anchor.diff:  
     @override
     int compare(ClassHeapDetailStats a, ClassHeapDetailStats b) {
  -    final Comparable valueA = getValue(a);
  -    final Comparable valueB = getValue(b);
  +    final Comparable valueA = getValue(a)!;
  +    final Comparable valueB = getValue(b)!;
       return valueA.compareTo(valueB);
     }
   }
  
positive.code:   FieldClassName() : super('Class', fixedWidthPx: scaleByFontFactor(200.0));
  
    @override
    String getValue(ClassHeapDetailStats dataObject) => dataObject.classRef.name;
  
    @override
    String getDisplayValue(ClassHeapDetailStats dataObject) =>
  
negative.code:     BuildContext context,
      ClassHeapDetailStats item, {
      bool isRowSelected = false,
      VoidCallback? onPressed,
    }) {
      final controller = Provider.of<MemoryController>(context);
  
      return Checkbox(
        value: item.isStacktraced,
        onChanged: (value) {
          controller.toggleAllocationTracking(item, value!);
        },
      );
    }
  