Re: Unsafe local variable in eglot.el

[Eli Zaretskii]

> From: João Távora <joaotavora@gmail.com>
> Date: Thu, 9 Mar 2023 09:31:36 +0000
> Cc: emacs-devel@gnu.org
> 
> On Thu, Mar 9, 2023 at 8:00 AM Eli Zaretskii <eliz@gnu.org> wrote:
> >
> > João,
> >
> > This recent change:
> >
> >   commit 0a4b1c0102d4062d24e19340f863b9df25e07ab3
> >   Author:     Joao Távora <joaotavora@gmail.com>
> >   AuthorDate: Wed Mar 1 13:24:07 2023 +0000
> >   Commit:     Joao Távora <joaotavora@gmail.com>
> >   CommitDate: Wed Mar 1 13:27:06 2023 +0000
> >
> >       ; Eglot: improve bug-reference-url-format/bug-reference-url-regexp
> >
> >       * lisp/progmodes/eglot.el (eglot--debbugs-or-github-bug-uri): New 
> > helper.
> >
> > causes trouble when visiting eglot.el.
> 
> I've reproduced it with
> 
>   cd path/to/Emacs
>   src/emacs -Q lisp/progmodes/eglot.el
> 
> But curiously, this doesn't reproduce it
> 
>   src/emacs -Q
>   C-h f eglot RET
>   C-x o TAB RET  ;; to visit the "eglot.el" link
> 
> Why is that?

I don't know.  Maybe the latter already has bug-reference.el loaded?

> Anyway, I just followed the docstring:
> 
>   bug-reference-url-format is a variable defined in `bug-reference.el'.
> 
>   Its value is `eglot--debbugs-or-github-bug-uri'
>   Local in buffer eglot.el; global value is nil
> 
>   Format used to turn a bug number into a URL.
>   The bug number is supplied as a string, so this should have a single %s.
>   This can also be a function designator; it is called without arguments
>    and should return a string.
>   It can use `match-string' to get parts matched against
>   `bug-reference-bug-regexp', specifically:
>    1. issue kind (bug, patch, rfe &c)
>    2. issue number.
> 
>   There is no default setting for this, it must be set per file.
>   If you set it to a symbol in the file Local Variables section,
>   you need to add a `bug-reference-url-format' property to it:
>   (put 'my-bug-reference-url-format 'bug-reference-url-format t)
>   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>   so that it is considered safe, see `enable-local-variables'.

Maybe for the above to work it requires bug-reference.el to be loaded?
Tassilo, any ideas?

> But is a significant number of people using older emacsen to edit
> Emacs's lisp/progmodes/eglot.el?

I do that all the time, since my production sessions always run a
released Emacs.

Moreover, since Eglot is an ELPA package, I'm quite sure people who
use Emacs 28 would do that.