Deep Linking Issue on iOS from "Not Launched" State

[kirya355]

I'm experiencing an issue with deep linking on iOS using auto_route. When the app is in the "not launched" state, deeplinks do not open correctly "/second" route, only "/" route.
However, if I reduce the delay in the Future.delayed during initialization to 1 second, everything works fine. The issue occurs when the delay is set to 3 seconds. Additionally, deep links work correctly when the app is already open or minimized.

Steps to Reproduce:

1. Set up a Flutter app with auto_route
   Code Example:

main.dart

import 'dart:async';

import 'package:auto_route/auto_route.dart';
import 'package:flutter/material.dart';

part 'main.gr.dart';

Future<void> main() async {
  final binding = WidgetsFlutterBinding.ensureInitialized();
  binding.deferFirstFrame();

  try {
    //? Simulating initialization
    await Future.delayed(const Duration(seconds: 3));

    runApp(const MyApp());
  } catch (e) {
    runApp(MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Error'),
        ),
      ),
    ));
  } finally {
    if (!binding.sendFramesToEngine) {
      binding.allowFirstFrame();
    }
  }
}

@AutoRouterConfig()
class AppRouter extends RootStackRouter {
  static GlobalKey<ScaffoldMessengerState> get getRootScaffoldMessengerKey =>
      _rootScaffoldMessengerKey;

  static final GlobalKey<ScaffoldMessengerState> _rootScaffoldMessengerKey =
      GlobalKey<ScaffoldMessengerState>();

  @override
  List<AutoRoute> get routes => [
        AutoRoute(
          path: '/',
          page: MyHomeRoute.page,
        ),
        AutoRoute(
          path: '/second',
          page: MySecondRoute.page,
        ),
        RedirectRoute(
          path: '*',
          redirectTo: '/',
        ),
      ];
}

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  final _router = AppRouter();

  void showMessage(String text) {
    final ScaffoldMessengerState? s = AppRouter.getRootScaffoldMessengerKey.currentState;
    s?.showSnackBar(SnackBar(content: Text(text)));
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp.router(
      scaffoldMessengerKey: AppRouter.getRootScaffoldMessengerKey,
      title: 'Flutter Demo',
      routerConfig: _router.config(
        deepLinkBuilder: (deepLink) async {
          final uri = deepLink.uri;
          final initial = deepLink.initial;

          unawaited(Future.delayed(const Duration(seconds: 2), () {
            showMessage('uri: $uri');
          }));

          return DeepLink.path(
            uri.path,
            includePrefixMatches: initial,
          );
        },
      ),
    );
  }
}

@RoutePage()
class MyHomePage extends StatefulWidget {
  const MyHomePage({
    super.key,
  });

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() => setState(() => _counter += 1);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Home'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            const Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headlineMedium,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: const Icon(Icons.add),
      ),
    );
  }
}

@RoutePage()
class MySecondPage extends StatelessWidget {
  const MySecondPage({super.key});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('MySecondPage'),
      ),
    );
  }
}

2. Add new lines in Info.plist

<key>CFBundleURLTypes</key>
  <array>
   <dict>
    <key>CFBundleTypeRole</key>
    <string>Viewer</string>
    <key>CFBundleURLName</key>
    <string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
    <key>CFBundleURLSchemes</key>
    <array>
     <string>example</string>
    </array>
   </dict>
 </array>
 <key>FlutterDeepLinkingEnabled</key>
 <true/>

3. Run app with flutter run and close it

4. Use the following command to open a deep link:

xcrun simctl openurl booted example://x.com/second

Additional Context:

Flutter version: 3.22.2
On Flutter 3.22.3, 3.24.3 same