source: vendor/bash/3.1-p17/tests/set-e-test

if : ; then
        set -e
        N=95
        while :; do
                # expr returns 1 if expression is null or 0
                set +e
                N_MOD_100=`expr $N % 100`
                set -e
                echo $N_MOD_100
                N=`expr $N + 1`
                if [ $N -eq 110 ]; then
                        break
                fi
        done
        set +e
fi

(
set -e
false
echo bad
)
echo $?

x=$(
set -e
false
echo bad
)
echo $? $x

# command subst should not inherit -e
set -e
echo $(false; echo ok)

if set +e
then
        false
fi
echo hi

set -e

# a failing command in the compound list following a while, until, or
# if should not cause the shell to exit

while false; do
        echo hi
done
echo while succeeded

x=1
until (( x == 4 )); do
        x=4
done
echo until succeeded: $x

if false; then
        echo oops
fi
echo if succeeded

# failing commands that are part of an AND or OR list should not
# cause the shell to exit
false && echo AND list failed
echo AND list succeeded

false || echo OR list succeeded

! false
echo ! succeeded

# make sure eval preserves the state of the -e flag and `!' reserved word
set -e
if eval false; then
        echo oops
fi
echo eval succeeded

! eval false
echo ! eval succeeded -- 1

! eval '(exit 5)'
echo ! eval succeeded -- 2