The SliverMainAxisGroup.cacheOrigin is not consistent with CustomScrollView #175759
Description
Steps to reproduce
Add the test from code sample in file sliver_main_axis_group_test.dart of Flutter project.
Launch the test with SliverMainAxisGroup and launch with unwrapping SliverMainAxisGroup. The cacheOrgin values are different.
In one of our mobile application, we have inconsistent behavior on cached sliver widget when scrolling with and without SliverMainAxisGroup.
Expected results
The constraints.cacheOrigin of SliverList should be the same with or without SliverMainAxisGroup : -250.0
Actual results
The actual cacheOrigin is 0.
Code sample
testWidgets('SliverMainAxisGroup has consistent cacheOrigin', (WidgetTester tester) async {
const Widget item = SizedBox.square(dimension: 50);
await tester.pumpWidget(
MaterialApp(
home: CustomScrollView(
slivers: <Widget>[
SliverMainAxisGroup(
slivers: <Widget>[
const PinnedHeaderSliver(child: SizedBox(height: 500)),
SliverList.builder(
itemCount: 100,
itemBuilder: (BuildContext context, int index) => item,
),
const SliverToBoxAdapter(child: item),
],
),
],
),
),
);
await tester.scrollUntilVisible(find.byType(SliverToBoxAdapter), 500);
await tester.pumpAndSettle();
final RenderSliver sliverList =
find.byType(SliverList).evaluate().single.findRenderObject()! as RenderSliver;
expect(sliverList.constraints.cacheOrigin, -250.0);
expect(sliverList.constraints.remainingCacheExtent, 1100);
});Screenshots or Video
No response
Logs
No error visible.
Flutter Doctor output
Doctor output
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