[go_router] improve coverage (#977)

packages/go_router/CHANGELOG.md

@@ -1,7 +1,9 @@
-## NEXT
+## 3.0.5
 
 - Add `dispatchNotification` method to `DummyBuildContext` in tests. (This
   should be revisited when Flutter `2.11.0` becomes stable.)
+- Improves code coverage.
+- `GoRoute` now warns about requiring either `pageBuilder`, `builder` or `redirect` at instantiation.
 
 ## 3.0.4
 

packages/go_router/lib/src/go_route.dart

@@ -18,9 +18,9 @@ class GoRoute {
     required this.path,
     this.name,
     this.pageBuilder,
-    this.builder = _builder,
+    this.builder = _invalidBuilder,
     this.routes = const <GoRoute>[],
-    this.redirect = _redirect,
+    this.redirect = _noRedirection,
   }) {
     if (path.isEmpty) {
       throw Exception('GoRoute path cannot be empty');
@@ -30,6 +30,15 @@ class GoRoute {
       throw Exception('GoRoute name cannot be empty');
     }
 
+    if (pageBuilder == null &&
+        builder == _invalidBuilder &&
+        redirect == _noRedirection) {
+      throw Exception(
+        'GoRoute builder parameter not set\n'
+        'See gorouter.dev/redirection#considerations for details',
+      );
+    }
+
     // cache the path regexp and parameters
     _pathRE = patternToRegExp(path, _pathParams);
 
@@ -199,11 +208,11 @@ class GoRoute {
   Map<String, String> extractPathParams(RegExpMatch match) =>
       extractPathParameters(_pathParams, match);
 
-  static String? _redirect(GoRouterState state) => null;
+  static String? _noRedirection(GoRouterState state) => null;
 
-  static Widget _builder(BuildContext context, GoRouterState state) =>
-      throw Exception(
-        'GoRoute builder parameter not set\n'
-        'See gorouter.dev/redirection#considerations for details',
-      );
+  static Widget _invalidBuilder(
+    BuildContext context,
+    GoRouterState state,
+  ) =>
+      const SizedBox.shrink();
 }

packages/go_router/lib/src/inherited_go_router.dart

@@ -25,9 +25,9 @@ class InheritedGoRouter extends InheritedWidget {
   /// Used by the Router architecture as part of the InheritedWidget.
   @override
   // ignore: prefer_expression_function_bodies
-  bool updateShouldNotify(covariant InheritedWidget oldWidget) {
+  bool updateShouldNotify(covariant InheritedGoRouter oldWidget) {
     // avoid rebuilding the widget tree if the router has not changed
-    return false;
+    return goRouter != oldWidget.goRouter;
   }
 
   @override

packages/go_router/pubspec.yaml

@@ -1,7 +1,7 @@
 name: go_router
 description: A declarative router for Flutter based on Navigation 2 supporting
   deep linking, data-driven routes and more
-version: 3.0.4
+version: 3.0.5
 repository: https://github.com/flutter/packages/tree/main/packages/go_router
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+go_router%22
 

