Fix no rebuild when listening to context of Selector.builder (#863)

Fixes #339

packages/provider/lib/src/selector.dart

@@ -82,10 +82,12 @@ class _Selector0State<T> extends SingleChildState<Selector0<T>> {
  if (shouldInvalidateCache) {
  value = selected;
  oldWidget = widget;
- cache = widget.builder(
- context,
- selected,
- child,
+ cache = Builder(
+ builder: (context) => widget.builder(
+ context,
+ selected,
+ child,
+ ),
  );
  }
  return cache!;

packages/provider/test/null_safe/selector_test.dart

@@ -334,6 +334,36 @@ void main() {
  expect(find.text('24'), findsOneWidget);
  });
 
+ testWidgets('rebuild when inherited widget changes', (tester) async {
+ final selectorWidget = Directionality(
+ textDirection: TextDirection.ltr,
+ child: Selector0<int>(
+ selector: (_) => 0,
+ builder: (context, _, __) =>
+ Text('${DummyInheritedWidget.of(context).data}'),
+ ),
+ );
+
+ await tester.pumpWidget(
+ DummyInheritedWidget(
+ data: 1,
+ child: selectorWidget,
+ ),
+ );
+
+ expect(find.text('1'), findsOneWidget);
+
+ await tester.pumpWidget(
+ DummyInheritedWidget(
+ data: 2,
+ child: selectorWidget,
+ ),
+ );
+
+ expect(find.text('1'), findsNothing);
+ expect(find.text('2'), findsOneWidget);
+ });
+
  testWidgets('debugFillProperties', (tester) async {
  final builder = DiagnosticPropertiesBuilder();
  final key = UniqueKey();
@@ -524,3 +554,23 @@ class MockBuilder<T> extends Mock {
  ) as Widget;
  }
 }
+
+class DummyInheritedWidget extends InheritedWidget {
+ const DummyInheritedWidget({
+ required this.data,
+ required Widget child,
+ Key? key,
+ }) : super(child: child, key: key);
+
+ final int data;
+
+ static DummyInheritedWidget of(BuildContext context) {
+ final result =
+ context.dependOnInheritedWidgetOfExactType<DummyInheritedWidget>();
+ assert(result != null, 'No DummyInheritedWidget found in context');
+ return result!;
+ }
+
+ @override
+ bool updateShouldNotify(DummyInheritedWidget old) => old.data != data;
+}