Hi,
I am trying to use aur-sync with a split package and encountering some problems.
Regrettably I found the documention of both makepkg and aurutils a bit vague on split packages so I am unable to assess if this particular pacakge (https://aur.archlinux.org/pkgbase/distro-grub-themes) is set up incorrectly, aurutils sync alone cannot handle this, or the problem is between the screen and the chair.

For now, doing aur sync grub-theme-dell (ie one of the proper subpackages) pulls the base PKGBUILD just fine, but fails to build with a build: error: package group partially built. Running makepkg in the directory instead correctly builds all the subpackages. Meanwhile running aur build fails with the aformentioned error.
How should aur build be used with this kind of packages?