PHPUnit_Framework_Assert::assertInstanceOf PHP Method

    public static function assertInstanceOf($expected, $actual, $message = '')
    {
        if (!(is_string($expected) && (class_exists($expected) || interface_exists($expected)))) {
            throw PHPUnit_Util_InvalidArgumentHelper::factory(1, 'class or interface name');
        }
        $constraint = new PHPUnit_Framework_Constraint_IsInstanceOf($expected);
        static::assertThat($actual, $constraint, $message);
    }

 /**
  * @Given /^There are activity for questions$/
  */
 public function thereAreActivityForQuestions(TableNode $table)
 {
     /* @var $em EntityManager */
     $em = $this->getEm();
     /* @var $activityService \Civix\CoreBundle\Service\ActivityUpdate */
     $activityService = $this->getMainContext()->getContainer()->get('civix_core.activity_update');
     $hash = $table->getHash();
     $diffSec = 0;
     foreach ($hash as $row) {
         /* @var $question Question */
         $diffSec++;
         $question = $em->getRepository(Question::class)->findOneBySubject($row['question']);
         $activity = $activityService->publishQuestionToActivity($question);
         Assert::assertInstanceOf(Activity::class, $activity);
         $activity->getSentAt()->sub(new \DateInterval('PT' . (count($hash) - $diffSec) . 'S'));
         $activity->setSentAt(clone $activity->getSentAt());
         $em->flush($activity);
         if (!empty($row['expired_interval_direction'])) {
             $expired = new \DateTime();
             $expired->{$row}['expired_interval_direction'](new \DateInterval($row['expired_interval_value']));
             $activity->setExpireAt($expired);
             $em->flush($activity);
         }
     }
     $result = $em->getRepository(QuestionActivity::class)->findAll();
     Assert::assertTrue(count($result) >= count($hash));
 }