Subject: bug#70386: 30.0.50; (recenter 0 t) does not put point on top of the window

From: Eli Zaretskii <[email-masked]>
Date: Sun, 12 May 2024 12:19:40 +0300

> From: Ihor Radchenko <[email-masked]>
> Cc: [email-masked], [email-masked]
> Date: Sun, 12 May 2024 07:19:51 +0000
> 
> Eli Zaretskii <[email-masked]> writes:
> 
> > It is still very much unpredictable: sometimes shows the last line at
> > the window's top, sometimes doesn't.
> 
> Let's try a slightly different recipe:
> 
> 1. emacs -Q
> 2. Insert
> (progn
>   (require 'pixel-scroll)
>   (pixel-scroll-precision-interpolate
>    (* -1 (line-pixel-height)) nil 1)
>   (recenter 0 t))
> 3. Move point to "progn"
> 4. M-x eval-buffer

Still unpredictable.  Sometimes point ends up on progn with
window-start being 1 as at the beginning, sometimes I see the
"recenter" line at the top line with point at EOB (i.e. below that
line).

Why do you think some minor modifications of the recipe should affect
the results?