Doctrine\ODM\MongoDB\DocumentManager::getDocumentDatabases PHP Method

    public function getDocumentDatabases()
    {
        return $this->documentDatabases;
    }

 /**
  * {@inheritdoc}
  */
 protected function tearDown()
 {
     if ($this->dm) {
         foreach ($this->dm->getDocumentDatabases() as $db) {
             foreach ($db->listCollections() as $collection) {
                 $collection->drop();
             }
         }
         $this->dm->getConnection()->close();
         $this->dm = null;
     }
 }