anchor.diff:                      Err = enacl:box_open([<<"x">>, CipherText], Nonce, PK1, SK2),
                       equals(Err, {error, failed_verification});
                   false ->
  -                    case box(iolist_to_binary(Msg), Nonce, PK2, SK1) of
  +                    case box(Msg, Nonce, PK2, SK1) of
                         badarg -> true;
                         Res ->
                           failure(box_open(Res, Nonce, PK1, SK2))
  
positive.code: 
  prop_stream_xor_correct() ->
      ?FORALL({Msg, Nonce, Key},
              {g_iodata(),
               fault_rate(1, 40, nonce()),
               fault_rate(1, 40, secret_key())},
          case v_iodata(Msg) andalso nonce_valid(Nonce) andalso secret_key_valid(Key) of
  
negative.code: 
  prop_auth_verify_correct() ->
      ?FORALL({Msg, Key},
              {fault_rate(1, 40, g_iodata()),
               fault_rate(1, 40, secret_key())},
        ?FORALL(Authenticator, authenticator(Msg, Key),
          case v_iodata(Msg) andalso secret_key_valid(Key) andalso authenticator_valid(Authenticator) of
  