bug#32177: Current line number shifts one column to the left.

[Eli Zaretskii <eliz@gnu.org>]

> Date: Mon, 16 Jul 2018 10:36:12 -0700
> From: Keith David Bershatsky <esq@lawlist.com>
> 
> 1.  Launch a newly built GUI version of Emacs master branch (07/16/2018).
> 
> 2.  WINDOWS XP -- GUI Emacs:  From the *GNU Emacs* welcome screen, type M-: and evaluate the following:
> 
>     (progn
>       (switch-to-buffer (get-buffer-create "foo"))
>       (setq header-line-format "foo")
>       (display-line-numbers-mode 1)
>       (setq bidi-display-reordering nil)
>       (dotimes (i 57)
>         (insert "\n"))
>       (recenter 1)
>       (sit-for 1)
>       (insert "@"))
> 
> [OR]
> 
> 2.  OSX 10.6.8 GUI Emacs:  From the *GNU Emacs* welcome screen, type M-: and evaluate the following:
> 
>     (progn
>       (switch-to-buffer (get-buffer-create "foo"))
>       (setq header-line-format "foo")
>       (display-line-numbers-mode 1)
>       (setq bidi-display-reordering nil)
>       (dotimes (i 50)
>         (insert "\n"))
>       (recenter 1)
>       (sit-for 1)
>       (insert "@"))
> 
> 3.  Observe that line number 58 (on Windows XP), or line number 51 (on OSX 10.6.8), shifts one column to the left of where it should be.  Here is a link to a screenshot depicting the bug with both versions of Emacs (Windows / OSX):
> 
> https://www.lawlist.com/images/bug_07_16_2018.png

Actually, the screenshot shows that line number 57 is to the right of
where it should have been.

In any case, I cannot reproduce this here, not in "emacs -Q", not on
master and not on the emacs-26 branch.

Why did you need to turn off bidi-display-reordering?  Does the
problem go away when you don't do that?