Gc\Document\Model::getDocumentType PHP Method

    public function getDocumentType()
    {
        if ($this->getData('document_type') === null) {
            $this->setData('document_type', DocumentType\Model::fromId($this->getDocumentTypeId()));
        }
        return $this->getData('document_type');
    }

 /**
  * Test
  *
  * @return void
  */
 public function testGetEmptyIcon()
 {
     $this->object->getDocumentType()->setIconId(42000);
     $this->assertFalse($this->object->getIcon());
 }