Subject: bug#33232: `gnus-summary-line-format' padding doesn’t work in gui when there are multiple-column-width characters

From: Lars Ingebrigtsen <[email-masked]>
Date: Sat, 22 Jun 2019 15:19:16 +0200

"Garreau, Alexandre" <[email-masked]> writes:

> Given this (rectangular) excerpt from my bug-gnu-emacs summary:
>> …01-nov…[-> [email-masked]        ] bug#33224: `message-simpli…
>> …01-nov…[Noam Postavsky                  ] bug#33225: [debbugs.el] Do…
>> …01-nov…[-> Noam Postavsky               ]  bug#33225: [debbugs.el] D…
>> …01-nov…[積丹尼 Dan Jacobson             ] bug#33226: chromium, firef…
>
> On my system (Debian, with Xorg, i3, GUI Emacs), the last line has its
> “]” sooner than the others.  This is because `gnus-correct-length'
> (along with `char-width') says each of the first three characters is
> two-columns wide: but under GUI, this is untrue, as these three
> collectively form exactely 5 columns (and not six, as would calculate
> `gnus-correct-length').

Yes, using characters from a mixture of fonts that have widths that do
not add up to multiples of each other just isn't supported by Gnus.  To
do so would require a rewrite of the machinery that generates the
buffers, and gnus-summary-line-format would have to be obsoleted and
something new that uses display properties with align-to could be used.

So I'm closing this bug report as a "wontfix".

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no