Allow users to provide route settings to `showMenu` (#124935)

Background: I am adding logging to things like dialogs, bottom sheets and menus. Then I realized that, showMenu does not allow users to provide RouteSettings, while showDialog and showModalBottomSheet both allow. Therefore, IMHO a consistent API design may need to add this to showMenu.

I will add tests if this proposal looks OK :)

packages/flutter/lib/src/material/popup_menu.dart

@@ -789,6 +789,7 @@ class _PopupMenuRoute<T> extends PopupRoute<T> {
     required this.capturedThemes,
     this.constraints,
     required this.clipBehavior,
+    super.settings,
   }) : itemSizes = List<Size?>.filled(items.length, null),
        // Menus always cycle focus through their items irrespective of the
        // focus traversal edge behavior set in the Navigator.
@@ -949,6 +950,7 @@ Future<T?> showMenu<T>({
   bool useRootNavigator = false,
   BoxConstraints? constraints,
   Clip clipBehavior = Clip.none,
+  RouteSettings? routeSettings,
 }) {
   assert(items.isNotEmpty);
   assert(debugCheckHasMaterialLocalizations(context));
@@ -979,6 +981,7 @@ Future<T?> showMenu<T>({
     capturedThemes: InheritedTheme.capture(from: context, to: navigator.context),
     constraints: constraints,
     clipBehavior: clipBehavior,
+    settings: routeSettings,
   ));
 }
 

packages/flutter/test/material/popup_menu_test.dart

@@ -3180,6 +3180,48 @@ void main() {
       paints..rrect(color: const Color(0xff0000ff)),
     );
   }, variant: TargetPlatformVariant.desktop());
+
+  testWidgets('Popup menu with RouteSettings', (WidgetTester tester) async {
+    late RouteSettings currentRouteSetting;
+
+    await tester.pumpWidget(
+      MaterialApp(
+        navigatorObservers: <NavigatorObserver>[
+          _ClosureNavigatorObserver(onDidChange: (Route<dynamic> newRoute) {
+            currentRouteSetting = newRoute.settings;
+          }),
+        ],
+        home: const Material(
+          child: Center(
+            child: ElevatedButton(
+              onPressed: null,
+              child: Text('Go'),
+            ),
+          ),
+        ),
+      ),
+    );
+
+    final BuildContext context = tester.element(find.text('Go'));
+    const RouteSettings exampleSetting = RouteSettings(name: 'simple');
+
+    showMenu<void>(
+      context: context,
+      position: RelativeRect.fill,
+      items: const <PopupMenuItem<void>>[
+        PopupMenuItem<void>(child: Text('foo')),
+      ],
+      routeSettings: exampleSetting,
+    );
+
+    await tester.pumpAndSettle();
+    expect(find.text('foo'), findsOneWidget);
+    expect(currentRouteSetting, exampleSetting);
+
+    await tester.tap(find.text('foo'));
+    await tester.pumpAndSettle();
+    expect(currentRouteSetting.name, '/');
+  });
 }
 
 class TestApp extends StatelessWidget {
@@ -3232,3 +3274,21 @@ class MenuObserver extends NavigatorObserver {
     super.didPush(route, previousRoute);
   }
 }
+
+class _ClosureNavigatorObserver extends NavigatorObserver {
+  _ClosureNavigatorObserver({required this.onDidChange});
+
+  final void Function(Route<dynamic> newRoute) onDidChange;
+
+  @override
+  void didPush(Route<dynamic> route, Route<dynamic>? previousRoute) => onDidChange(route);
+
+  @override
+  void didPop(Route<dynamic> route, Route<dynamic>? previousRoute) => onDidChange(previousRoute!);
+
+  @override
+  void didRemove(Route<dynamic> route, Route<dynamic>? previousRoute) => onDidChange(previousRoute!);
+
+  @override
+  void didReplace({Route<dynamic>? newRoute, Route<dynamic>? oldRoute}) => onDidChange(newRoute!);
+}