anchor.diff:    String get name => SCRAM;
   
     ScramSha1Authenticator(UsernamePasswordCredential credential, Db db)
  -      : super(new ScramSha1Mechanism(credential, new WeakRandomStringGenerator()),
  -      db) {
  +      : super(
  +            new ScramSha1Mechanism(credential, new WeakRandomStringGenerator()),
  +            db) {
       this.db = db;
     }
   }
  
positive.code:       return new Uint8List.fromList(hmac.close());
      };
  
      Uint8List newSalt = new Uint8List.fromList(new List.from(salt)..addAll([0,0,0,1]));
  
      var ui = digest(newSalt);
      var u1 = ui;
  
negative.code: 
    sb.write(s);
  
    for (int i = 0; i < paddingToAdd; ++i) {
      sb.write("=");
    }
  
    return sb.toString();
  }
  