# $FreeBSD: releng/12.1/bin/sh/tests/execution/set-x1.0 222882 2011-06-08 21:58:19Z jilles $

key='must_contain_this'
{ r=`set -x; { : "$key"; } 2>&1 >/dev/null`; } 2>/dev/null
case $r in
*"$key"*) true ;;
*) false ;;
esac