-readonly this_file="$(readlink -f -- "${BASH_SOURCE[0]}")"
-script_dir="${this_file%/*}"
-# shellcheck source=./bash-trace
-source "${script_dir}/bash-trace"
-cd $script_dir
-source "${script_dir}/bash-trace"
+if ! test "$BASH_VERSION"; then echo "error: shell is not bash" >&2; exit 1; fi
+shopt -s inherit_errexit 2>/dev/null ||: # ignore fail in bash < 4.4
+set -eE -o pipefail
+trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" exit status: $?, PIPESTATUS: ${PIPESTATUS[*]}" >&2' ERR