failure-suite.sh

#!/bin/bash

echo "Failure mode test suite for bash"
echo "  running bash $BASH_VERSION"

try() {
    trap 'echo FAILS' EXIT
    case $1 in
        simple)
            printf "  %-34s" "simple failed command"
            /bin/false
            ;;
        cmdsub)
            printf "  %-34s" "failed command substitution"
            local x=$( /bin/false )
            ;;

        pipe)
            printf "  %-34s" "failed pipe command input"
            /bin/false |cat
            ;;

        pipecmdsub)
            printf "  %-34s" "failed pipe command substitution"
            local x=$( /bin/false |cat )
            ;;
    esac
    echo "[ $? ]"
    trap '' EXIT
}

for flags in "" "-e" "-o pipefail" "-eo pipefail"; do
    echo
    [[ -z $flags ]] \
        && echo "Running with no error-catching:" \
        || echo "Running with \`set $flags\`:"
    for failure in simple cmdsub pipe pipecmdsub; do
        (
        [[ -n $flags ]] && eval "set $flags"
        try $failure
        )
    done
done