bug#21816: elisp-mode-tests fails on a case-preserving filesystem

[Eli Zaretskii]

> From: Stephen Leake <stephen_leake@stephe-leake.org>
> Cc: Juanma Barranquero <lekktu@gmail.com>,  Eli Zaretskii <eliz@gnu.org>,  
> 21816@debbugs.gnu.org
> Date: Tue, 03 Nov 2015 16:07:00 -0600
> 
> Actually, file-truename works for the cases we've discussed so far:
> 
> (file-truename "c:/Projects/emacs/master/lisp/elide-head.el")
> "c:/Projects/emacs/master/lisp/elide-head.el"
> 
> (file-truename "c:\\Projects\\emacs\\master\\lisp\\elide-head.el")
> "c:/Projects/emacs/master/lisp/elide-head.el"
> 
> (file-truename "c:\\projects\\emacs\\master\\lisp\\elide-head.el")
> "c:/Projects/emacs/master/lisp/elide-head.el"

It seems to work because the part that needs caseless comparison does
exist.  Try using it on a file name where case differences are in a
part that doesn't exist on disk, and you will see the problem.