[go_router_builder] Add test for onExit (#6614)

Follows #6495
Fixes flutter/flutter#137394

Author: ValentinVignal

packages/go_router_builder/CHANGELOG.md

@@ -1,6 +1,7 @@
-## NEXT
+## 2.7.0
 
-* Updates minimum supported SDK version to Flutter 3.16/Dart 3.2.
+- Adds an example and a test with `onExit`.
+- Updates minimum supported SDK version to Flutter 3.16/Dart 3.2.
 
 ## 2.6.2
 

packages/go_router_builder/example/lib/on_exit_example.dart

@@ -0,0 +1,96 @@
+// 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.
+
+// ignore_for_file: public_member_api_docs, unreachable_from_main
+
+import 'package:flutter/material.dart';
+import 'package:go_router/go_router.dart';
+
+part 'on_exit_example.g.dart';
+
+void main() => runApp(App());
+
+class App extends StatelessWidget {
+  App({super.key});
+
+  @override
+  Widget build(BuildContext context) => MaterialApp.router(
+        routerConfig: _router,
+        title: _appTitle,
+      );
+
+  final GoRouter _router = GoRouter(routes: $appRoutes);
+}
+
+@TypedGoRoute<HomeRoute>(
+  path: '/',
+  routes: <TypedGoRoute<GoRouteData>>[
+    TypedGoRoute<SubRoute>(path: 'sub-route')
+  ],
+)
+class HomeRoute extends GoRouteData {
+  const HomeRoute();
+
+  @override
+  Widget build(BuildContext context, GoRouterState state) => const HomeScreen();
+}
+
+class SubRoute extends GoRouteData {
+  const SubRoute();
+
+  @override
+  Future<bool> onExit(BuildContext context, GoRouterState state) async {
+    final bool? confirmed = await showDialog<bool>(
+      context: context,
+      builder: (_) => AlertDialog(
+        content: const Text('Are you sure to leave this page?'),
+        actions: <Widget>[
+          TextButton(
+            onPressed: () => Navigator.of(context).pop(false),
+            child: const Text('Cancel'),
+          ),
+          ElevatedButton(
+            onPressed: () => Navigator.of(context).pop(true),
+            child: const Text('Confirm'),
+          ),
+        ],
+      ),
+    );
+    return confirmed ?? false;
+  }
+
+  @override
+  Widget build(BuildContext context, GoRouterState state) => const SubScreen();
+}
+
+class HomeScreen extends StatelessWidget {
+  const HomeScreen({super.key});
+
+  @override
+  Widget build(BuildContext context) => Scaffold(
+      appBar: AppBar(title: const Text(_appTitle)),
+      body: Center(
+        child: ElevatedButton(
+          onPressed: () => const SubRoute().go(context),
+          child: const Text('Go to sub screen'),
+        ),
+      ));
+}
+
+class SubScreen extends StatelessWidget {
+  const SubScreen({super.key});
+
+  @override
+  Widget build(BuildContext context) => Scaffold(
+        appBar: AppBar(title: const Text('$_appTitle Sub screen')),
+        body: Center(
+          child: ElevatedButton(
+            onPressed: () => Navigator.of(context).pop(),
+            child: const Text('Go back'),
+          ),
+        ),
+      );
+}
+
+const String _appTitle = 'GoRouter Example: builder';

packages/go_router_builder/example/lib/on_exit_example.g.dart

@@ -9,7 +9,7 @@ dependencies:
   collection: ^1.15.0
   flutter:
     sdk: flutter
-  go_router: ^10.0.0
+  go_router: ^14.1.1
   provider: 6.0.5
 
 dev_dependencies:

packages/go_router_builder/example/pubspec.yaml

@@ -0,0 +1,46 @@
+// 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_builder_example/on_exit_example.dart';
+
+void main() {
+  testWidgets('It should trigger the on exit when leaving the route',
+      (WidgetTester tester) async {
+    await tester.pumpWidget(App());
+    expect(find.byType(HomeScreen), findsOne);
+
+    await tester.tap(find.widgetWithText(ElevatedButton, 'Go to sub screen'));
+    await tester.pumpAndSettle();
+
+    expect(find.byType(SubScreen), findsOne);
+
+    await tester.tap(find.widgetWithText(ElevatedButton, 'Go back'));
+    await tester.pumpAndSettle();
+
+    expect(
+      find.widgetWithText(AlertDialog, 'Are you sure to leave this page?'),
+      findsOne,
+    );
+    await tester.tap(find.text('Cancel'));
+    await tester.pumpAndSettle();
+
+    expect(find.byType(HomeScreen), findsNothing);
+    expect(find.byType(SubScreen), findsOne);
+
+    await tester.tap(find.widgetWithText(ElevatedButton, 'Go back'));
+    await tester.pumpAndSettle();
+
+    expect(
+      find.widgetWithText(AlertDialog, 'Are you sure to leave this page?'),
+      findsOne,
+    );
+    await tester.tap(find.text('Confirm'));
+    await tester.pumpAndSettle();
+
+    expect(find.byType(HomeScreen), findsOne);
+    expect(find.byType(SubScreen), findsNothing);
+  });
+}

packages/go_router_builder/example/test/on_exit_example_test.dart

@@ -2,7 +2,7 @@ name: go_router_builder
 description: >-
   A builder that supports generated strongly-typed route helpers for
   package:go_router
-version: 2.6.2
+version: 2.7.0
 repository: https://github.com/flutter/packages/tree/main/packages/go_router_builder
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+go_router_builder%22
 
@@ -26,7 +26,7 @@ dev_dependencies:
   dart_style: 2.3.6
   flutter:
     sdk: flutter
-  go_router: ^10.0.0
+  go_router: ^14.0.0
   test: ^1.20.0
 
 topics: