if [ -e "$NIX_ATTRS_SH_FILE" ]; then . "$NIX_ATTRS_SH_FILE"; elif [ -f .attrs.sh ]; then . .attrs.sh; fi
source $stdenv/setup
echo "Cloning Fossil $url [$rev] into $out"

# Fossil, bless its adorable little heart, wants to write global configuration
# to $HOME/.fossil. AFAICT, there is no way to disable this functionality.
# Instead, we'll let it write to the build directory.
export HOME=$(pwd)

# We must explicitly set the admin user for the clone to something reasonable.
fossil clone -A nobody "$url" fossil-clone.fossil

mkdir fossil-clone
WORKDIR=$(pwd)
mkdir $out
pushd $out
fossil open "$WORKDIR/fossil-clone.fossil" "$rev"
popd

# Just nuke the checkout file.
rm $out/.fslckout