Feature: Async component rendering

[EduApps-CDG]

Async component rendering

Objective 1
This PR aims to support async component rendering through the renderToString function.

Problem:

class RootElem extends Component {
  render() {
    return <>
        <div>Test</div>
        {this.props.children}
    </>
  }
}

class AsyncElem extends Component {
  async render() {
    // do something async...
    return <>
        <div>Async Elem</div>
    </>
  }
}

console.log(
  <RootElem>
    <AsyncElem />
  </RootElem>
);

In the example above, Inferno complains and throw a error because AsyncElem.render() is a Promise<...>. The PR changes renderVNodeToString(vNode, parent, context) to resolve vNode as soon as possible to continue the operation normally.

Objective 2
While changing the test cases, i found a specific test case which is not fullfilled in Security - SSR > renderToString > Should not render invalid tagNames.

Closes Issue
(no issue found)

[EduApps-CDG]

Oh yeah, npm complains while installing dependencies. I had to use npm i --legacy-peer-deps to get it running.

[Havunen]

Hi,

Thanks for the PR, but from where did you get the idea of making render method async? While I think renderToString could be async at the top level changing component render method async sounds like anti-pattern.
A better approach would be to keep the render method synchronous so there is always something to render and then do your async logic in the component lifecycle methods.