Subject: bug#34476: fluffy whitespace in the mode-line, despite it running off the screen

From: Lars Ingebrigtsen <[email-masked]>
Date: Sat, 08 Aug 2020 16:16:04 +0200

Eli Zaretskii <[email-masked]> writes:

> Note a few subtle issues:
>
>  . I've limited the feature to the mode line; programs that set
>    header-line and tab-line either don't want this, or should format
>    those lines to not waste screen space to begin with;

Yup.

>  . I've refrained from squeezing spaces if they have non-default
>    faces, on the assumption that those spaces are significant -- the
>    result is that the trailing spaces of the buffer name are not
>    squeezed, but I think we have no choice here, as down that path
>    lies madness (think a mode line that plays some fancy games with
>    font sizes).

Right, so with the patch, I get these two mode lines (with and without
compaction): 

There's four spaces between *scratch* and All because they have
different faces...  which makes me wonder why there's trailing spaces in
the buffer name at all, instead of just three spaces after the buffer
name in the mode line format?  But that's a different issue; the patch
looks great.

There's also the question of allowing a value of `long' to
mode-line-compact -- which would only compact the mode line if it's
longer than the window width.  Would that be difficult to add?

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