🐛 [firebase_ui_auth] Login via google after deleting email account triggers error

[Jamie-505]

Bug report

When you delete an email account from the profile page and land back on the sign-in page, choosing sign-in with Google results in nothing happening. But when you reload the app you're signed in.

Error message:

E/flutter (21971): [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: Null check operator used on a null value
E/flutter (21971): #0      EmailVerificationController.user (package:firebase_ui_auth/src/email_verification.dart:68:36)
E/flutter (21971): firebase/flutterfire#1      EmailVerificationController.reload (package:firebase_ui_auth/src/email_verification.dart:82:11)
E/flutter (21971): firebase/flutterfire#2      EmailVerificationController.didChangeAppLifecycleState (package:firebase_ui_auth/src/email_verification.dart:63:7)
E/flutter (21971): firebase/flutterfire#3      WidgetsBinding.handleAppLifecycleStateChanged (package:flutter/src/widgets/binding.dart:673:16)
E/flutter (21971): firebase/flutterfire#4      ServicesBinding._handleLifecycleMessage (package:flutter/src/services/binding.dart:262:5)
E/flutter (21971): firebase/flutterfire#5      BasicMessageChannel.setMessageHandler.<anonymous closure> (package:flutter/src/services/platform_channel.dart:214:49)
E/flutter (21971): firebase/flutterfire#6      _DefaultBinaryMessenger.setMessageHandler.<anonymous closure> (package:flutter/src/services/binding.dart:393:35)
E/flutter (21971): firebase/flutterfire#7      _invoke2 (dart:ui/hooks.dart:183:13)
E/flutter (21971): firebase/flutterfire#8      _ChannelCallbackRecord.invoke (dart:ui/channel_buffers.dart:40:5)
E/flutter (21971): firebase/flutterfire#9      _Channel.push (dart:ui/channel_buffers.dart:130:31)
E/flutter (21971): firebase/flutterfire#10     ChannelBuffers.push (dart:ui/channel_buffers.dart:326:17)
E/flutter (21971): firebase/flutterfire#11     PlatformDispatcher._dispatchPlatformMessage (dart:ui/platform_dispatcher.dart:664:22)
E/flutter (21971): firebase/flutterfire#12     _dispatchPlatformMessage (dart:ui/hooks.dart:86:31)
E/flutter (21971): 

Steps to reproduce

Steps to reproduce the behavior:

1. Have your sign-in event trigger redirect to profile page with

AuthStateChangeAction<SignedIn>((context, state) {
  Navigator.pushReplacementNamed(context, '$profileRoute');
}),

2. Have your sign-out action ont the profile screen route back to the sign-in page and delete the stack (to prevent user from going back to previous screens) like:

ProfileScreen(
// ... appBar etc.
  actions: [
    SignedOutAction((context) {
      Navigator.pushAndRemoveUntil(context,
        MaterialPageRoute(builder: (BuildContext context) {
          return const SignInScreen();
        }), (r) {
          return false;
        });
    })
  ],
)

3. register with email
4. delete account on profile page (should bring you back to sign-in screen)
5. click on sign-in with Google and sign-in with Google account
6. be stuck on sign-in screen (with logs showing the mentioned stacktrace)

Expected behavior

Step 5 in reproduce should redirect to profile page

---

Flutter doctor

Run flutter doctor and paste the output below:

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Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel stable, 3.7.10, on macOS 13.3 22E252 darwin-arm64, locale en-DE)
[✓] Android toolchain - develop for Android devices (Android SDK version 33.0.2)
[✓] Xcode - develop for iOS and macOS (Xcode 14.3)
[✓] Chrome - develop for the web
[!] Android Studio (not installed)
[✓] IntelliJ IDEA Ultimate Edition (version 2022.3.1)
[✓] IntelliJ IDEA Ultimate Edition (version 2022.2.3)
[✓] IntelliJ IDEA Ultimate Edition (version 2022.3.1)
[✓] VS Code (version 1.74.0)
[✓] Connected device (3 available)
[✓] HTTP Host Availability

---

Flutter dependencies

Run flutter pub deps -- --style=compact and paste the output below:

