anchor.diff:  
       expect(getRenderSegmentedControl(tester).selectedIndex, null);
   
  -    final dynamic childList = getRenderSegmentedControl(tester).getChildrenAsList();
  +    final dynamic childList =
  +        getRenderSegmentedControl(tester).getChildrenAsList();
   
       expect(
         getRenderSegmentedControl(tester),
  
positive.code:   });
  
    testWidgets('Null input for value results in no child initially selected',
            (WidgetTester tester) async {
      final Map<int, Widget> children = <int, Widget>{};
      children[0] = const Text('Child 1');
      children[1] = const Text('Child 2');
  
negative.code:       ),
      );
  
      final dynamic childList =
          getRenderSegmentedControl(tester).getChildrenAsList();
  
      expect(
        getRenderSegmentedControl(tester),
  