public function assertSqlGeneration($dqlToBeTested, $sqlToBeConfirmed)
 {
     try {
         $query = $this->_em->createQuery($dqlToBeTested);
         $query->setHint(Query::HINT_CUSTOM_TREE_WALKERS, array('Doctrine\\Tests\\ORM\\Functional\\CustomTreeWalker'))->useQueryCache(false);
         parent::assertEquals($sqlToBeConfirmed, $query->getSql());
         $query->free();
     } catch (\Exception $e) {
         $this->fail($e->getMessage());
     }
 }