bug#59802: 30.0.50; Checkbox button not rendered

[Stephen Berman <stephen.berman@gmx.net>]

On Sat, 10 Dec 2022 15:49:21 +0200 Eli Zaretskii <eliz@gnu.org> wrote:

>> From: Stephen Berman <stephen.berman@gmx.net>
>> Cc: Manuel Giraud <manuel@ledu-giraud.fr>,  59802@debbugs.gnu.org
>> Date: Fri, 09 Dec 2022 14:41:27 +0100
>>
>> > What happens if you manually create a buffer with the checkbox and
>> > text following it -- does the problem happen in that case as well?
>>
>> It does for me: the attached image shows four buffers containing the
>> checkbox.svg and checkbox.xpm images from /etc/images.  The leftmost
>> buffer shows the default font size, the other buffers show increases of
>> the font size successively by two steps with `C-x C-+'.
>>
>> (The rightmost buffer shows another oddity: the line number is
>> supposedly 47.  This number appears when the cursor moves from 'T' to
>> 'e'.  This also happens in the other buffers, but only those with
>> increased font size show line number 47; in the leftmost buffer, it
>> shows line number 27.)
>
> I couldn't reproduce any of this.  But since you didn't say how you
> created that display, exactly, it's possible that I tried something
> different.
>
> Can you show the Lisp which you used?

I create buffer "a" by typing this (with emacs -Q):

C-x b a
M-: (insert-image-file "path/to/emacs/etc/images/checked.svg")
C-f
M-: (insert-image-file "path/to/emacs/etc/images/checked.xpm")
C-f
Test

To create buffer "+2" I type `C-x h M-w' in buffer "a", and then type
`C-x b +2 C-y'.  However, this results in only the image checked.svg
being displayed in "+2", but with point not before but after the image,
so then I insert the image checked.xpm and the string "Test" as above.
Then I typed `C-x C-+' twice.  I create buffers "+4" and "+6" likewise
(typing `C-x C-+' four and six times, respectively).

Concerning the line number display, after inserting checked.svg in
buffer "a" and typing `C-f' the mode line displays "L1".  After
inserting checked.xpm as above, the mode line displays "L7", and after
typing `C-f T' it displays "L27" and remains like that while and after
typing "est".  After typing `C-y' in buffer "+2" (which displays only
checked.svg), the mode line displays "L27" and stays like that after
inserting checked.xpm and typing `C-f'.  But as soon as I type "T" the
mode line displays "L47".  (So I was mistaken in saying the line number
display changes by changing the font size.)

Steve Berman