user-selectors.js

import { createSelector } from 'reselect'

export const getIsAuthenticated = state => state.isAuthenticated
export const getIsEligibleForPromo = state => state.isEligibleForPromo

const getBasket = state => state.basket
const getLatestOrderItems = state => state.orders.latest.items

export const getBasketContents = createSelector(
  [getBasket, getLatestOrderItems],
  (basket, latestOrderItems) => basket.map(item => !lastestOrderItems.includes(item.id))
)