redux - hide getter

hideGetter.js

/* initialState.js */
const books = [ /* ... */ ]
const users = [ /* ... */ ]
const comments = [ /* ... */ ];

const usersSummary = function() {
  return this.users.map(user => ({
    ...user,
    booksCount: user.books.length,
    commentsCount: this.comments.filter(c => c.user === user.id).length
  }));
};

export const initialState = {
  books,
  users,
  comments,
};

Object.defineProperty(initialState, "usersSummary", {
  get: usersSummary,
  enumerable: false
});