bug#51155: 29.0.50; Incorrect weight used in Cantarell VF

[Eli Zaretskii]

> From: Utkarsh Singh <utkarsh190601@gmail.com>
> Date: Tue, 12 Oct 2021 16:45:41 +0530
> 
> On 2021-09-21, Arch Linux updated their Cantarell font package, which
> removed classic font with variable fonts.  According to Jan Alexander
> Steffens (package maintainer):
> 
> > Yeah, we only packaged VF because upstream requested to either package
> > the classic fonts *or* the variable font. The VF is more powerful as
> > it not just contains all the classic weights but can also interpolate
> > between them.
> 
> But with these changes Emacs in now unable to distinguish between light
> and regular weights.  To reproduce the bug you would have to:
> 
> 1. Install latest version of font from upstream:
> <https://gitlab.gnome.org/GNOME/cantarell-fonts>
> 
> 2. Evaluate in "emacs -Q" session:
> (progn
>   (set-face-attribute 'variable-pitch nil :family "Cantarell" :weight 
> 'regular)
>   (face-font 'variable-pitch))
> 
> Also see bug report on Arch Linux bug tracker:
> <https://bugs.archlinux.org/task/72212>

What are the numerical values of weight in these fonts?