markdown links with one preceding pair of brackets are not rendered correctly

[leonnicolas]

🐛 Bug Report

[][link](#some-title) is rendered to [][link](#some-title)

Links with an even number of preceding bracket pairs are rendered correctly.
Links with an odd number of preceding bracket pairs are not rendered correctly.

Pandoc, github, https://github.com/mity/md4c and docusaurus 1 render these links correctly.

Have you read the Contributing Guidelines on issues?

Yes

To Reproduce

1. clone the docusaurus repo or take any docusaurus 2 project
2. insert [][link](#fast-track) into website/docs/introduction.md
3. Run yarn start
4. Open the browser and navigate to http://localhost:3000/docs/
5. Notice the line with [][link](#fast-track)

Expected behavior

I expected to see
[]link

Actual Behavior

I actually saw
[][link](#fast-track)

Your Environment

• Docusaurus version used: v2.0.0-beta.0 or master

Reproducible Demo

https://codesandbox.io/s/epic-bash-ok5qk?file=/docs/intro.md
and navigate to Tutorial Intro. The broken link is the next line after the title

[nam-hle]

Can you tell me why you need the empty brackets?

[leonnicolas]

Hi @nam-hle,
yes, I came across it when I was auto-generating markdown for a custom resource definition (CRD) in Kubernetes.
Here is an example: https://github.com/prometheus-operator/prometheus-operator/blob/master/Documentation/api.md#alertmanagerlist
Notice the []Altermanager

Generating a website with docusaurus from this markdown would not display the link to Alertmanager correctly.

[slorber]

@leonnicolas I agree that the way it is rendered is surprising.

However, I still don't understand why you want to use double brackets like that. What is your intent?

Is it a bug in your auto-generation system and somehow you expect Docusaurus to handle it better than it currently does?

This is a behavior of MDX, our markdown+React parser, and unfortunately, I don't think we can fix it in the Docusaurus repo.
You can reproduce it here: https://mdxjs.com/playground/ and report it here if it's not already: https://github.com/mdx-js/mdx

And track this issue for when we upgrade MDX (as it might solve the issue):
#4029

[leonnicolas]

However, I still don't understand why you want to use double brackets like that. What is your intent?

Is it a bug in your auto-generation system and somehow you expect Docusaurus to handle it better than it currently does?

It is not a bug in the auto-generation.
[]Altermanager means you can specify a list of Altertmanager.
I think it is a golang thing and the Kubernetes community uses it in their docs a lot.
Apparently, they are not using docusaurus 2 for the generation of their websites.

This is a behavior of MDX, our markdown+React parser, and unfortunately, I don't think we can fix it in the Docusaurus repo.
You can reproduce it here: https://mdxjs.com/playground/ and report it here if it's not already: https://github.com/mdx-js/mdx

Thank you, I was not aware that you were using this parser. When I found https://github.com/facebook/docusaurus/blob/master/packages/docusaurus-utils/src/markdownParser.ts I though you were using dark magic to parse the markdown.

[slorber]

We are converting markdown to JSX in the mdx loader here if that helps: https://github.com/facebook/docusaurus/blob/master/packages/docusaurus-mdx-loader/src/index.js#L67

[slorber]

I understand your use case, however, I'm not. sure how we could easily fix it 😅

Eventually, you could replace such patterns by using HTML entities: [][link](#fast-track)

This shouldn't be too hard to implement a custom remark plugin to pre-process the markdown inputs before mdx

[leonnicolas]

And track this issue for when we upgrade MDX (as it might solve the issue):
#4029

Yes, v2 of MDX will solve the Issue mdx-js/mdx#1559