[bug] texlab considers links containing % in \href as a comment

[marcfranquesa]

Links to files containing spaces contain %, and \href allows you to insert the link as is. texlab seems to understand it as a comment and considers the { from \href to not be closed, therefore giving an error expecting a }.

Reproducible example:

\documentclass[12pt]{article}

\usepackage{hyperref}

\begin{document}

\href{https://github.com/latex-lsp/texlab/example%20file.pdf}{URL with \%}.

\end{document}

Thanks!

[nolanking90]

You can escape the % as \%,

\href{https://github.com/latex-lsp/texlab/example\%20file.pdf}{URL with \%}.

Alternatively, you can use a space instead of %20,

\href{https://github.com/latex-lsp/texlab/example file.pdf}{URL with \%}.

Both of these produce the desired result without the diagnostic.

The hyperref documentation says:

The special characters # and % do not need to be escaped in any way (unless
the command is used in the argument of another command).

I read this to mean that hyperref does not care if you escape the % or not.

[marcfranquesa]

Alright, thanks. I assume there is no intention to support having these characters as is (without escaping them) then?

[nolanking90]

I’m open to working on it if you have a suggestion for how to do it. I thought about it for a bit and it’s not obvious to me how to do it without some complicated look ahead while walking the tree. @pfoerster thoughts?

[marcfranquesa]

Great, thanks a lot! I am very new to LSPs, I'll let you know if I come up with something.

[pfoerster]

I’m open to working on it if you have a suggestion for how to do it. I thought about it for a bit and it’s not obvious to me how to do it without some complicated look ahead while walking the tree. @pfoerster thoughts?

I think you need to do this at the parser/lexer level and introduce a PATH token. Walking the tree would be difficult because you have to split and tokenize the COMMENT token again.

[nolanking90]

I think I have this working now, and I've added one unit test for this command:

\href{https://www.test.com/url%20%with%20space}{A test URL}

I could use suggestions for other test cases to check before I push a PR.

[marcfranquesa]

also maybe adding support for \url{}?

and, not sure how much of use it would be, but what about a unit test such as,

% \href{https://www.test.com/url%20%with%20space}{A test URL}