Tests field handler.
public function testDataField() {
// But some random values into the user data service.
$this->userData = $this->container
->get('user.data');
$random_value = $this
->randomName();
$this->userData
->set('views_test_config', $this->users[0]
->id(), 'test_value_name', $random_value);
$view = views_get_view('test_user_data');
$this
->executeView($view);
$output = $view->field['data']
->render($view->result[0]);
$this
->assertEqual($output, $random_value, 'A valid user data got rendered.');
$view->field['data']->options['name'] = $this
->randomName();
$output = $view->field['data']
->render($view->result[0]);
$this
->assertFalse($output, 'An invalid configuration does not return anything');
}