public function testAProperAppSecretProofCanBeGenerated()
 {
     $response = new FacebookResponse($this->request);
     $appSecretProof = $response->getAppSecretProof();
     $this->assertEquals('df4256903ba4e23636cc142117aa632133d75c642bd2a68955be1443bd14deb9', $appSecretProof);
 }