Re: [PATCH] notifications: Don't expand-file-name app-icon.

[Eli Zaretskii <eliz@gnu.org>]

> From: Michael Albinus <michael.albinus@gmx.de>
> Cc: Dmitry Gutov <dmitry@gutov.dev>,  andrew@trop.in,  emacs-devel@gnu.org
> Date: Tue, 25 Jul 2023 21:09:09 +0200
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> If it does not, then the current code is already wrong, isn't it?
> >
> > No, it could be working by sheer luck.
> 
> As always with relative file names: the caller is responsible to use a
> proper default-directory. What else?

Wait a minute.  The icon's file is not processed by Emacs, right?  We
pass it to an external program/library/service, right?

If the file is processed by Emacs itself, then Dmitry is right: the
call to expand-file-name is redundant.  But if the file is processed
by some software outside Emacs, then it is not redundant, because that
external software will handle non-absolute file names as relative to
the cwd of the Emacs process, not to the default-directory of the
buffer that is current when this code runs.

My assumption was that it's the latter: we pass the file name to some
external software.  If that is not the case, then I wonder why
expand-file-name was there to begin with.