Bug: createElement doesn't support Fragment as root VNode.

Describe the bug

The return type of Fragment is VNode[].

https://github.com/aidenybai/million/blob/7ccc5f021df8ea384d5e03da165633238b52529f/src/jsx.ts#L110

However, createElement doesn’t support passed in an array of VNode:

https://github.com/aidenybai/million/blob/1ea5443220a9d7caf1512862a3b24e968548e638/src/createElement.ts#L10-L13

To Reproduce

import { createElement } from 'million';

function Example() {
  return (
    <>
      {
        ['A', 'B', 'C'].map(i => (<div>{i}</div>))
      }
    </>
  );
}

document.body.appendChild(createElement(Example));

Expected behavior

Render <div>A</div><div>B</div><div>C</div> instead of <undefined></undefined>.

Screenshots

No response

Operating System

Not applicable

Browser

Not applicable

Additional context

No response

[aidenybai]

After some thought and discussion with friends, I think it may be best to leave this out of Million.js’ featureset. I say this because this can fundamentally change some parts of the API – How would createElement deal with a fragment? Just return an array of elements in which the user needs to iterate over and appendChild anyway?

Additionally, the patch system would also need to be reworked, which is feel can make performance (marginally) worse and just less elegant in general. However, this isn’t to say Million will hard discourage the implementation of some sort of Fragment system for the live DOM. For instance, one could create their own mount system if need be.

Plus, no other virtual dom library has support for this directly anyway, so Million.js would be unconventional in standard and poke out of the virtual dom definition if some sort of mounting system was implemented.

Let me know if you think my opinion can be corrected or have any questions.

[aidenybai]

@gustavopch Fragment will (likely) never be supported by the underlying Virtual DOM, but the react compat package will support Fragment