bug#65990: 29.1; show-paren-mode should not highlight line-prefix area

[Stefan Kangas]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: awrhygty@outlook.com
>> Date: Fri, 15 Sep 2023 18:26:12 +0900
>>
>>
>> Evaluate the form below,
>> the blank area on the left of the open parensis is highlighted,
>> while the blank area on the left of the close parensis is not.
>> Then type 'C-l C-l' to make the close parensis placed at the window
>> start, the area on the left of the close parensis is highlighted.
>>
>> (let ((buf (generate-new-buffer "*temp*")))
>>   (switch-to-buffer buf)
>>   (insert (propertize "(x\n)" 'line-prefix '(space :width 8))))
>
> Normally, none of the line-prefix should be highlighted.  And that is
> what happens when the show-paren face is anywhere but at the first
> visible character in the window.  When the face _is_ on the first
> visible character in the window, it is not clear whether the face
> should be considered as starting before the window or not; the current
> display code considers it to start before the window-start.
>
> I tend to close this bug as wontfix, since it seems to happen in rare
> situations, and fixing it will likely be messy.  If you can show that
> it happens in more than just these rare cases, or if you have any
> suggestions for how to fix that or even can just point to the code
> which causes this, I might change my mind.
>
> Thanks.

No further comments within 3 months, so I'm closing this bug.