Mock isn't a valid concrete implementation of FirebaseFirestore

[bynicodevelop]

Hello,

I integrated the latest version of Mockito into the saint of one of my apps.

I have a case where I am using Mockito with Flutter's FirebaseFirestore.

Here is my test case:

import 'package:app/models/private_tip_model.dart';
import 'package:app/repositories/private_tips_repository.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:mockito/mockito.dart';

main() {
  test("Doit permettre de retourer une liste de conseils par ordre de création",
      () async {
    // ARRANGE
    FirebaseFirestoreMock firebase = FirebaseFirestoreMock();
    CollectionReferenceMock collectionReferenceMock = CollectionReferenceMock();
    QueryMock queryMock = QueryMock();
    QuerySnapshotMock querySnapshotMock = QuerySnapshotMock();
    QueryDocumentSnapshotMock queryDocumentSnapshotMock = QueryDocumentSnapshotMock();

    when(queryDocumentSnapshotMock.id).thenReturn('0987654321');
    when(queryDocumentSnapshotMock.data()).thenReturn({
      'title': 'Tips 1',
      'content': 'Content 1',
      'createdAt': 1234567,
    });

    when(querySnapshotMock.docs).thenReturn([queryDocumentSnapshotMock]);

    when(queryMock.get())
        .thenAnswer((realInvocation) => Future.value(querySnapshotMock));

    when(collectionReferenceMock.orderBy(
      'createdAt',
      descending: true,
    )).thenReturn(queryMock);

    when(firebase.collection(PrivateTipsRepository.COLLECTION))
        .thenReturn(collectionReferenceMock);

    final PrivateTipsRepository privateTipsRepository =
        PrivateTipsRepository(firebase);

    // ACT
    List<PrivateTipModel> privateTips = await privateTipsRepository.tips;

    // ASSERT
    expect(privateTips.length, 1);
    expect(privateTips[0].uid, '0987654321');
    expect(privateTips[0].title, 'Tips 1');
    expect(privateTips[0].content, 'Content 1');
    expect(privateTips[0].createdAt, 1234567);
  });
}

class FirebaseFirestoreMock extends Mock implements FirebaseFirestore {}

// ignore: must_be_immutable
class CollectionReferenceMock extends Mock implements CollectionReference {}

class QuerySnapshotMock extends Mock implements QuerySnapshot {}

class QueryDocumentSnapshotMock extends Mock implements QueryDocumentSnapshot {}

class QueryMock extends Mock implements Query {}

Visual studio code shows me the following error on the class FirebaseFirestoreMock:

I understood well in your documentation that it was now necessary to create methods in the mocks.

But even if I create the method used in my test (collection), I still get this error.

Thanks.

[srawlins]

Duplicate of #354