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

[Lars Ingebrigtsen]

Eli Zaretskii <eliz@gnu.org> writes:

> You are comparing the number of characters with the window-body width,
> but the latter is measured in units of the frame's canonical character
> width, i.e. the average width of the default face's font.  If someone
> modifies the mode-line face to use a font of a different size, or even
> has enough wide characters there to violate the "1 character = 1
> column" assumption, that test will produce either truncated mode-line
> string or will unnecessarily squeeze spaces from it.

Yup.  I was also not quite sure of the selected_window itself -- can the
mode line be updated while another window is selected?  But I tried
various scenarios, and I couldn't get it to pick the wrong window to do
the computation on.  So perhaps that bit is OK?

> I understand the difficulty of doing TRT, but perhaps we should at
> least document this limitation, so that users don't expect too much
> from this feature, and we don't get bug reports that will be hard to
> fix?

Yup; will do.

-- 
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   bloggy blog: http://lars.ingebrigtsen.no