SortableGroup error testcase

tests/Gedmo/Sortable/Fixture/Transport/Vehicle.php

@@ -7,7 +7,7 @@ use Doctrine\ORM\Mapping as ORM;
 
 /**
  * @ORM\Entity
- * @ORM\InheritanceType("SINGLE_TABLE")
+ * @ORM\InheritanceType("JOINED")
  * @ORM\DiscriminatorColumn(name="discriminator", type="string")
  * @ORM\DiscriminatorMap({
  *      "vehicle" = "Vehicle",

tests/Gedmo/Sortable/SortableGroupTest.php

@@ -57,8 +57,9 @@ class SortableGroupTest extends BaseTestCaseORM
 
         $icarus = $this->em->getRepository(self::BUS)->findOneByTitle('Icarus');
         $this->assertEquals(2, $icarus->getSortByEngine());
-        //$this->em->remove($audi);
-        //$this->em->flush();
+
+        $this->em->remove($audi80);
+        $this->em->flush();
     }
 
     protected function getUsedEntityFixtures()