This is exactly what we've been preparing for. Don't use yaourt, and read those diffs. I know a lot of people don't do this, but it's important.
It has options to configure it to do everything automatically, but you have to actively go in and set it so.
if [ -z "$1" ]; then echo "No package name specified."; exit; fi
mkdir -p $1
cd $1
wget -q "https://aur.archlinux.org/cgit/aur.git/snapshot/$1.tar.gz"
tar xzf $1.tar.gz
cd $1
makepkg -sf
read -n 1 -s -p "Press any key to continue..."
echo -e "\n"
sudo pacman -U --noconfirm --needed $1*pkg.tar.xz