bug#23574: 24.5; Overzealous underlining in emacs-nox

[Noam Postavsky]

On Tue, Jun 7, 2016 at 11:55 AM, Eli Zaretskii <eliz@gnu.org> wrote:
>> From: Noam Postavsky <npostavs@users.sourceforge.net>
>> Date: Mon, 6 Jun 2016 20:18:06 -0400
>> Cc: Colin Woodbury <cwoodbury@azavea.com>, martin rudalics 
>> <rudalics@gmx.at>, 23574@debbugs.gnu.org,
>>       John Mastro <john.b.mastro@gmail.com>
>>
>> I think it makes sense to not do the face extension by default.
>
> Not even for the background color?  Or are you talking only about the
> underline?

Well, I was thinking mostly about underlining, but imagining a
scenario with paper again, if I'm highlighting text with a marker, I
wouldn't go to edge of the page there either.

For some applications, the intention is to colour a whole block, not
just the text. So I think it's better to let the code making the faces
have a way to indicate which scenario is intended rather than relying
on user customization.

>
>> For the case I mentioned earlier, magit isn't actually underlining
>> text, it just wants to make some horizontal lines. It would be nice to
>> have some way to ask the display engine to do this directly.
>
> There's a way of doing that which we use in the VC commit log buffer,
> I believe it uses the line-height property.  (I thought magit was
> using that as well, no?)

Yes, and it caused some problems with cursor movement that you weren't
so happy about fixing.