Program Repair Shop 63

Testing undocumented behavior

        my $baz_b = Baz->new;
        is( $baz_b->add_observer( \&observer_c ), 1 );
        $baz_b->yell;
        
        is( $observations[3], "Observation C from [Baz]" );
        is( $observations[4], "Observation B from [Baz]" );
        is( $observations[5], "Observation A from [Baz]" );
        @observations = ();
        
        my $baz_b = Baz->new;
        is( $baz_b->add_observer( \&observer_c ), 1 );
        $baz_b->yell;
        
        @observations = sort @observations;
        is( $observations[0], "Observation A from [Baz]" );
        is( $observations[1], "Observation B from [Baz]" );
        is( $observations[2], "Observation C from [Baz]" );
        use Test::Deep;
        
        cmp_deeply(\@observations,
          bag(map "Observation $_ from [Baz]", qw(A B C)));

but we didn't have it then.)