business\DateTimeStorage::getHash PHP Method

    public function getHash($object)
    {
        return $object->format('Y-m-d');
    }

 public function testHash()
 {
     $dateTimeStorage = new DateTimeStorage();
     $dateTime = new \DateTime('2015-07-08');
     $this->assertEquals('2015-07-08', $dateTimeStorage->getHash($dateTime));
 }