bug#54450: 29.0.50; redisplay--pre-redisplay-functions issue

[Ergus]

On Fri, Mar 18, 2022 at 08:54:00PM +0200, Eli Zaretskii wrote:
> > Date: Fri, 18 Mar 2022 20:38:18 +0200
> > From: Eli Zaretskii <eliz@gnu.org>
> > Cc: 54450@debbugs.gnu.org
> >
> > > Yes, this could solve the issue for the region, but not in general for
> > > redisplay--update-cursor-face-highlight which was the initial problem
> > > with Juri's code. Same for any other function that goes into the
> > > pre-redisplay-functions hook.
> >
> > I asked for a test case, and this is what you gave me.
> >
> > If there's another test case, please show it.
>
> But before you do, please try the alternative patch below:
>
> diff --git a/src/xdisp.c b/src/xdisp.c
> index 5cb5839..6d8d4aa 100644
> --- a/src/xdisp.c
> +++ b/src/xdisp.c
> @@ -13211,7 +13211,8 @@ prepare_menu_bars (void)
>               struct window *w = XWINDOW (this);
>               if (w->redisplay
>                   || XFRAME (w->frame)->redisplay
> -                 || XBUFFER (w->contents)->text->redisplay)
> +                 || XBUFFER (w->contents)->text->redisplay
> +                 || w->last_point != marker_position (w->pointm))
>                 {
>                   windows = Fcons (this, windows);
>                 }

Yes, now this seems to solve the issue for the two use cases described.

Thanks,
Ergus