Fonts do not work with multiple profiles (fontconfig) and a proposed workaround

["Todor Kondić" <tk.code@protonmail.com>]

Here's my experience with guix-as-a-package-manager, fontconfig and multiple profiles.


If fonts are installed in a profile different than the default one, applications do not pick them up out of the box. I.e. icecat shows characters as squares and you cannot select a cool non standard font in your GTK Emacs.

After digging into this matter, I concluded that the culprit is the main config file situated in some-nondefault-guix-profile/etc/fonts/fonts.conf

Here's a snippet:
-------------------------
<!-- Font directory list -->

	<dir>/gnu/store/7y3lvk3xf4im8n44337mc6y0ccysvfia-font-dejavu-2.37/share/fonts</dir>
	<dir>~/.guix-profile/share/fonts</dir> <dir>/run/current-system/profile/share/fonts</dir>
	<dir prefix="xdg">fonts</dir>
	<!-- the following element will be removed in the future -->
	<dir>~/.fonts</dir>
---------------------------

Clearly, some-nondefault-guix-profile/share/fonts is not among the list of dirs that are searched for font definitions. I'd call this a bug, but maybe it's by design. Still, shouldn't guix package definitions respect the -p flag to package command?


Anyway, the workaround is the following. See this snippet of the same config file,
----------------------------
<!--
  Load local system customization file
-->
	<include ignore_missing="yes">conf.d</include>

<!-- Font cache directory list -->
-----------------------------

This means it includes the conf files in ...profile/etc/conf.d. The README file reveals that 5?-*.conf files are used for additional customisation. This makes 50-user.conf particularly interesting. And, here it is ...

-----------------------------
<include ignore_missing="yes" prefix="xdg">fontconfig/conf.d</include>
	<include ignore_missing="yes" prefix="xdg">fontconfig/fonts.conf</include>
	<!-- the following elements will be removed in the future -->
	<include ignore_missing="yes" deprecated="yes">~/.fonts.conf.d</include>
	<include ignore_missing="yes" deprecated="yes">~/.fonts.conf</include>
-----------------------------

Apparently , ~/.config/fontconfig/fonts.conf (xdg prefix being ~/.config) is the place to add some more config

After creating ~/.config/fontconfig/fonts.conf with the following content

-----------------------------
<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<!-- /etc/fonts/fonts.conf file to configure system font access -->
<fontconfig>
	<its:rules xmlns:its="http://www.w3.org/2005/11/its" version="1.0">
		<its:translateRule translate="no" selector="/fontconfig/*[not(self::description)]"/>
	</its:rules>

	<description>Default configuration file</description>


<!-- Font directory list -->
        <dir>~/.guix-pillars/pillar/share/fonts</dir>

</fontconfig>

------------------------------

and running fc-cache -rvf the fontconfig-aware programs were able to select fonts from the non-default guix profile.


Hope this helps (me again in six monts from now)!

T