+ is($sig, getsig $wiz2, 'retrieved wizard signature is correct');
+
+ my $wiz3 = eval { wizard sig => [ ] };
+ like($@, qr/Invalid\s+numeric\s+signature\s+at\s+\Q$0\E/, 'non numeric signature croaks');
+ is($wiz3, undef, 'non numeric signature doesn\'t return anything');