test(mobile): cover authenticated age gate

Co-authored-by: Tom Brow <tomb@block.xyz>
Signed-off-by: Tom Brow <tomb@block.xyz>

mobile/test/features/age_gate/age_gate_app_test.dart

@@ -3,6 +3,7 @@ import 'dart:async';
 import 'package:buzz/app.dart';
 import 'package:buzz/features/age_gate/age_restriction_page.dart';
 import 'package:buzz/features/age_gate/age_signal_provider.dart';
+import 'package:buzz/features/home/home_page.dart';
 import 'package:buzz/shared/auth/auth.dart';
 import 'package:buzz/shared/theme/theme_provider.dart';
 import 'package:flutter/material.dart';
@@ -18,6 +19,26 @@ void main() {
         .setMockMethodCallHandler(ageSignalChannel, null);
   });
 
+  testWidgets('blocks authenticated app content', (tester) async {
+    SharedPreferences.setMockInitialValues({});
+    final prefs = await SharedPreferences.getInstance();
+
+    await tester.pumpWidget(
+      ProviderScope(
+        overrides: [
+          authProvider.overrideWith(() => _AuthenticatedAuthNotifier()),
+          ageSignalProvider.overrideWith(() => _BlockingAgeSignalNotifier()),
+          savedPrefsProvider.overrideWithValue(prefs),
+        ],
+        child: const App(),
+      ),
+    );
+    await tester.pump();
+
+    expect(find.byType(AgeRestrictionPage), findsOneWidget);
+    expect(find.byType(HomePage), findsNothing);
+  });
+
   testWidgets('requests after the first frame and gates pushed routes', (
     tester,
   ) async {
@@ -63,6 +84,18 @@ void main() {
   });
 }
 
+class _AuthenticatedAuthNotifier extends AuthNotifier {
+  @override
+  Future<AuthState> build() async {
+    return const AuthState(status: AuthStatus.authenticated);
+  }
+}
+
+class _BlockingAgeSignalNotifier extends AgeSignalNotifier {
+  @override
+  bool build() => true;
+}
+
 class _FakeAuthNotifier extends AuthNotifier {
   @override
   Future<AuthState> build() async {