Icon caches should be generated for directories under $out/share/icons, as the comments mention, but it is done for files as well which does not make the build fail but results in files under $out/share/icons being turned into empty directories, see /run/current-system/sw/share/icons/gnome-logo-text.svg as an example.
the conversion procedure is simple:
- find all things that look like options, ie calls to either `mkOption`
or `lib.mkOption` that take an attrset. remember the attrset as the
option
- for all options, find a `description` attribute who's value is not a
call to `mdDoc` or `lib.mdDoc`
- textually convert the entire value of the attribute to MD with a few
simple regexes (the set from mdize-module.sh)
- if the change produced a change in the manual output, discard
- if the change kept the manual unchanged, add some text to the
description to make sure we've actually found an option. if the
manual changes this time, keep the converted description
this procedure converts 80% of nixos options to markdown. around 2000
options remain to be inspected, but most of those fail the "does not
change the manual output check": currently the MD conversion process
does not faithfully convert docbook tags like <code> and <package>, so
any option using such tags will not be converted at all.
It's a quick approximation to unblock unstable channels after #48116.
This commit isn't ideal, as I suspect most wayland users won't have
xserver.enable, so they will lose the icon cache in case they had gtk
in system path (otherwise they didn't get cache anyway).
I considered using environment.noXlibs, but the nixos tests installing
headless systems do *not* get that option, so we would still be pulling
gtk in many cases where it's clearly not desired. We need to design
this more carefully.