Re: right aligning a string, using display (space :align-to

[Eli Zaretskii <eliz@gnu.org>]

> Date: Fri, 20 Oct 2023 18:06:31 +0200
> From: martianhiatus@riseup.net
> 
> 
> > (concat
> >  (propertize " "
> >              'display
> >              `(space :align-to (- right
> >                                   ,(list (string-pixel-width stats)))))
> >  str)
> > 
> > and then it will work.
> 
> hi eli, thanks. i had tried to (list) the whole expression following :align-to.
> 
> it does work, but it still doesn't work with text-scaling. if i increase text-scale, my right-aligned string is broken over to the next line, same as when not using pixel-width alignment. if i decrease text scaling, my right-aligned string is further from the right margin.
> 
> i thought the two might be linked, but the behavior is the same.
> 
> do you have any ideas about how to not break :align-to while text scaling?

You assume that string-pixel-width takes text-scaling into account?  I
don't think it does; you should use window-text-pixel-size or
buffer-text-pixel-size instead.  That's because text-scaling is a
buffer-local feature, and string-pixel-width is not told which buffer
you have in mind.