Add root rebuild test

lib/src/pages/page_stack.dart

@@ -69,10 +69,7 @@ class PageStack extends ChangeNotifier {
 
   Iterable<PageWrapper> _getCurrentPages() sync* {
     if (_pageWrappers.isNotEmpty) {
-      for (final wrapper in _pageWrappers) {
-        yield wrapper;
-      }
-
+      yield* _pageWrappers;
       yield* _pageWrappers.last.getCurrentPages();
     }
   }

test/helpers.dart

@@ -7,6 +7,13 @@ import 'package:routemaster/src/system_nav.dart';
 
 const kTransitionDuration = Duration(milliseconds: 310);
 
+extension PumpExtension on WidgetTester {
+  Future<void> pumpPageTransition() async {
+    await pump();
+    await pump(kTransitionDuration);
+  }
+}
+
 class MockHistoryProvider implements HistoryProvider {
   final void Function(String) onReplaceState;
 

test/root_tab_rebuild_test.dart

@@ -0,0 +1,148 @@
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:routemaster/routemaster.dart';
+import 'helpers.dart';
+
+void main() {
+  testWidgets("Doesn't rebuild root tab page when page pushed on top",
+      (tester) async {
+    final delegate = RoutemasterDelegate(
+      routesBuilder: (BuildContext context) {
+        return RouteMap(
+          routes: {
+            '/': (_) => const Redirect('/home/1'),
+            '/home/:homeId': (_) {
+              return TabPage(
+                child: HomePage(),
+                paths: const ['one', 'two'],
+              );
+            },
+            '/home/:homeId/one': (_) => const MaterialPageOne(),
+            '/home/:homeId/two': (_) => const MaterialPageTwo(),
+            '/home/:homeId/two/edit': (_) => const MaterialPageThree(),
+            '/home/:homeId/eq/:eqId': (route) {
+              return MaterialPage<void>(
+                key: ValueKey(route.pathParameters['eqId']!),
+                child: const EchoPage(),
+              );
+            },
+          },
+        );
+      },
+    );
+
+    await tester.pumpWidget(MaterialApp.router(
+      routeInformationParser: const RoutemasterParser(),
+      routerDelegate: delegate,
+    ));
+
+    expect(find.byType(PageOne), findsOneWidget);
+    expect(find.byType(PageTwo), findsNothing);
+
+    // Switch to second tab
+    expect(
+      await recordUrlChanges(() async {
+        delegate.push('/home/1/two');
+        await tester.pumpPageTransition();
+
+        expect(find.byType(PageOne), findsNothing);
+        expect(find.byType(PageTwo), findsOneWidget);
+      }),
+      ['/home/1/two'],
+    );
+
+    // Push within tab view
+    expect(
+      await recordUrlChanges(() async {
+        delegate.push('/home/1/two/edit');
+        await tester.pumpPageTransition();
+        expect(find.byType(PageThree), findsOneWidget);
+      }),
+      ['/home/1/two/edit'],
+    );
+
+    // Push over tab view
+    expect(
+      await recordUrlChanges(() async {
+        delegate.push('/home/1/eq/1');
+        await tester.pumpPageTransition();
+        expect(find.byType(EchoPage), findsOneWidget);
+        expect(find.text('1'), findsOneWidget);
+      }),
+      ['/home/1/eq/1'],
+    );
+
+    // Replace pushed page with another
+    expect(
+      await recordUrlChanges(() async {
+        delegate.push('/home/1/eq/2');
+        await tester.pumpPageTransition();
+        expect(find.byType(EchoPage), findsOneWidget);
+        expect(find.text('2'), findsOneWidget);
+      }),
+      ['/home/1/eq/2'],
+    );
+
+    expect(
+      await recordUrlChanges(() async {
+        await delegate.pop();
+        await tester.pumpPageTransition();
+      }),
+      ['/home/1/two/edit'],
+    );
+
+    expect(
+      await recordUrlChanges(() async {
+        await delegate.pop();
+        await tester.pumpPageTransition();
+        expect(find.byType(HomePage), findsOneWidget);
+      }),
+      ['/home/1/two'],
+    );
+
+    expect(find.byType(PageOne), findsNothing);
+    expect(find.byType(PageTwo), findsOneWidget);
+  });
+}
+
+class HomePage extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    final tabState = TabPage.of(context);
+
+    return Scaffold(
+      body: TabBarView(
+        controller: tabState.controller,
+        children: [
+          for (final stack in tabState.stacks) PageStackNavigator(stack: stack)
+        ],
+      ),
+      bottomNavigationBar: BottomNavigationBar(
+        currentIndex: tabState.index,
+        onTap: (index) => tabState.controller.animateTo(index),
+        items: const [
+          BottomNavigationBarItem(
+            label: 'one',
+            icon: Icon(CupertinoIcons.add),
+          ),
+          BottomNavigationBarItem(
+            label: 'two',
+            icon: Icon(CupertinoIcons.building_2_fill),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+class EchoPage extends StatelessWidget {
+  const EchoPage({Key? key}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      body: Text(RouteData.of(context).pathParameters['eqId']!),
+    );
+  }
+}