anchor.diff:          'adds BonusLetterActivated to GameBloc when not activated',
           (game, tester) async {
             await game.ready();
  -
  -          _getBonusLetter(game).activate();
  +          final bonusLetter = game.descendants().whereType<BonusLetter>().first;
  +          bonusLetter.activate();
  +          await game.ready();
   
             await tester.pump();
  -
             verify(() => gameBloc.add(const BonusLetterActivated(0))).called(1);
           },
         );
  
positive.code:             bonusHistory: [],
            );
  
            final bonusLetter = _getBonusLetter(game);
  
            bonusLetter.onNewState(state);
            await tester.pump();
  
negative.code:       tester.widgetTest(
          'adds a ColorEffect',
          (game, tester) async {
            const state = GameState(
              score: 0,
              balls: 2,
  