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#!./perl

use strict;
use warnings;
use utf8;
use open qw( :utf8 :std );

require q(./test.pl); plan(tests => 4);

=pod

This tests the classic diamond inheritance pattern.

   <A>
  /   \
<B>   <C>
  \   /
   <D>

=cut

{
    package Diᚪၚd_A;
    sub hèllò { 'Diᚪၚd_A::hèllò' }
}
{
    package Diᚪၚd_B;
    use base 'Diᚪၚd_A';
}
{
    package Diᚪၚd_C;
    use base 'Diᚪၚd_A';     
    
    sub hèllò { 'Diᚪၚd_C::hèllò' }
}
{
    package Diᚪၚd_D;
    use base ('Diᚪၚd_B', 'Diᚪၚd_C');
    use mro 'c3';
}

ok(eq_array(
    mro::get_linear_isa('Diᚪၚd_D'),
    [ qw(Diᚪၚd_D Diᚪၚd_B Diᚪၚd_C Diᚪၚd_A) ]
), '... got the right MRO for Diᚪၚd_D');

is(Diᚪၚd_D->hèllò, 'Diᚪၚd_C::hèllò', '... method resolved itself as expected');
is(Diᚪၚd_D->can('hèllò')->(), 'Diᚪၚd_C::hèllò', '... can(method) resolved itself as expected');
is(UNIVERSAL::can("Diᚪၚd_D", 'hèllò')->(), 'Diᚪၚd_C::hèllò', '... can(method) resolved itself as expected');