/**
  * Use MCRYPT backing
  */
 public function setUp()
 {
     SecureString::useBacking(SecureString::BACKING_MCRYPT);
 }
 /**
  * Use OPENSSL backing
  */
 public function setUp()
 {
     SecureString::useBacking(SecureString::BACKING_OPENSSL);
 }
 public function useBacking_with_invalid_backing_throws_exception()
 {
     SecureString::useBacking(77);
 }
 /**
  * Use PLAINTEXT backing
  */
 public function setUp()
 {
     SecureString::useBacking(SecureString::BACKING_PLAINTEXT);
 }