bug#61580: line-prefix and display text properties cause odd cursor movement

[Eli Zaretskii]

> Cc: 61580@debbugs.gnu.org
> Date: Sat, 18 Feb 2023 13:42:31 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> 
> > From: Darius Foo <darius.foo.tw@gmail.com>
> > Date: Sat, 18 Feb 2023 00:39:00 +0800
> > 
> > When moving the cursor up and down on lines which have both line-prefix and 
> > display text properties, the
> > cursor column isn't preserved, jumping ahead or back by a fixed amount.
> > 
> > This can be reproduced with the following config
> > 
> >       (add-text-properties 12 13 '(line-prefix "  "))
> >       (add-text-properties 27 28 '(line-prefix "  "))
> >       (add-text-properties 57 58 '(line-prefix "    "))
> >       (add-text-properties 72 73 '(line-prefix "    "))
> > 
> >       (add-text-properties 12 13 '(display "•"))
> >       (add-text-properties 27 28 '(display "•"))
> >       (add-text-properties 57 58 '(display "•"))
> >       (add-text-properties 72 73 '(display "•"))
> > 
> > and this input file (which mimics org-indent).
> > 
> >     * h1
> >     ** h2
> >     - a.y.........
> >     - x...........
> >     *** h3
> >     **** h4
> >     - ....w.......
> >     - z...........
> > 
> > With the cursor on x, pressing up moves it to y instead of a, and pressing 
> > down moves it back to x. The
> > amount moved depends on the indentation added by line-prefix: with the 
> > cursor on z, pressing up moves it to
> > w.
> 
> Thanks, should be fixed now on the emacs-29 branch.
> 
> (This bug was a leftover from incomplete fix of bug#49695.)

No further comments, so I'm now closing this bug as fixed.