anchor.diff:    }
   
     Widget build() {
  -    return game.generateUI();
  +    return game.buildUI();
     }
   }
   
  
positive.code:     }
    }
  
    Widget generateBoard() {
      bool hasCoveredCell = false;
      List<Flex> flexRows = new List<Flex>();
      for (int iy = 0; iy != 9; iy++) {
  
negative.code: 
  import 'package:sky/rendering/flex.dart';
  import 'package:sky/widgets/basic.dart';
  import 'package:sky/widgets/scaffold.dart';
  import 'package:sky/widgets/tool_bar.dart';
  import 'package:sky/widgets/theme.dart';
  import 'package:sky/theme/colors.dart' as colors;
  import 'package:sky/painting/text_style.dart';
  
  // Classic minesweeper-inspired game. The mouse controls are standard except
  // for left + right combo which is not implemented. For touch, the duration of
  // the pointer determines probing versus flagging.
  //
  // There are only 3 classes to understand. Game, which is contains all the
  // logic and two UI classes: CoveredMineNode and ExposedMineNode, none of them
  // holding state.
  
  