package X;

use base qw(Test::Class);
use Test::More;
use Test::MockClass;

sub setup : Test(setup) {
  my ($self) = @_;
  my $mockClass = Test::MockClass->new('DateTime');
  $mockClass->addMethod('now', sub {'XXXX'});
}

sub test : Test {
  my ($self) = @_;
  ok(DateTime->now);
  diag(DateTime->now);
}

1;

package Y;

use base qw(Test::Class);
use Test::More;
use DateTime;

sub test : Test {
  my ($self) = @_;
  ok(DateTime->now);
  diag(DateTime->now);
}

1;

package Z;

use Test::Class;

Test::Class->runtests;

1;