@covers Symfony\Component\DependencyInjection\ContainerBuilder::createService
public function testCreateServiceClass() {
  $builder = new ContainerBuilder();
  $builder
    ->register('foo1', '%class%');
  $builder
    ->setParameter('class', 'stdClass');
  $this
    ->assertInstanceOf('\\stdClass', $builder
    ->get('foo1'), '->createService() replaces parameters in the class provided by the service definition');
}