packages/go_router/test/custom_transition_page_test.dart

@@ -0,0 +1,114 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:go_router/go_router.dart';
+
+void main() {
+  testWidgets('CustomTransitionPage builds its child using transitionsBuilder',
+      (WidgetTester tester) async {
+    const HomeScreen child = HomeScreen();
+    final CustomTransitionPage<void> transition = CustomTransitionPage<void>(
+      transitionsBuilder: expectAsync4((_, __, ___, Widget child) => child),
+      child: child,
+    );
+    final GoRouter router = GoRouter(
+      routes: <GoRoute>[
+        GoRoute(
+          path: '/',
+          pageBuilder: (_, __) => transition,
+        ),
+      ],
+    );
+    await tester.pumpWidget(
+      MaterialApp.router(
+        routeInformationParser: router.routeInformationParser,
+        routerDelegate: router.routerDelegate,
+        title: 'GoRouter Example',
+      ),
+    );
+    expect(find.byWidget(child), findsOneWidget);
+  });
+
+  testWidgets('NoTransitionPage does not apply any transition',
+      (WidgetTester tester) async {
+    final ValueNotifier<bool> showHomeValueNotifier =
+        ValueNotifier<bool>(false);
+    await tester.pumpWidget(
+      MaterialApp(
+        home: ValueListenableBuilder<bool>(
+          valueListenable: showHomeValueNotifier,
+          builder: (_, bool showHome, __) {
+            return Navigator(
+              pages: <Page<void>>[
+                const NoTransitionPage<void>(
+                  child: LoginScreen(),
+                ),
+                if (showHome)
+                  const NoTransitionPage<void>(
+                    child: HomeScreen(),
+                  ),
+              ],
+              onPopPage: (Route<dynamic> route, dynamic result) {
+                return route.didPop(result);
+              },
+            );
+          },
+        ),
+      ),
+    );
+
+    final Finder homeScreenFinder = find.byType(HomeScreen);
+
+    showHomeValueNotifier.value = true;
+    await tester.pump();
+    final Offset homeScreenPositionInTheMiddleOfAddition =
+        tester.getTopLeft(homeScreenFinder);
+    await tester.pumpAndSettle();
+    final Offset homeScreenPositionAfterAddition =
+        tester.getTopLeft(homeScreenFinder);
+
+    showHomeValueNotifier.value = false;
+    await tester.pump();
+    final Offset homeScreenPositionInTheMiddleOfRemoval =
+        tester.getTopLeft(homeScreenFinder);
+    await tester.pumpAndSettle();
+
+    expect(
+      homeScreenPositionInTheMiddleOfAddition,
+      homeScreenPositionAfterAddition,
+    );
+    expect(
+      homeScreenPositionAfterAddition,
+      homeScreenPositionInTheMiddleOfRemoval,
+    );
+  });
+}
+
+class HomeScreen extends StatelessWidget {
+  const HomeScreen({Key? key}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return const Scaffold(
+      body: Center(
+        child: Text('HomeScreen'),
+      ),
+    );
+  }
+}
+
+class LoginScreen extends StatelessWidget {
+  const LoginScreen({Key? key}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return const Scaffold(
+      body: Center(
+        child: Text('LoginScreen'),
+      ),
+    );
+  }
+}

packages/go_router/test/error_screen_helpers.dart

@@ -0,0 +1,66 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:go_router/go_router.dart';
+
+import 'go_router_test.dart';
+
+WidgetTesterCallback testPageNotFound({required Widget widget}) {
+  return (WidgetTester tester) async {
+    await tester.pumpWidget(widget);
+    expect(find.text('page not found'), findsOneWidget);
+  };
+}
+
+WidgetTesterCallback testPageShowsExceptionMessage({
+  required Exception exception,
+  required Widget widget,
+}) {
+  return (WidgetTester tester) async {
+    await tester.pumpWidget(widget);
+    expect(find.text('$exception'), findsOneWidget);
+  };
+}
+
+WidgetTesterCallback testClickingTheButtonRedirectsToRoot({
+  required Finder buttonFinder,
+  required Widget widget,
+  Widget Function(GoRouter router) appRouterBuilder = materialAppRouterBuilder,
+}) {
+  return (WidgetTester tester) async {
+    final GoRouter router = GoRouter(
+      initialLocation: '/error',
+      routes: <GoRoute>[
+        GoRoute(path: '/', builder: (_, __) => const DummyStatefulWidget()),
+        GoRoute(
+          path: '/error',
+          builder: (_, __) => widget,
+        ),
+      ],
+    );
+    await tester.pumpWidget(appRouterBuilder(router));
+    await tester.tap(buttonFinder);
+    await tester.pumpAndSettle();
+    expect(find.byType(DummyStatefulWidget), findsOneWidget);
+  };
+}
+
+Widget materialAppRouterBuilder(GoRouter router) {
+  return MaterialApp.router(
+    routeInformationParser: router.routeInformationParser,
+    routerDelegate: router.routerDelegate,
+    title: 'GoRouter Example',
+  );
+}
+
+Widget cupertinoAppRouterBuilder(GoRouter router) {
+  return CupertinoApp.router(
+    routeInformationParser: router.routeInformationParser,
+    routerDelegate: router.routerDelegate,
+    title: 'GoRouter Example',
+  );
+}

