Testing Immutable.js as data store that will always point to the most updated reference of the map

test.js

//with store
const STORE = {
  head: new Map(),
  undo: () => {
    const action = STORE.queue.pop();
    STORE.head = STORE.queue[STORE.queue.length - 1];
    return action;
  },
  queue: []
};
STORE.queue.push(STORE.head);
['get'].forEach(k => STORE[k] = (...args) => STORE.head[k](...args));
['set', 'merge'].forEach(k => STORE[k] = (...args) => {
  STORE.head = STORE.head[k](...args);
  STORE.queue.push(STORE.head);
});
STORE.merge({
  0: 'zero'
});
STORE.set(1, 'one');
console.log(STORE.get('0')); //key was changed to string via Map.merge (not my doing)
console.log(STORE.get(1));
console.log(STORE.queue[0].get(1)); //should NOT work (empty map, first head reference)
const oldStore = STORE.undo();
console.log(STORE.get(1)); //should NOT work
STORE.undo();
console.log(STORE.get('0')); //should NOT work
//oldStore before undo (SHOULD WORK)
console.log(oldStore.get('0'));
console.log(oldStore.get(1));

console.log('USING MAP AS IS');
//without store
const test = new Map();
test.merge({
  0: 'zero'
});
test.set(1, 'one');
console.log(test.get('0')); //should NOT work
console.log(test.get(1)); //should NOT work