bug#54800: 28.1; calc: Cursor positioned at weird position in calc stack

[Christoph Arenz <tiga.arenz@web.de>]

On 09.04.22 15:32, Eli Zaretskii wrote:
>> Date: Sat, 9 Apr 2022 14:31:06 +0200
>> Cc: 54800@debbugs.gnu.org
>> From: Christoph Arenz <tiga.arenz@web.de>
>>
>>> I think the bug is actually off-by-one error, because the
>>> vertical-motion call doesn't take the header-line into account.  So I
>>> suggest the following patch instead, please see if it solves the
>>> problem:
>> Your patch solves the problem and shows maximum content of the stack
>> in the window.
> Thanks, I installed the fix on the emacs-28 branch.
>
I noticed that while the patch fixes the problem in most cases,
depending on the height of the calc stack window, there can be the case
that the cursor is not positioned on the top-of-stack symbol `.' but one
line
above, at the beginning of the line with the first stack entry.

This can be changed by using the number 4 instead of 3 in the patch.
Not sure if this is the best fix.

(vertical-motion (- 4 (window-height win)))