Docs failing to load due to markdown parser breaking changes

[jakeswenson]

The rustfmt docs site is failing to load for me.

I've tracked it down to what looks like a change in marked.

Specifically the heading function is now handed a single object argument instead of what the current code is expecting.

In marked:

case 'heading': {
  out += this.renderer.heading(token);
  continue;
}

https://github.com/markedjs/marked/blob/70bb55e0af5128a657a14b8b25d7d406661e6936/src/Parser.ts#L69-L71

Marked made an API contract breaking change for this: markedjs/marked#3291

In rustfmt page:

rustfmt/docs/index.html

Lines 172 to 178 in c97996f

	const renderer = new marked.Renderer();
	renderer.heading = function(text, level) {
	const id = htmlToId(text);
	return `<h${level}>
	<a id="${id}" href="#${id}" name="${id}" class="header-link">${text}</a>
	</h${level}>`;
	};

htmlToId is now failing because text is an object, and doesn't have a .trim() method

rustfmt/docs/index.html

Lines 304 to 308 in c97996f

	function htmlToId(text) {
	const tmpl = document.createElement('template');
	tmpl.innerHTML = text.trim();
	return encodeURIComponent(CSS.escape(tmpl.content.textContent));
	}

[jakeswenson]

Quickest fix would be to pin to a proper major version for marked

rustfmt/docs/index.html

Line 8 in c97996f

<script src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>

Setting it to https://cdn.jsdelivr.net/npm/marked@12/marked.min.js works for me locally

[jakeswenson]

Fixed in #6194