public function testRestoreVersion()
 {
     $user = $this->dm->find($this->typeVersion, '/functional/versionTestObj');
     $this->dm->checkpoint($user);
     $user->username = '******';
     $this->dm->flush();
     $versions = $this->dm->getAllLinearVersions($user);
     each($versions);
     list($dummy, $versionInfo) = each($versions);
     $versionName = $versionInfo['name'];
     $versionDocument = $this->dm->findVersionByName($this->typeVersion, '/functional/versionTestObj', $versionName);
     $this->dm->restoreVersion($versionDocument);
     $this->assertEquals('lsmith', $user->username);
     $this->dm->clear();
     $user = $this->dm->find($this->typeVersion, '/functional/versionTestObj');
     $this->assertEquals('lsmith', $user->username);
 }