Question 118901 in Firebase Question posted in
An extensive official documentation can be found here.

Widget Test – "MethodChannelFirebase.channel" the getter channel isn't defined for the type MethodChannelFirebase. What is the current best practice?

Previously I used the following code to ensure Firebase was initialised …

    typedef Callback = void Function(MethodCall call);

void setupFirebaseAuthMocks([Callback? customHandlers]) {
  TestWidgetsFlutterBinding.ensureInitialized();

  setupFirebaseCoreMocks();

  ///todo fix this
  MethodChannelFirebase.channel.setMockMethodCallHandler((call) async {
    if (call.method == 'Firebase#initializeCore') {
      return [
        {
          'name': defaultFirebaseAppName,
          'options': {
            'apiKey': '123',
            'appId': '123',
            'messagingSenderId': '123',
            'projectId': '123',
          },
          'pluginConstants': {},
        }
      ];
    }

    if (call.method == 'Firebase#initializeApp') {
      return {
        'name': call.arguments['appName'],
        'options': call.arguments['options'],
        'pluginConstants': {},
      };
    }

    if (customHandlers != null) {
      customHandlers(call);
    }

    return null;
  });
}

This no longer works since I updated to the latest version of firebase_core :

firebase_core: ^2.9.0
# firebase_core: ^1.3.0
cloud_firestore: ^4.5.0

The static analyser says the getter channel isn’t defined for the type MethodChannelFirebase … and my tests can’t run without:

setupFirebaseAuthMocks();

  setUpAll(() async {
    await Firebase.initializeApp();
  });

I also tried (as is the new requirement for firebase_core in the main application):

//setupFirebaseAuthMocks();

  setUpAll(() async {
    await Firebase.initializeApp(
      options: DefaultFirebaseOptions.currentPlatform,
    );
  });

There doesn’t seem to be an obvious answer on here or in the docs… pointing me in the right direction would be greatly appreciated!

Tags:

2

Answers


  1. Chosen as BEST ANSWER
    0

    Posting my own answer in case anyone else benefits!

    The bottom line is you don't need to initialise App for a test anymore

    Firebase.initializeApp(); //not required

    Instead you must make sure that any time you call firebase in your app during a test that it has a suitable mock provided. If a suitable mock is provided then you can avoid the error message:

    [core/no-app] No Firebase App '[DEFAULT]' has been created - call Firebase.initializeApp()

    An example of how to provide a mock is as follows

        import 'package:fake_cloud_firestore/fake_cloud_firestore.dart';

    final FakeFirebaseFirestore fakeFirebaseFirestoreManufacturersCollection = FakeFirebaseFirestore();

    initialiseFirestoreManufacturersCollectionFake() async {
  List<Manufacturer> testManufacturerList = [];

  testManufacturerList.add(Manufacturer(
      keyword: "none",
      id: "testManf1",
      countryOfOrigin: "United Kingdom",
      manufacturingLocations: [],
      distribution: [],
  ));

  testManufacturerList.forEach((manufacturer) async {
    await fakeFirebaseFirestoreManufacturersCollection
        .collection(FirestoreManufacturerUtils.manufacturersCollection)
        .doc(manufacturer.id)
        .set(manufacturer.toJson());
  });
}

main(){

  TestWidgetsFlutterBinding.ensureInitialized();
  
  

  setUpAll(() async {
    //await Firebase.initializeApp(); //no need for this anymore!
  });


  Widget testAppMultiTab({Widget? child}){

    ///before anything initialise the Firestore singleton with a Fake
    initialiseFirestoreManufacturersCollectionFake();
    var fakeFirebaseFirestoreManufacturersCollection = FirestoreFakerUtil.fakeFirebaseFirestoreManufacturersCollection;
    manufacturerInfo = ManufacturerInformation(firestore: fakeFirebaseFirestoreManufacturersCollection);
    
    return MaterialApp(
      home: Scaffold(
          body: ScopedModel<ManufacturerInformation>(model: manufacturerInfo,child: MaterialApp(
                        title: 'Manufacturing app',
                        home: HomeScreen(),
                      ),
                    ),
                  ),
                ),
              ))
      ),
    );
  }

  group("some tests which involve firestore calls", (){
  //...
  })
}

    `

    Hopefully this will help someone out there!!


  2. 0

    Yes, there are some breaking changes in the firebase core platform interface api.

    You need to add following. It will work.

    import 'package:firebase_core_platform_interface/firebase_core_platform_interface.dart';
import 'package:flutter/services.dart';
import 'package:flutter_test/flutter_test.dart';

void setupFirebaseAuthMocks([Callback? customHandlers]) {
  TestWidgetsFlutterBinding.ensureInitialized();

  setupFirebaseCoreMocks();
}

    You can remove following method as channel is removed from latest dependency.

    MethodChannelFirebase.channel.setMockMethodCallHandler((call) async { 

});
    Login or Signup to reply.
Please signup or login to give your own answer.

Back To Top
Search