[arch-general] Best way for PKGBUILD to depend on another PKGBUILD (not a package)

[Nowaker]

Hi,

Today on AUR I published coreutils-static package [1], a statically 
compiled variant of coreutils with --prefix=/rescue.

coreutils depends on libattr and libcap. Because of the nature of static 
compilation libattr.a and libcap.a files are needed during the build. 
My package defines PKGBUILDs from [core] repo as source=(), performs 
`makepkg`, and provides -L for coreutils make during build(). [2]

I pretty much like this idea because PKGBUILDs are ready to use.
I don't need to define attr and libcap tar.gz releases as my package 
source=() and compile them by hand in build() which would be, more or 
less, a copy-paste. (pacman-static in AUR [3] does a copy-paste)

The question: is this the best way for PKGBUILD to depend on another 
PKGBUILD? Are there any better solutions? And if this approach is 
reasonable, are there any ways to improve it? Especially the PKGBUILD 
code for -L, I don't quite like it.

Thanks.

[1] https://aur.archlinux.org/packages/coreutils-static
[2] https://aur.archlinux.org/packages/co/coreutils-static/PKGBUILD
[3] https://aur.archlinux.org/packages/pacman-static/

-- 
Kind regards,
Damian Nowak
StratusHost
www.AtlasHost.eu