public function testBuildForm() { $builder = $this->getMockBuilder('Symfony\Component\Form\Test\FormBuilderInterface')->getMock(); $builder->expects($this->atLeastOnce()) ->method('addEventSubscriber') ->with($this->isInstanceOf('Symfony\Component\Form\Extension\DataCollector\EventListener\DataCollectorListener')); $this->extension->buildForm($builder, array()); }