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Dart SDK 2.19.6
Flutter SDK 3.7.10
butterfly 1.0.0+1

dependencies:
- firebase_auth 4.4.0 [firebase_auth_platform_interface firebase_auth_web firebase_core firebase_core_platform_interface flutter meta]
- firebase_core 2.9.0 [firebase_core_platform_interface firebase_core_web flutter meta]
- firebase_database 10.1.0 [firebase_core firebase_core_platform_interface firebase_database_platform_interface firebase_database_web flutter]
- firebase_dynamic_links 5.1.0 [firebase_core firebase_core_platform_interface firebase_dynamic_links_platform_interface flutter meta plugin_platform_interface]
- firebase_ui_auth 1.2.0 [email_validator firebase_auth firebase_core firebase_dynamic_links firebase_ui_localizations firebase_ui_oauth firebase_ui_shared flutter flutter_localizations flutter_svg]
- firebase_ui_oauth_google 1.0.21 [firebase_auth firebase_ui_oauth flutter google_sign_in]
- flutter 0.0.0 [characters collection js material_color_utilities meta vector_math sky_engine]
- google_fonts 4.0.3 [flutter http path_provider crypto]
- google_sign_in 5.4.4 [flutter google_sign_in_android google_sign_in_ios google_sign_in_platform_interface google_sign_in_web]
- intl 0.17.0 [clock path]
- wear 1.1.0 [flutter]

dev dependencies:
- flutter_lints 2.0.1 [lints]
- flutter_test 0.0.0 [flutter test_api path fake_async clock stack_trace vector_math async boolean_selector characters collection js matcher material_color_utilities meta source_span stream_channel string_scanner term_glyph]

transitive dependencies:
- _flutterfire_internals 1.1.0 [collection firebase_core firebase_core_platform_interface flutter meta]
- async 2.10.0 [collection meta]
- boolean_selector 2.1.1 [source_span string_scanner]
- characters 1.2.1
- clock 1.1.1
- collection 1.17.0
- crypto 3.0.2 [typed_data]
- desktop_webview_auth 0.0.11 [crypto flutter http flutter_web_plugins plugin_platform_interface]
- email_validator 2.1.17
- fake_async 1.3.1 [clock collection]
- ffi 2.0.1
- file 6.1.4 [meta path]
- firebase_auth_platform_interface 6.13.0 [_flutterfire_internals collection firebase_core flutter meta plugin_platform_interface]
- firebase_auth_web 5.3.0 [firebase_auth_platform_interface firebase_core firebase_core_web flutter flutter_web_plugins http_parser intl js meta]
- firebase_core_platform_interface 4.6.0 [collection flutter flutter_test meta plugin_platform_interface]
- firebase_core_web 2.3.0 [firebase_core_platform_interface flutter flutter_web_plugins js meta]
- firebase_database_platform_interface 0.2.3 [_flutterfire_internals collection firebase_core flutter meta plugin_platform_interface]
- firebase_database_web 0.2.2 [firebase_core firebase_core_web firebase_database_platform_interface flutter flutter_web_plugins js]
- firebase_dynamic_links_platform_interface 0.2.4 [_flutterfire_internals firebase_core flutter meta plugin_platform_interface]
- firebase_ui_localizations 1.3.0 [flutter flutter_localizations intl path]
- firebase_ui_oauth 1.2.0 [desktop_webview_auth firebase_auth firebase_ui_auth firebase_ui_shared flutter_svg flutter]
- firebase_ui_shared 1.1.0 [flutter]
- flutter_localizations 0.0.0 [flutter intl characters clock collection js material_color_utilities meta path vector_math]
- flutter_svg 1.1.6 [flutter meta path_drawing vector_math xml]
- flutter_web_plugins 0.0.0 [flutter js characters collection material_color_utilities meta vector_math]
- google_sign_in_android 6.1.8 [flutter google_sign_in_platform_interface]
- google_sign_in_ios 5.6.1 [flutter google_sign_in_platform_interface]
- google_sign_in_platform_interface 2.4.0 [flutter plugin_platform_interface quiver]
- google_sign_in_web 0.10.2+1 [flutter flutter_web_plugins google_sign_in_platform_interface js]
- http 0.13.5 [async http_parser meta path]
- http_parser 4.0.2 [collection source_span string_scanner typed_data]
- js 0.6.5 [meta]
- lints 2.0.1
- matcher 0.12.13 [meta stack_trace]
- material_color_utilities 0.2.0
- meta 1.8.0
- path 1.8.2
- path_drawing 1.0.1 [vector_math meta path_parsing flutter]
- path_parsing 1.0.1 [vector_math meta]
- path_provider 2.0.14 [flutter path_provider_android path_provider_foundation path_provider_linux path_provider_platform_interface path_provider_windows]
- path_provider_android 2.0.24 [flutter path_provider_platform_interface]
- path_provider_foundation 2.2.1 [flutter path_provider_platform_interface]
- path_provider_linux 2.1.10 [ffi flutter path path_provider_platform_interface xdg_directories]
- path_provider_platform_interface 2.0.6 [flutter platform plugin_platform_interface]
- path_provider_windows 2.1.5 [ffi flutter path path_provider_platform_interface win32]
- petitparser 5.1.0 [meta]
- platform 3.1.0
- plugin_platform_interface 2.1.4 [meta]
- process 4.2.4 [file path platform]
- quiver 3.2.1 [matcher]
- sky_engine 0.0.99
- source_span 1.9.1 [collection path term_glyph]
- stack_trace 1.11.0 [path]
- stream_channel 2.1.1 [async]
- string_scanner 1.2.0 [source_span]
- term_glyph 1.2.1
- test_api 0.4.16 [async boolean_selector collection meta source_span stack_trace stream_channel string_scanner term_glyph matcher]
- typed_data 1.3.1 [collection]
- vector_math 2.1.4
- win32 3.1.3 [ffi]
- xdg_directories 1.0.0 [meta path process]
- xml 6.2.2 [collection meta petitparser]

