bug#67569: 29.1; ruby-mode syntax highlighting breaks with variable named "index" and "/" operator

[Eli Zaretskii <eliz@gnu.org>]

Ping!

> Cc: 67569@debbugs.gnu.org
> Date: Sat, 09 Dec 2023 10:32:22 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> 
> > From: Michael Hoy <mjh@mjhoy.com>
> > Date: Fri, 01 Dec 2023 09:27:47 -0500
> > 
> > In the standard ruby-mode, a variable named "index" followed by a "/"
> > causes the syntax highlighting to break -- it appears that after the
> > slash everything is interpreted as part of a regular expression until
> > another "/" appears.
> > 
> > You can reproduce this fairly easily. using 'emacs -Q', go to the
> > scratch buffer and clear it. Run 'M-x ruby-mode'. Enter something like
> > the following:
> > 
> > def foo
> >   index = 5
> >   x = index / 3
> >   puts "#{x}"
> > end
> > 
> > Note that starting after the "/" until the end, syntax highlighting and
> > indentation break (everything, in my color scheme, is purple). If you
> > add a "/" for instance to the "puts" line, syntax highlighting and
> > indentation will be restored after that.
> > 
> > There is a report here about the bug:
> > https://emacs.stackexchange.com/questions/23802/division-sometimes-breaks-syntax-highlighting-in-ruby-mode
> > The author says in the comments they used "M-x report-emacs-bug", but I
> > couldn't find it (and the comments suggest that it may not have been
> > sent correctly). Apologies if this is already reported!
> 
> Dmitry, any comments?
> 
> 
> 
>