check_fail(:revoke, :moderator_user, :moderator)
# this other user doesn't have moderator role, so this fails
check_fail(:revoke, :administrator_user, :moderator)
check_fail(:revoke, :moderator_user, :moderator)
# this other user doesn't have moderator role, so this fails
check_fail(:revoke, :administrator_user, :moderator)