anchor.diff:  void main() {
     // Common
     final cbor.ListenerDebug listener = new cbor.ListenerDebug();
  +  final cbor.ListenerStack slistener = new cbor.ListenerStack();
   
     group('Original C++ tests', () {
       test('Encode/Decode confidence -> ', () {
  
positive.code:       final cbor.Decoder decoder =
        new cbor.Decoder.withListener(input, listener);
        decoder.run();
      });
  
      test('Map -> ', () {
  
negative.code:       final cbor.Decoder decoder =
        new cbor.Decoder.withListener(input, listener);
        decoder.run();
        decoder.setListener(slistener);
        slistener.stack.clear();
        input.reset();
        decoder.run();
        final List<dynamic> slist = slistener.stack.walk();
        expect(slist.length, 1);
        expect(slist[0], {
          "half": 0.0,
          "single": 3.4028234663852886e+38,
          "simple values": [true, false, null]
        });
      });
  
      test('Indefinitite string -> ', () {
  