use Test::More tests => 7;

BEGIN {

if ($ENV{PERL_CORE}) {

chdir('t') if -d 't';

@INC = qw(../lib);

}

}

BEGIN { use_ok('NEXT') };

my $order = 0;

package A;

@ISA = qw/B C D/;

sub test { ::ok(++$order==1,"test A"); $_[0]->NEXT::UNSEEN::test; 1}

package B;

@ISA = qw/D C/;

sub test { ::ok(++$order==2,"test B"); $_[0]->NEXT::UNSEEN::test; 1}

package C;

@ISA = qw/D/;

sub test { ::ok(++$order==4,"test C"); $_[0]->NEXT::UNSEEN::test; 1}

package D;

sub test { ::ok(++$order==3,"test D"); $_[0]->NEXT::UNSEEN::test; 1}

package main;

my $foo = {};

bless($foo,"A");

eval{ $foo->test }

? pass("Correctly survives after C")

: fail("Shouldn't die on missing ancestor");

package Diamond::Base;

my $seen;

sub test {

$seen++ ? ::fail("Can't visit inherited test twice")

: ::pass("First diamond is okay");

shift->NEXT::UNSEEN::test;

}

package Diamond::Left; @ISA = qw[Diamond::Base];

package Diamond::Right; @ISA = qw[Diamond::Base];

package Diamond::Top; @ISA = qw[Diamond::Left Diamond::Right];

package main;

Diamond::Top->test;