packages/go_router/test/go_route_test.dart

@@ -0,0 +1,12 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:go_router/go_router.dart';
+
+void main() {
+  test('throws when a builder is not set', () {
+    expect(() => GoRoute(path: '/'), throwsException);
+  });
+}

packages/go_router/test/go_router_cupertino_test.dart

@@ -0,0 +1,105 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:go_router/src/go_router_cupertino.dart';
+
+import 'error_screen_helpers.dart';
+
+void main() {
+  group('isCupertinoApp', () {
+    testWidgets('returns [true] when CupertinoApp is present',
+        (WidgetTester tester) async {
+      final GlobalKey<_DummyStatefulWidgetState> key =
+          GlobalKey<_DummyStatefulWidgetState>();
+      await tester.pumpWidget(
+        CupertinoApp(
+          home: DummyStatefulWidget(key: key),
+        ),
+      );
+      final bool isCupertino = isCupertinoApp(key.currentContext! as Element);
+      expect(isCupertino, true);
+    });
+
+    testWidgets('returns [false] when MaterialApp is present',
+        (WidgetTester tester) async {
+      final GlobalKey<_DummyStatefulWidgetState> key =
+          GlobalKey<_DummyStatefulWidgetState>();
+      await tester.pumpWidget(
+        MaterialApp(
+          home: DummyStatefulWidget(key: key),
+        ),
+      );
+      final bool isCupertino = isCupertinoApp(key.currentContext! as Element);
+      expect(isCupertino, false);
+    });
+  });
+
+  test('pageBuilderForCupertinoApp creates a [CupertinoPage] accordingly', () {
+    final UniqueKey key = UniqueKey();
+    const String name = 'name';
+    const String arguments = 'arguments';
+    const String restorationId = 'restorationId';
+    const DummyStatefulWidget child = DummyStatefulWidget();
+    final CupertinoPage<void> page = pageBuilderForCupertinoApp(
+      key: key,
+      name: name,
+      arguments: arguments,
+      restorationId: restorationId,
+      child: child,
+    );
+    expect(page.key, key);
+    expect(page.name, name);
+    expect(page.arguments, arguments);
+    expect(page.restorationId, restorationId);
+    expect(page.child, child);
+  });
+
+  group('GoRouterCupertinoErrorScreen', () {
+    testWidgets(
+      'shows "page not found" by default',
+      testPageNotFound(
+        widget: const CupertinoApp(
+          home: GoRouterCupertinoErrorScreen(null),
+        ),
+      ),
+    );
+
+    final Exception exception = Exception('Something went wrong!');
+    testWidgets(
+      'shows the exception message when provided',
+      testPageShowsExceptionMessage(
+        exception: exception,
+        widget: CupertinoApp(
+          home: GoRouterCupertinoErrorScreen(exception),
+        ),
+      ),
+    );
+
+    testWidgets(
+      'clicking the CupertinoButton should redirect to /',
+      testClickingTheButtonRedirectsToRoot(
+        buttonFinder: find.byType(CupertinoButton),
+        appRouterBuilder: cupertinoAppRouterBuilder,
+        widget: const CupertinoApp(
+          home: GoRouterCupertinoErrorScreen(null),
+        ),
+      ),
+    );
+  });
+}
+
+class DummyStatefulWidget extends StatefulWidget {
+  const DummyStatefulWidget({Key? key}) : super(key: key);
+
+  @override
+  State<DummyStatefulWidget> createState() => _DummyStatefulWidgetState();
+}
+
+class _DummyStatefulWidgetState extends State<DummyStatefulWidget> {
+  @override
+  Widget build(BuildContext context) => Container();
+}