_cdup() {
	local dir=$1; shift
	local targets=("$@")
	for target in $targets; do
		if [[ -e $dir/$target ]]; then
			cd $dir
			return 0
		fi
	done
	if [[ $dir == "/" ]]; then return 1
	else _cdup ${dir:h} ${targets[@]}
	fi
}

cdup() {
	if [[ ${#@} -gt 0 ]]; then _cdup ${PWD:h} "$@"
	else _cdup ${PWD:h} .git .hg package.json build.sbt
	fi
}