anchor.diff:    }
   }
   
  +Uint8List _coerceUint8List(List<int> list) =>
  +    list is Uint8List ? list : new Uint8List.fromList(list);
  +
   class ScramSha1Mechanism extends SaslMechanism {
     final UsernamePasswordCredential credential;
     final RandomStringGenerator randomStringGenerator;
  
positive.code:     var clientFirstMessageBare = '$username,$nonce';
      var clientFirstMessage = '$gs2Header$clientFirstMessageBare';
  
      return new ClientFirst(
          utf8.encode(clientFirstMessage), credential, clientFirstMessageBare, r);
    }
  
    String prepUsername(String username) =>
  
negative.code:     var proof = 'p=$base64clientProof';
      var clientFinalMessage = '$clientFinalMessageWithoutProof,$proof';
  
      return new ClientLast(
          _coerceUint8List(utf8.encode(clientFinalMessage)), serverSignature);
    }
  
    static Uint8List computeHMAC(Uint8List data, String key) {
  