Omnipay\PayPal\RestGateway::fetchTransaction PHP Method

    public function fetchTransaction(array $parameters = array())
    {
        return $this->createRequest('\\Omnipay\\PayPal\\Message\\RestFetchTransactionRequest', $parameters);
    }

 public function testFetchTransaction()
 {
     $request = $this->gateway->fetchTransaction(array('transactionReference' => 'abc123'));
     $this->assertInstanceOf('\\Omnipay\\PayPal\\Message\\RestFetchTransactionRequest', $request);
     $this->assertSame('abc123', $request->getTransactionReference());
     $data = $request->getData();
     $this->assertEmpty($data);
 }