HOC as a function won't get generated docs

Similar to #177 but a slightly different scenario...

Given a HOC method like so:

import { bool } from 'prop-types';

const withSomeExtraProps = Wrapped => {
  class HigherOrderComponent extends Component  {
    static propTypes = Object.assign({}, Wrapped.propTypes, {
      /**
       * This should be picked up in the docgenInfo
       */
      anExtraProp: bool,
    });
    static defaultProps = Object.assign({}, Wrapped.defaultProps, {
      anExtraProp: false,
    });
    // ....the rest of the HOC logic
  }
  return HigherOrderComponent;
}

export default withSomeExtraProps;

I understand that this wouldn't automatically mean that the export default withSomeExtraProps(Wrapped) wouldn't automatically get the docgenInfo from the HOC added, but I thought individually this HOC would have it's own docgenInfo that I could reference on it's own.

However, it seems the inner component class here doesn't get recognised and parsed. Does the component class need to be exported for the parser to find it?

Beginne damit, das HOC-Beispiel im Issue zu reproduzieren, und verfolge, wie der Parser die Klasse der inneren Komponente verarbeitet. Bestätige das erwartete docgenInfo-Verhalten und füge eine Testabdeckung hinzu, die zeigt, dass das zusätzliche Prop des HOC erkannt wird; im Bericht werden keine Dateien oder bestehenden Tests genannt.