign({}, state, {isFetching: true});
    case RECEIVE_LOGIN_STATUS:
      return Object.assign({}, state, {isFetching: false, isLogin: action.isLogin});
    case FAILED_LOGIN_STATUS:
      return Object.assign({}, state, {isFetching: false});
    case REQUEST_LOGOUT:
      return Object.assign({}, state, {isFetching: true});
    case SUCCESS_LOGOUT:
      return Object.assign({}, state, {isFetching: false, isLogin: action.ok});
    case FAILED_LOGOUT:
      return Object.assign({}, state, {isFetching: false});
    default:
      return state;
    }
  };
  
subject: Fix constant names