# do all of these in subshells since it's supposed to error out
# (set argv0 to "SHELL" to avoid "/path/to/shell: blah" in error messages)

# first try some invalid patterns
#"$THIS_SH" -c 'echo ${?}' SHELL -- this is valid as it's the same as $?
"$THIS_SH" -c 'echo ${:?}' SHELL

# then some funky ones
# note: bash prints 1 - treats it as "length of $#"
"$THIS_SH" -c 'echo ${#?}' SHELL
# bash prints 0
"$THIS_SH" -c 'echo ${#:?}' SHELL

# now some valid ones
export msg_unset="unset!"
export msg_null_or_unset="null or unset!"

echo ====
"$THIS_SH" -c 'set --; echo _$1' SHELL
"$THIS_SH" -c 'set --; echo _${1?}' SHELL
"$THIS_SH" -c 'set --; echo _${1:?}' SHELL
"$THIS_SH" -c 'set --; echo _${1?message1}' SHELL
"$THIS_SH" -c 'set --; echo _${1:?message1}' SHELL
"$THIS_SH" -c 'set --; echo _${1?$msg_unset}' SHELL
"$THIS_SH" -c 'set --; echo _${1:?$msg_null_or_unset}' SHELL

echo ====
"$THIS_SH" -c 'set -- aaaa; echo _$1' SHELL
"$THIS_SH" -c 'set -- aaaa; echo _${1?}' SHELL
"$THIS_SH" -c 'set -- aaaa; echo _${1:?}' SHELL
"$THIS_SH" -c 'set -- aaaa; echo _${1?word}' SHELL
"$THIS_SH" -c 'set -- aaaa; echo _${1:?word}' SHELL
"$THIS_SH" -c 'set -- aaaa; echo _${1?$msg_unset}' SHELL
"$THIS_SH" -c 'set -- aaaa; echo _${1:?$msg_null_or_unset}' SHELL

echo ====
"$THIS_SH" -c 'unset f; echo _$f' SHELL
"$THIS_SH" -c 'unset f; echo _${f?}' SHELL
"$THIS_SH" -c 'unset f; echo _${f:?}' SHELL
"$THIS_SH" -c 'unset f; echo _${f?message3}' SHELL
"$THIS_SH" -c 'unset f; echo _${f:?message3}' SHELL
"$THIS_SH" -c 'unset f; echo _${f?$msg_unset}' SHELL
"$THIS_SH" -c 'unset f; echo _${f:?$msg_null_or_unset}' SHELL

echo ====
"$THIS_SH" -c 'f=; echo _$f' SHELL
"$THIS_SH" -c 'f=; echo _${f?}' SHELL
"$THIS_SH" -c 'f=; echo _${f:?}' SHELL
"$THIS_SH" -c 'f=; echo _${f?word}' SHELL
"$THIS_SH" -c 'f=; echo _${f:?message4}' SHELL
"$THIS_SH" -c 'f=; echo _${f?$msg_unset}' SHELL
"$THIS_SH" -c 'f=; echo _${f:?$msg_null_or_unset}' SHELL

echo ====
"$THIS_SH" -c 'f=fff; echo _$f' SHELL
"$THIS_SH" -c 'f=fff; echo _${f?}' SHELL
"$THIS_SH" -c 'f=fff; echo _${f:?}' SHELL
"$THIS_SH" -c 'f=fff; echo _${f?word}' SHELL
"$THIS_SH" -c 'f=fff; echo _${f:?word}' SHELL
"$THIS_SH" -c 'f=fff; echo _${f?$msg_unset}' SHELL
"$THIS_SH" -c 'f=fff; echo _${f:?$msg_null_or_unset}' SHELL