---

[FMorschel]

I'm unsure how to solve this, but I just want to put out here what I was having trouble with. Seems to be related.

When you first select an email with the Google Sign-in button, it keeps it cached somewhere and to this moment, I was not able to find any configuration option so that I could potentially log in with a different email. Say I needed to log into another account that also only has Google Sing-in enabled for example.

Only able to clean this cached email by cleaning the app's full data. Not even cache only.

[FMorschel]

Looking inside the package, I found a signInSilently method inside GoogleSignIn. Couldn`t find if it's been called. But that could probably be the issue here. See the docs:

Attempts to sign in a previously authenticated user without interaction.

Returned Future resolves to an instance of [GoogleSignInAccount] for a
successful sign in or null if there is no previously authenticated user.
Use [signIn] method to trigger interactive sign in process.

Authentication is triggered if there is no currently signed in
user (that is when currentUser == null), otherwise this method returns
a Future which resolves to the same user instance.

Re-authentication can be triggered after [signOut] or [disconnect]. It can
also be triggered by setting [reAuthenticate] to true if a new ID token
is required.

When [suppressErrors] is set to false and an error occurred during sign in
returned Future completes with [PlatformException] whose code can be
one of [kSignInRequiredError] (when there is no authenticated user) ,
[kNetworkError] (when a network error occurred) or [kSignInFailedError]
(when an unknown error occurred).

[FMorschel]

Found a solution. Missing the call to disconnect. I added it inside a FirebaseAuth.instance.authStateChanges().listen call when the user is null at the start of my app. This means that the user has logged out.

I'm currently using:

  final googleProvider = GoogleProvider(clientId: googleClientID);
  FirebaseUIAuth.configureProviders([
    googleProvider,
    PhoneAuthProvider(),
    EmailAuthProvider(),
  ]);
  runApp(MainApp(googleProvider: googleProvider));

I'm not sure if this works in any GoogleProvider or if it has to be the one used. So just be aware of it.

[github-actions]

Hello 👋, to help manage issues we automatically close stale issues.

This issue has been automatically marked as stale because it has not had activity for quite some time. Has this issue been fixed, or does it still require attention?

This issue will be closed in 15 days if no further activity occurs.

Thank you for your contributions.