Markdown syntax highlighting should ignore math inside $$

[slochower]

• VSCode Version: 1.12.2
• OS Version: macOS Sierra 10.12.5

Steps to Reproduce:

1. Create a markdown document and use inline LaTeX (e.g. $a_{b}$) for math.
2. VSCode interprets the markdown underscore to mean italic text -- instead of math subscript -- and will make the markdown text italic until it sees a matching underscore delimiter.

I think this is behavior is theme dependent, but I'm not sure. Changing themes just changes how the text between the underscores is rendered (italic or colored or whatever). I believe that markdown delimiters (_ and *) in math mode should be ignored the way they are in code blocks.

[mjbvz]

The builtin markdown extension targets commonmark which does not support that syntax.

An extension may be able to extend the builtin markdown grammar using an injection similar to https://github.com/mjbvz/vscode-fenced-code-block-grammar-injection-example or the extension could provide its own markdown grammar that includes math support in its grammar

[slochower]

I'm not sure I see how the injection can be used in the example you linked. (It looks like it calls source.js to change what happens inside superjs code blocks, AFAICT, but I don't see an example of source.js.) In lieu of an extension, is there a way to turn off syntax highlighting _ in the theme? That may be simpler for now.

[mjbvz]

Instead of injecting to the fenced code block rules like in the linked example, you would want to add an injection for the latex grammar to #paragraph in this case.

The syntax highlighting is up to the grammar. You can customize the grammar if you want to handle _ specially for markdown

[slochower]

I think I can figure out how to do this with a couple more clues. If I use your codeblock.json as a template, I assume I'll have to change the injectionSelector to something for inline LaTeX. Where are the list of these grammars (i.e., where did you get markup.fenced_code.block.markdown)? Also, I'm still not clear what happens with "include": "source.js". Is this the file that controls syntax highlighting for the injected grammar inside the begin and end patterns? Would I have to pull this from an extension for LaTeX?