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

[Eli Zaretskii]

> From: Juanma Barranquero <lekktu@gmail.com>
> Date: Tue, 3 Nov 2015 17:42:28 +0100
> Cc: Dmitry Gutov <dgutov@yandex.ru>, 21816@debbugs.gnu.org, 
>       Stephen Leake <stephen_leake@stephe-leake.org>
> 
> > This isn't a xref-specific problem, so I think it should have a more
> > general solution that any package could use. It's not reasonable to
> > expect from every Emacs developer to be an expert on subtle aspects of
> > comparing Windows file names. We should provide a tested solution for
> > that.
> 
> That would be helpful in general, but wouldn't help with the case that now, to
> compare two xref-location instances, you have to delve into their innards.
> Different problems.
> 
> <rambling>Unless you're proposing a variant of `equal' with better
> file-comparing abilities... which doesn't make sense because 
> `equal-super-duper
> ` wouldn't have a way to know that some things are filenames and not just
> arbitrary strings that match a filename just by happenstance...</rambling>

You mean, ref doesn't know that some strings are file names and some
aren't?  Then how does it know they are strings and not symbols or
something else?  This is Lisp, not C.