title: Not Return New State React Redux
body: <p>I trying to make this function to add a new state at Redux.</p>
  <pre><code>  const initialFriend = {
      current: [],
      possible: ['a', 'b', 'c'],
    };
  
    const friendReducer = (state = initialFriend, action) =&gt; {
    switch (action.type) {
      case ADD_FRIEND:
        const { current, possible } = state;
  
        const newArrayPossible = possible.slice();
        const newArrayCurrent = current.slice();
  
        const addedFriend = newArrayPossible.splice(action.payload, 1);
  
        newArrayCurrent.push(addedFriend);
  
        const newState = { newArrayCurrent, newArrayPossible };
  
        return newState;
      default:
        return state;
    }
  };
  </code></pre>
  <p>But the problem is I can't get the new state when I trigger ADD_FRIEND actions. Anyone can help me?</p>