Flutterfire: 🐛 [firebase_auth] Firebase user object get overridden on multi - project authentication.

[Ma-Altaiir]

Bug report

Describe the bug
Authentication to a second non default firebase app gets the default auth user object to get overridden.

Steps to reproduce

Steps to reproduce the behavior:

1. Initialize default firebase app and auth instance.
2. Initialize second firebase app and auth instance for it.
3. authenticate with google sign in through the default auth and print user data.
4. authenticate with email and password , anonymous ... through the second auth instance and print both default and second users data, they will be the same, the default one gets overridden.
5. re sign in with google and then default user recovers its data, second user keeps its own data.

Expected behavior

I expected when authenticating through a second instance to get a second auth User instance completely independent from each other.

---

Code Sample

import 'package:firebase_auth/firebase_auth.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:google_sign_in/google_sign_in.dart';

class AuthExample {
  AuthExample._();
  static FirebaseApp defaultApp;
  static FirebaseAuth defaultAuth;
  static FirebaseApp secondApp;
  static FirebaseAuth secondAuth;
  static Future init() async {
    defaultApp = await Firebase.initializeApp();
    defaultAuth = FirebaseAuth.instance;
    secondApp = await Firebase.initializeApp(
      name: '[SECOND]',
      options: FirebaseOptions(
        appId: '1:3xxxxxxxxxxxxxxxxxxxxx',
        apiKey: 'Axxxxxxxxxxxxxxxxxxxxxxxxx',
        messagingSenderId: 'xxxxxxxxxxx',
        projectId: 'xxxxxxxxxxxxxxx',
      ),
    );
    secondAuth = FirebaseAuth.instanceFor(app: secondApp);
  }

  Future<void> signinDefault({bool silent = false}) async {
    GoogleSignInAccount googleSignInAccount;
    GoogleSignIn googleSignIn = GoogleSignIn(scopes: ['email', 'profile', 'openid']);
    if (silent) {
      googleSignInAccount = await googleSignIn.signInSilently();
    } else {
      googleSignInAccount = await googleSignIn.signIn();
    }
    GoogleSignInAuthentication authentication = await googleSignInAccount.authentication;
    GoogleAuthCredential credential =
        GoogleAuthProvider.credential(idToken: authentication.idToken, accessToken: authentication.accessToken);
    await defaultAuth.signInWithCredential(credential);
    print("[DEFAULT] : " + defaultAuth.currentUser.toString());
  }

  Future<void> signoutDefault() async {
    await defaultAuth.signOut();
  }

  Future<void> signinSecond() async {
    await secondAuth.signInWithEmailAndPassword(email: defaultAuth.currentUser.email, password: defaultAuth.currentUser.uid);

    print("[DEFAULT] : " + defaultAuth.currentUser.toString());
    print('-----------------------------------');
    print("[SECOND] : " + secondAuth.currentUser.toString());

    //Must re sign in with default auth to recover default User data
    await signinDefault(silent: true);

    print("[DEFAULT] : " + defaultAuth.currentUser.toString());
    print('-----------------------------------');
    print("[SECOND] : " + secondAuth.currentUser.toString());
  }

  Future<void> signoutSecond() async {
    await secondAuth.signOut();
    await secondApp.delete();
  }
}

Flutter doctor

Run flutter doctor and paste the output below:

Click To Expand

[√] Flutter (Channel stable, 1.20.2, on Microsoft Windows [Version 10.0.19041.508], locale en-US)
    • Flutter version 1.20.2 at C:\Flutter
    • Framework revision bbfbf1770c (5 weeks ago), 2020-08-13 08:33:09 -0700
    • Engine revision 9d5b21729f
    • Dart version 2.9.1


[√] Android toolchain - develop for Android devices (Android SDK version 30.0.1)
    • Android SDK at C:\Users\Abinn\AppData\Local\Android\sdk
    • Platform android-30, build-tools 30.0.1
    • Java binary at: C:\Android Studio\jre\bin\java
    • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b01)
    • All Android licenses accepted.

[√] Android Studio (version 4.0)
    • Android Studio at C:\Android Studio
    • Flutter plugin version 48.1.2
    • Dart plugin version 193.7361
    • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b01)

[√] Connected device (1 available)
    • SM M105G (mobile) • 5200f1e8d4dca669 • android-arm • Android 10 (API 29)

• No issues found!

---

Flutter dependencies

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

Click To Expand

- firebase_auth 0.18.0+1 [meta firebase_core firebase_core_platform_interface firebase_auth_platform_interface firebase_auth_web flutter]
- firebase_core 0.5.0 [firebase_core_platform_interface flutter quiver meta firebase_core_web]
- flutter 0.0.0 [characters collection meta typed_data vector_math sky_engine]
- google_sign_in 4.5.3 [google_sign_in_platform_interface flutter meta google_sign_in_web]

---

[russellwheatley]

Hi @Ma-Altaiir , please provide a reproducible example, please. Thank you.

[russellwheatley]

Thanks for the sample, @Ma-Altaiir, I was able to reproduce the bug 👍 . Quick tip though, it was only by luck that I noticed you'd updated your initial comment. I recommend writing a new comment so that other posters interested in the discussion are notified 👌 .