It seems srcpac, aura and yaourt all have functionality like this, but they use ABS for the PKGBUILD, which sadly lags behind official distro packages which means you'll often be building outdated packages if you use them. I couldn't find something which uses archlinux SVN instead.
- [arch-general] Automatizing makepkg Neven Sajko
- Re: [arch-general] Automatizing makepkg Eli Schwartz
- Re: [arch-general] Automatizing makepkg Neven Sajko
- Re: [arch-general] Automatizing makepkg Lukas Fleischer
- Re: [arch-general] Automatizing makepkg Neven Sajko

