public function testCompleteSubscription()
{
$this->setMockHttpResponse('RestExecuteSubscriptionSuccess.txt');
$response = $this->gateway->completeSubscription($this->subscription_options)->send();
$this->assertTrue($response->isSuccessful());
$this->assertNull($response->getMessage());
$this->assertEquals('I-0LN988D3JACS', $response->getTransactionReference());
}