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#!/usr/bin/perl

use strict;
use warnings;

require q(./test.pl); plan(tests => 10);

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

=pod

This tests the classic diamond inheritance pattern.

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

=cut

{
    package Diᚪၚd_A;
    use mro 'c3'; 
    sub ᴮaȐ { 'Diᚪၚd_A::ᴮaȐ' }        
    sub 바ź { 'Diᚪၚd_A::바ź' }
}
{
    package Diᚪၚd_B;
    use base 'Diᚪၚd_A';
    use mro 'c3';    
    sub 바ź { 'Diᚪၚd_B::바ź => ' . (shift)->next::method() }         
}
{
    package Diᚪၚd_C;
    use mro 'c3';    
    use base 'Diᚪၚd_A';     
    sub ᕘ { 'Diᚪၚd_C::ᕘ' }   
    sub buƵ { 'Diᚪၚd_C::buƵ' }     
    
    sub woz { 'Diᚪၚd_C::woz' }
    sub maᐇbʚ { 'Diᚪၚd_C::maᐇbʚ' }         
}
{
    package Diᚪၚd_D;
    use base ('Diᚪၚd_B', 'Diᚪၚd_C');
    use mro 'c3'; 
    sub ᕘ { 'Diᚪၚd_D::ᕘ => ' . (shift)->next::method() } 
    sub ᴮaȐ { 'Diᚪၚd_D::ᴮaȐ => ' . (shift)->next::method() }   
    sub buƵ { 'Diᚪၚd_D::buƵ => ' . (shift)->바ź() }  
    sub fuz { 'Diᚪၚd_D::fuz => ' . (shift)->next::method() }  
    
    sub woz { 'Diᚪၚd_D::woz can => ' . ((shift)->next::can() ? 1 : 0) }
    sub noz { 'Diᚪၚd_D::noz can => ' . ((shift)->next::can() ? 1 : 0) }

    sub maᐇbʚ { 'Diᚪၚd_D::maᐇbʚ => ' . ((shift)->maybe::next::method() || 0) }
    sub ᒧyベ { 'Diᚪၚd_D::ᒧyベ => ' .    ((shift)->maybe::next::method() || 0) }

}

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->ᕘ, 'Diᚪၚd_D::ᕘ => Diᚪၚd_C::ᕘ', '... skipped B and went to C correctly');
is(Diᚪၚd_D->ᴮaȐ, 'Diᚪၚd_D::ᴮaȐ => Diᚪၚd_A::ᴮaȐ', '... skipped B & C and went to A correctly');
is(Diᚪၚd_D->바ź, 'Diᚪၚd_B::바ź => Diᚪၚd_A::바ź', '... called B method, skipped C and went to A correctly');
is(Diᚪၚd_D->buƵ, 'Diᚪၚd_D::buƵ => Diᚪၚd_B::바ź => Diᚪၚd_A::바ź', '... called D method dispatched to , different method correctly');
eval { Diᚪၚd_D->fuz };
like($@, qr/^No next::method 'fuz' found for Diᚪၚd_D/u, '... cannot re-dispatch to a method which is not there');
is(Diᚪၚd_D->woz, 'Diᚪၚd_D::woz can => 1', '... can re-dispatch figured out correctly');
is(Diᚪၚd_D->noz, 'Diᚪၚd_D::noz can => 0', '... cannot re-dispatch figured out correctly');

is(Diᚪၚd_D->maᐇbʚ, 'Diᚪၚd_D::maᐇbʚ => Diᚪၚd_C::maᐇbʚ', '... redispatched D to C when it exists');
is(Diᚪၚd_D->ᒧyベ, 'Diᚪၚd_D::ᒧyベ => 0', '... quietly failed redispatch from D');