anchor.diff:    });
   
     testWidgets('Horizontal fling does not trigger at zero offset, but does otherwise', (WidgetTester tester) async {
  -    scrollDirection = Axis.vertical;
  -    dismissDirection = DismissDirection.horizontal;
  -
  -    await tester.pumpWidget(buildTest(startToEndThreshold: 0.95));
  +    await tester.pumpWidget(
  +      buildTest(
  +        startToEndThreshold: 0.95,
  +        scrollDirection: Axis.vertical,
  +        dismissDirection: DismissDirection.horizontal,
  +      ),
  +    );
       expect(dismissedItems, isEmpty);
   
       await dismissItem(tester, 0, gestureDirection: AxisDirection.right, mechanism: flingElementFromZero);
  
positive.code:   });
  
    testWidgets('Dismissible starts from the full size when collapsing', (WidgetTester tester) async {
      scrollDirection = Axis.vertical;
      dismissDirection = DismissDirection.horizontal;
      background = const Text('background');
  
      await tester.pumpWidget(buildTest());
      expect(dismissedItems, isEmpty);
  
      final Finder itemFinder = find.text('0');
  
negative.code:   });
  
    testWidgets('drag-left with DismissDirection.endToStart triggers dismiss (LTR)', (WidgetTester tester) async {
      await tester.pumpWidget(
        buildTest(
          scrollDirection: Axis.vertical,
          dismissDirection: DismissDirection.endToStart,
        ),
      );
      expect(dismissedItems, isEmpty);
  
      await dismissItem(tester, 0, gestureDirection: AxisDirection.right);
  