Mdx: Support comments

[silvenon]

MDX doesn't seem to support comments. I tried both JS and Markdown comments:

const mdx = require('@mdx-js/mdx');

console.log(mdx.sync(`
  import { Foo } from 'bar'

  // this is a JS comment

  # Hello, world!

  <!-- this is a Markdown comment -->

  <Foo />
`));

↓

import { Foo } from 'bar'

export default ({components}) => <MDXTag name="wrapper"  components={components}>
<MDXTag name="p" components={components}>{`// this is a JS comment`}</MDXTag>
<MDXTag name="h1" components={components}>{`Hello, world!`}</MDXTag>
<!-- this is a Markdown comment -->
<Foo /></MDXTag>

[silvenon]

Found them:

# Title

{/* this is a comment */}

Lorem ipsum

This makes sense, so I'll close this.

[silvenon]

No, that also produces a component:

<MDXTag name="p" components={components}>
  {`  {/`}
  <MDXTag name="em" components={components} parentName="p">
    {` this is a comment `}
  </MDXTag>
  {`/}`}
</MDXTag>

[DavidWells]

It looks like this is working for most comments but I just ran into an error with comments in MD

The markdown looks like this:

# login

<!-- AUTO-GENERATED-CONTENT:START (TOC) -->
- [login](#login-1)
<!-- AUTO-GENERATED-CONTENT:END -->

It replaces the top <!-- AUTO-GENERATED-CONTENT:START (TOC) --> correctly but passes over the second comment <!-- AUTO-GENERATED-CONTENT:END --> because there is no newline

This results in a babel error:

Error: Module build failed (from ./node_modules/babel-loader/lib/index.js):
SyntaxError: Unexpected token (15:1)

  13 | <MDXTag name="li" components={components} parentName="ul">
  14 | <MDXTag name="p" components={components} parentName="li"><MDXTag name="a" components={components} parentName="p" props={{"href":"#login-1"}}>{`login`}</MDXTag></MDXTag>
> 15 | <!-- AUTO-GENERATED-CONTENT:END -->
     |  ^
  16 | </MDXTag>
  17 | </MDXTag>
  18 | {/* AUTO-GENERATED-CONTENT:START (GENERATE_COMMANDS_DOCS) */}

I was able to work around it by adding a newline after the list. This markdown works because there is a newline after the list

# login

<!-- AUTO-GENERATED-CONTENT:START (TOC) -->
- [login](#login-1)

<!-- AUTO-GENERATED-CONTENT:END -->

Is there a way to support this without the newline? Thanks!

Loving MDX btw it's freaking sweet

[silvenon]

Thanks for the bug report! Could you please open a new issue? That way it's easier to track it.