bug#44420: 28.0.50; vc-register, under vc-dir buffer, says file already registered

[Dmitry Gutov]

On 05.11.2020 12:32, Pankaj Jangid wrote:
> > > > Including file name in the "File already registered" message may help to
> > > > understand whats going on though.
> > > This could be a long list. We can just say "Marked file(s) already
> > > registered".
> > Files in the list are checked one by one and error is returned for the
> > first registered file.  IMO filename will fit well in the error message.
> Yes one filename will definitely fit.

Does this work for y'all?

diff --git a/lisp/vc/vc.el b/lisp/vc/vc.el
index 8def7da377..32664bcd25 100644
--- a/lisp/vc/vc.el
+++ b/lisp/vc/vc.el
@@ -1391,7 +1391,7 @@ vc-register
        (unless fname
          (setq fname buffer-file-name))
        (when (vc-call-backend backend 'registered fname)
-         (error "This file is already registered"))
+         (error "This file is already registered: %s" fname))
        ;; Watch out for new buffers of size 0: the corresponding file
        ;; does not exist yet, even though buffer-modified-p is nil.
        (when bname