[go_router] fix: PopScope not honored for initial Routes inside ShellRoutes

packages/go_router/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 14.6.2
+
+- Fixed `PopScope`, and `WillPopScop` was not handled properly in root Shell routes.
+
 ## 14.6.1
 
 - Fixed `PopScope`, and `WillPopScop` was not handled properly in the Root routes.
@@ -10,7 +14,6 @@
 
 - Adds preload support to StatefulShellRoute, configurable via `preload` parameter on StatefulShellBranch.
 
-
 ## 14.4.1
 
 - Adds `missing_code_block_language_in_doc_comment` lint.
@@ -29,7 +32,7 @@
 
 ## 14.2.8
 
-- Updated custom_stateful_shell_route example to better support swiping in TabView as well as demonstration of the use of PageView. 
+- Updated custom_stateful_shell_route example to better support swiping in TabView as well as demonstration of the use of PageView.
 
 ## 14.2.7
 

packages/go_router/lib/src/delegate.dart

@@ -55,24 +55,52 @@ class GoRouterDelegate extends RouterDelegate<RouteMatchList>
 
   @override
   Future<bool> popRoute() async {
-    final NavigatorState? state = _findCurrentNavigator();
-    if (state != null) {
-      final bool didPop = await state.maybePop(); // Call maybePop() directly
-      if (didPop) {
-        return true; // Return true if maybePop handled the pop
-      }
-    }
+    // Walk up the tree to gather the navigator states that are present.
+    final List<(NavigatorState, RouteBase)> navigatorStates =
+        <(NavigatorState, RouteBase)>[
+      (navigatorKey.currentState!, currentConfiguration.matches.first.route),
+    ];
 
-    // Fallback to onExit if maybePop did not handle the pop
-    final GoRoute lastRoute = currentConfiguration.last.route;
-    if (lastRoute.onExit != null && navigatorKey.currentContext != null) {
-      return !(await lastRoute.onExit!(
-        navigatorKey.currentContext!,
-        currentConfiguration.last
-            .buildState(_configuration, currentConfiguration),
-      ));
+    RouteMatchBase walker = currentConfiguration.matches.last;
+
+    while (walker is ShellRouteMatch) {
+      final NavigatorState potentialCandidate =
+          walker.navigatorKey.currentState!;
+
+      navigatorStates.add((potentialCandidate, walker.matches.last.route));
+
+      walker = walker.matches.last;
     }
 
+    // Now we have a list of all the navigator states that are present in the
+    // current matched path. We now go through them in reverse order to check
+    // if they have an onExit callback and call it. If it returns false, we
+    // return true to indicate that the route pop was handled.
+    // If it returns true we proceed by trying to pop the route from the respective
+    // navigator. If this is successful (or prevented by doNotPop) we return true.
+    // If this (child) navigator cannot be popped because it has only one entry
+    // we continue with the next (parent) navigator.
+    for (final (NavigatorState navigatorState, RouteBase route)
+        in navigatorStates.reversed) {
+      // If the route has an onExit callback, call it and return false if it
+      // returns false.
+      if (route is GoRoute &&
+          route.onExit != null &&
+          !await route.onExit!(
+              navigatorKey.currentContext!,
+              currentConfiguration.last
+                  .buildState(_configuration, currentConfiguration))) {
+        return true;
+      }
+
+      // Try to pop the navigator state.
+      final bool didPop = await navigatorState.maybePop();
+      if (didPop) {
+        return true;
+      }
+    }
+    // Even the final (root) navigator cannot be popped, return false to exit
+    // the app
     return false;
   }
 

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: 14.6.1
+version: 14.6.2
 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/pop_scope_test.dart

@@ -0,0 +1,73 @@
+// 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/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:go_router/go_router.dart';
+
+import 'test_helpers.dart';
+
+void main() {
+  testWidgets('back button respects PopScope', (WidgetTester tester) async {
+    final UniqueKey home = UniqueKey();
+
+    bool onPopCalled = false;
+
+    final List<GoRoute> routes = <GoRoute>[
+      GoRoute(
+        path: '/',
+        builder: (BuildContext context, GoRouterState state) => PopScope(
+          canPop: false,
+          onPopInvokedWithResult: (bool didPop, Object? result) {
+            onPopCalled = true;
+          },
+          child: DummyScreen(key: home),
+        ),
+      ),
+    ];
+
+    final GoRouter router = await createRouter(routes, tester);
+
+    expect(await router.routerDelegate.popRoute(), true);
+    await tester.pumpAndSettle();
+
+    expect(onPopCalled, isTrue);
+
+    expect(find.byKey(home), findsOneWidget);
+  });
+
+  testWidgets('back button is respects PopScope in ShellRoute',
+      (WidgetTester tester) async {
+    bool onPopCalled = false;
+
+    final UniqueKey home = UniqueKey();
+
+    final List<RouteBase> routes = <RouteBase>[
+      ShellRoute(
+        builder: (BuildContext contex, GoRouterState state, Widget child) =>
+            child,
+        routes: <RouteBase>[
+          GoRoute(
+            path: '/',
+            builder: (BuildContext context, GoRouterState state) => PopScope(
+              canPop: false,
+              onPopInvokedWithResult: (bool didPop, Object? result) {
+                onPopCalled = true;
+              },
+              child: DummyScreen(key: home),
+            ),
+          ),
+        ],
+      ),
+    ];
+
+    final GoRouter router = await createRouter(routes, tester);
+
+    expect(await router.routerDelegate.popRoute(), true);
+    await tester.pumpAndSettle();
+
+    expect(onPopCalled, isTrue);
+
+    expect(find.byKey(home), findsOneWidget);
+  });
+}