search backward for a directory from current path

find-previous-dir.sh

#!/bin/bash
die () {
    echo >&2 "$@"
    exit 1
}

[ "$#" -eq 1 ] || die "1 argument required, $# provided"

DIRNAME=$1

while [ ! -d ${DIRNAME} ] && [ "${PWD}" != "/" ]; do
  cd ..
done

[ "${PWD}" = "/" ] && die "dir '${DIRNAME}'' not found!"

echo "${PWD}/$DIRNAME"