/**
  * Make sure the the response has the given transaction details.
  *
  * @param array $details
  */
 public function hasTransactionDetails(array $details)
 {
     $default = ['reference' => null, 'id' => null, 'status' => null, 'payment_instructions' => null];
     $details = array_merge($default, $details);
     $this->assertSame($details['reference'], $this->response->getTransactionReference());
     $this->assertSame($details['id'], $this->response->getTransactionId());
     $this->assertSame($details['status'], $this->response->getTransactionStatus());
     $this->assertSame($details['payment_instructions'], $this->response->getPaymentInstructions());
 }