Only show log info when something has been logged

    echo "BUILD FAILED"

    echo

    echo "Inspect or clean up the working tree at ${TEMP_PATH}"

    if file_is_not_empty "$LOG_PATH"; then

      echo "Results logged to ${LOG_PATH}"

      echo

      echo "Last 10 log lines:"

    tail -n 10 $LOG_PATH

      tail -n 10 "$LOG_PATH"

    fi

  } >&3

  exit 1

}

file_is_not_empty() {

  local filename="$1"

  local line_count="$(wc -l "$filename" 2>/dev/null || true)"

  if [ -n "$line_count" ]; then

    words=( $line_count )

    [ "${words[0]}" -gt 0 ]

  else

    return 1

  fi

}

install_package() {

  install_package_using "tarball" 1 $*

}