anchor.diff:                const SizedBox(height: defaultSpacing),
               ],
               if (widget.toggleFilters != null)
  -              for (final toggleFilter in widget.toggleFilters) ...[
  +              for (final toggleFilter in widget.toggleFilters!) ...[
                   ToggleFilterElement(filter: toggleFilter),
                 ],
             ],
  
positive.code:     this.toggleFilters = const [],
    });
  
    final QueryFilter queryFilter;
  
    final List<ToggleFilter<T>> toggleFilters;
  }
  
  class ToggleFilter<T> {
    ToggleFilter({
      @required this.name,
      @required this.includeCallback,
      this.tooltip,
      this.enabledByDefault = false,
    }) : enabled = ValueNotifier<bool>(enabledByDefault);
  
negative.code: 
  class QueryFilterArgument {
    QueryFilterArgument({
      required this.keys,
      this.values = const [],
      this.isNegative = false,
    });
  