v11.0.0. yields "Uncaught Error: renderer 'options' does not exist" in code that worked in versions up to v10.0.0

[teehemkay]

Marked version:

11.0.0

Describe the bug

The following code that overrides the link renderer with a version that force opening external links in another window, which worked before v11.0.0. now yield a the following error message Uncaught Error: renderer 'options' does not exist

// from https://github.com/markedjs/marked/issues/655#issuecomment-712380889
const renderer = new marked.Renderer();
const linkRenderer = renderer.link;
renderer.link = (href, title, text) => {
  const html = linkRenderer.call(renderer, href, title, text);
  return href.startsWith('/')
    ? html
    : html.replace(
        /^<a /,
        `<a target="_blank" rel="noreferrer noopener nofollow" `
      );
};

marked.use({ renderer });

To Reproduce
Steps to reproduce the behavior:

Customize marked with the above link renderer

Expected behavior

The the custom link renderer works without yielding an error

[UziTech]

Yes that is because marked.use({ renderer }); is supposed to be an object with the renderer methods not a renderer class. If you change it to the following it should work.

// from https://github.com/markedjs/marked/issues/655#issuecomment-712380889
const markedRenderer = new marked.Renderer();
const linkRenderer = markedRenderer.link;
const renderer = {
  link(href, title, text) {
    const html = linkRenderer.call(this, href, title, text);
    return href.startsWith('/')
      ? html
      : html.replace(
        /^<a /,
        '<a target="_blank" rel="noreferrer noopener nofollow" '
      );
  }
};

marked.use({ renderer });

This is something that was only enforced in typescript until v11. Maybe we should ignore the options property instead of throw an error.

[UziTech]

I created a fix (#3118) to skip the properties instead of throwing an error if the class is used.

[teehemkay]

Thanks a LOT for the explanation and quick fix.
I really appreciate it.