title: Update state with spread operator
body: <p>I want to update state (without hooks):</p>
  <pre><code>class Table extends React.Component {
     
    constructor(props) {
       super(props)
       this.state = {
          players: [
             { number: null, points: null }
             ]
       }
    }
  </code></pre>
  <p>I've tried this code:</p>
  <pre><code>onAddOneClick = () =&gt; {
      this.setState = (state) =&gt; {
       ...state, number: this.state.number,
       ...state, points: state.players.points + 1
      }
  </code></pre>
  <p>but keep getting error:</p>
  <p><a href="https://i.stack.imgur.com/EdAuH.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/EdAuH.png" alt="" /></a></p>