state func setter form should use Readonly wrapper?

[cynecx]

import { render } from 'solid-js/web';
import { createState } from 'solid-js';

function Counter() {
  const [state, setState] = createState({num: 0});
  const increment = () => setState(x => { return {...x, num: x.num + 1} });
  // This doesn't work obviously:
  // const increment = () => setState(x => { x.num += 1; return x; })

  return (
    <button type="button" onClick={increment}>
      {state.num}
    </button>
  );
}

render(() => <Counter />, document.getElementById('app'))

Mutating x (the state) inside a setState "setter func" is almost always wrong (most of the times). Can we restrict this by using Typescript's Readonly<T> wrapper?

[ryansolid]

Yeah that seems reasonable. If you change it like that when it goes to diff it doesn't see a diff and it never notifies. I'm open to a PR, or I will get around to it when I'm able.