About my previous point, this little function takes care of business when
you want
to toggle the behaviour of display 0 or the absolute line number for the
current line with display-line-numbers set to 'visual or 'relative:

(defun ninrod/toggle-absolute-current-relative-visual-line-number ()
       "Toogle showing absolute line number or 0 for the current line when
display-line-numbers is set to visual or relative"
       (interactive)
       (if display-line-numbers-current-absolute
           (setq display-line-numbers-current-absolute nil)
         (setq display-line-numbers-current-absolute t)))

Boy, is this editor powerful. Holy cow.

Eli, the bug is fixed. All seems fine with the face system now.

On Tue, Jul 4, 2017 at 2:13 PM, Richard Copley <rcopley@gmail.com> wrote:

> On 4 July 2017 at 17:44, Eli Zaretskii <eliz@gnu.org> wrote:
> >> From: Richard Copley <rcopley@gmail.com>
> >> Date: Tue, 4 Jul 2017 17:35:16 +0100
> >> Cc: Eli Zaretskii <eliz@gnu.org>, james@jojojames.com,
> >>       Emacs developers <emacs-devel@gnu.org>
> >>
> >> C-d 0 C-b C-n
> >> C-d 1 C-b C-n
> >> C-d 2 C-p C-p
> >>
> >> This is supposed to change the character at point to 0 and the
> >> characters in the corresponding column in the next two lines to 1
> >> and 2.
> >>
> >> I think that's a common use case and it won't work if
> >> display-line-numbers is on ...
> >
> > Does it really not work for you with display-line-numbers on?
>
> In fact it does work fine, when I test in a new Emacs session
> which isn't affected by the bug I mentioned before.
>
> >> Open xdisp.c and go to line 30, column 30.
> >> Type "C-d C-n C-d C-n C-d C-n C-d C-n"
> >> The first C-n goes to column 30 on line 31 as expected.
> >> The 2nd C-n goes to column 29 on line 31 (expected column 30).
> >> The 3rd C-n goes to column 28 on line 31 (expected 30 (or 29?)).
> >> The 4th C-n goes to column 27 on line 31.
> >
> > I cannot reproduce this, I get column 30 all the time, as expected.
>
> I can't reproduce it either, any more. Sorry about that, the recipe
> seemed stable, but it didn't happen when I tried just now in
> emacs -Q and no longer happens even with my usual customizations.
>
> If I see it again _and_ find a reliable recipe, I'll get back to you.
>
> > Are you running the latest branch?
>
> I was -- it was from just before your latest commit (committer time 18:43).
>
> > If so, what are the values of the
> > related variables?
>
> `display-line-numbers' was `t', `column-number-mode' was turned on
> and every other relevant variable (as far as I know) had its default value.
>