bug#37134: 27.0.50; in LaTeX mode, font-lock / bracket matching on \url behaves incorrectly

bug#37134: 27.0.50; in LaTeX mode, font-lock / bracket matching on \url behaves incorrectly

[Vincent Lefevre]

The "%" character is sometimes use in URL's, thus in \url as a real
character, but the LaTeX mode thinks that's beginning a comment: %
and the following characters in the line are colorized as a comment,
and } isn't seen as a closing bracket. Example:

  \url{http://localhost/#foo%20bar}

/usr/share/texlive/texmf-dist/tex/latex/url/url.sty says:

% A form of \verb that allows linebreaks at certain characters or
% combinations of characters, accepts reconfiguration, and can usually
% be used in the argument to another command.  It is intended for email
% addresses, hypertext links, directories/paths, etc., which normally
% have no spaces.  The font may be selected using the \urlstyle command,
% and new url-like commands can be defined using \urldef.
%
% Usage:    Conditions:
% \url{ }   If the argument contains any "%" or "^^", or ends with
%           "\", it can't be used in the argument to another command.
%           The argument must not contain unbalanced braces.
% \url|  |  ...where "|" is any character not used in the argument and not
%           "{" or a space.  The same restrictions as above except that the
%           argument may contain unbalanced braces.
[...]


In GNU Emacs 27.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.10)
 of 2019-08-20 built on cventin
Repository revision: 50dc4ca8d02a466a7236765edf83ae7cfb02d74c
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12004000
System Description: Debian GNU/Linux bullseye/sid

Recent messages:
Loading /home/vlefevre/share/emacs/site-lisp/mutteditor.el (source)...done
Loading time...done
For information about GNU Emacs and the GNU system, type C-h C-a.

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bug#37134: 27.0.50; in LaTeX mode, font-lock / bracket matching on \url behaves incorrectly

[Lars Ingebrigtsen]

Vincent Lefevre <vincent@vinc17.net> writes:

> The "%" character is sometimes use in URL's, thus in \url as a real
> character, but the LaTeX mode thinks that's beginning a comment: %
> and the following characters in the line are colorized as a comment,
> and } isn't seen as a closing bracket. Example:
>
>   \url{http://localhost/#foo%20bar}

I've now sort of fixed this in Emacs 27 -- the "}" character still has
the wrong face, but the rest has the correct tex-verbatim face.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no