public function test_unsetData()
 {
     /* unset root */
     $obj = new DataObject('data');
     $this->assertEquals('data', $obj->getData());
     $obj->unsetData();
     $this->assertNull($obj->getData());
     /* unset key in root array */
     $obj->setKey('dataKey');
     $obj->setOther('dataOther');
     $this->assertEquals('dataKey', $obj->getKey());
     $obj->unsetKey();
     $this->assertNull($obj->getKey());
     $this->assertEquals('dataOther', $obj->getOther());
     /* unset by path */
     $obj->setData('Other/Node', 'dataNode');
     $this->assertEquals('dataNode', $obj->getData('/Other/Node'));
     $obj->unsetData('/Other/Node');
     /* wrong path */
     $obj->unsetData('/Other/WrongNode');
 }