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#!/usr/bin/perl
use strict;
use warnings;
use Test::More tests => 29;
BEGIN {
use_ok('MooseX::AttributeHelpers');
}
package Subject;
use Moose::Role;
use MooseX::AttributeHelpers;
has observers => (
metaclass => 'Collection::Array',
is => 'ro',
isa => 'ArrayRef[Observer]',
auto_deref => 1,
default => sub { [] },
provides => { 'push' => 'add_observer', count => 'count_observers' }
);
sub notify {
my ($self) = @_;
foreach my $observer ( $self->observers() ) {
$observer->update($self);
}
}
###############################################################################
package Observer;
use Moose::Role;
requires 'update';
###############################################################################
package Counter;
use Moose;
use MooseX::AttributeHelpers;
with 'Subject';
has count => (
metaclass => 'Counter',
is => 'ro',
isa => 'Int',
default => 0,
provides => {
inc => 'inc_counter',
dec => 'dec_counter',
}
);
after 'inc_counter','dec_counter' => sub {
my ($self) = @_;
$self->notify();
};
###############################################################################
package Display;
use Test::More;
use Moose;
with 'Observer';
sub update {
my ( $self, $subject ) = @_;
like $subject->count, qr{^-?\d+$}, 'Observed number ' . $subject->count;
}
###############################################################################
package main;
my $count = Counter->new();
ok($count->can('add_observer'), 'add_observer method added');
ok($count->can('count_observers'), 'count_observers method added');
ok($count->can('inc_counter'), 'inc_counter method added');
ok($count->can('dec_counter'), 'dec_counter method added');
$count->add_observer( Display->new() );
is($count->count_observers, 1, 'Only one observer');
is($count->count, 0, 'Default to zero');
$count->inc_counter;
is($count->count, 1, 'Increment to one ');
$count->inc_counter for (1 .. 6);
is($count->count, 7, 'Increment up to seven');
$count->dec_counter;
is($count->count, 6, 'Decrement to 6');
$count->dec_counter for (1 .. 5);
is($count->count, 1, 'Decrement to 1');
$count->dec_counter for (1 .. 2);
is($count->count, -1, 'Negative numbers');
$count->inc_counter;
is($count->count, 0, 'Back to zero');
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