public function testGetXml()
 {
     $config = $this->getTestConfig();
     $params = $this->getPurchaseParams();
     $purchaseTransaction = new Purchase($config, $params);
     $xml = $purchaseTransaction->getXml();
     $this->assertTrue(isset($xml->purchase));
     $this->assertEquals($config->getCryptType(), (string) $xml->purchase->crypt_type);
     $this->assertEquals($params['order_id'], (string) $xml->purchase->order_id);
     $this->assertEquals($params['amount'], (string) $xml->purchase->amount);
     $this->assertEquals($params['cc_number'], (string) $xml->purchase->pan);
 }