Symfony2 FormIntegrationTestCase data is not changed in PRE_SUBMIT

Let's assume I have a form with two fields of type 'entity' and 'text'.

In my form I have PRE_SUBMIT listener, which changes values. It simply looks like this:

public function preSubmit(FormEvent $event)
{
    $data = $event->getData();

    $data['entityFiled'] = new SomeEntity();
    $data['textFiled'] = 'some_text';
    $event->setData($data);
}

The problem is in my FormIntegration test.

public function testSubmit($defaultData, $submittedData, $expectedData)
{
    $form = $this->factory->create($this->type, $defaultData, []);

    $this->assertEquals($defaultData, $form->getData());

    $form->submit($submittedData);
    $this->assertTrue($form->isValid());
    $this->assertEquals($expectedData, $form->getData());
}

Here $form->getData() should return properties with the updated in PRE_SUBMIT data, but only text field seems to be changed. Entity field is null there, as it is by default.

This happens only in FormIntegration test, functional tests works well.