cdgem

function cdgem {
  bundle="$(bundle show $1)"
  gem="$(gem which $1 2>/dev/null | grep '^/')"
  for gem_dir in "${bundle}" "${gem:h}"; do
    if [[ -d "${gem_dir}" ]]; then
      cd "${gem_dir}"
      return
    fi
  done
  print 'not found'
}