#!/usr/bin/perl

use strict;
use warnings;

use Test::More tests => 1;

=pod

This example is take from: http://www.python.org/2.3/mro.html

"Serious order disagreement" # From Guido
class O: pass
class X(O): pass
class Y(O): pass
class A(X,Y): pass
class B(Y,X): pass
try:
    class Z(A,B): pass #creates Z(A,B) in Python 2.2
except TypeError:
    pass # Z(A,B) cannot be created in Python 2.3

=cut

eval q{ 
    {
        package X;
        use Class::C3;

        package Y;
        use Class::C3;    

        package XY;
        use Class::C3;
        use base ('X', 'Y');

        package YX;
        use Class::C3;
        use base ('Y', 'X');

        package Z;
        eval 'use Class::C3' if $Class::C3::C3_IN_CORE;
        use base ('XY', 'YX');
    }

    Class::C3::initialize();

    # now try to calculate the MRO
    # and watch it explode :)
    Class::C3::calculateMRO('Z');
};
#diag $@;
like($@, qr/Inconsistent hierarchy /, '... got the right error with an inconsistent hierarchy');