root/branches/release-40/t/lib/Test/Deep/Cache/Simple.pm @ 2583

use strict;
use warnings;

package Test::Deep::Cache::Simple;
use Carp qw( confess );

use Scalar::Util qw( refaddr );

BEGIN
{
  if (grep /^weaken$/, @Scalar::Util::EXPORT_FAIL)
  {
    # we're running on a version of perl that has no weak refs, so we
    # just install a no-op sub for weaken instead of importing it
    *weaken = sub {};
  }
  else
  {
    Scalar::Util->import('weaken');
  }
}

sub new
{
        my $pkg = shift;

        my $self = bless {}, $pkg;

        return $self;
}

sub add
{
        my $self = shift;

        my ($d1, $d2) = @_;
        {
                local $SIG{__DIE__};

                # cannot weaken read only refs, no harm if we can't as they never
                # disappear
                eval{weaken($d1)};
                eval{weaken($d2)};
        }

        $self->{fn_get_key(@_)} = [$d1, $d2];
}

sub cmp
{
        my $self = shift;

        my $key = fn_get_key(@_);
        my $pair = $self->{$key};

        # are both weakened refs still valid, if not delete this entry
        if (ref($pair->[0]) and ref($pair->[1]))
        {
                return 1;
        }
        else
        {
                delete $self->{$key};
                return 0;
        }
}

sub absorb
{
        my $self = shift;

        my $other = shift;

        @{$self}{keys %$other} = values %$other;
}

sub fn_get_key
{
        return join(",", sort (map {refaddr($_)} @_));
}
1;