firebase - 如何在 flutter 中模拟 FirebaseApp

Question

我正在尝试测试使用 FirebaseFirestore 的方法，但我无法模拟 FirebaseFirestore.instance 属性。
我正在关注这些例子:

初始化内核:https://firebase.flutter.dev/docs/overview#initializing-flutterfire

使用 firestore 插件:https://firebase.flutter.dev/docs/firestore/usage

我正在为我的类(class)使用下面的代码，它运行良好，这意味着 firestoreInstance 已正确加载

import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/material.dart';

void main() {
  WidgetsFlutterBinding.ensureInitialized();
  runApp(
    Main(firebaseApp: Firebase.initializeApp()),
  );
}

class Main extends StatelessWidget {
  final Future<FirebaseApp> firebaseApp;
  const Main({this.firebaseApp});

  @override
  Widget build(BuildContext context) {
    return FutureBuilder(
      future: firebaseApp,
      builder: (context, snapshot) {
        if (snapshot.connectionState == ConnectionState.done) {
          final firestoreInstance = FirebaseFirestore.instanceFor(
            app: snapshot.data,
          );
          return MyWidget();
        }
        return CircularProgressIndicator();
      },
    );
  }
}

但是当我运行下面的测试时，我收到了消息:
“在构建 Builder(dirty) 时抛出了以下 FirebaseException:
[core/no-app] 没有创建 Firebase 应用“[DEFAULT]” - 调用 Firebase.initializeApp()”

import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:mockito/mockito.dart';

class MockFirebaseApp extends Mock implements FirebaseApp {}

void main() {
  FirebaseApp firebaseApp;

  setUp(() async {
    TestWidgetsFlutterBinding.ensureInitialized();
    firebaseApp = MockFirebaseApp();
  });

  group('Main', () {
    testWidgets('Loads my widget', (WidgetTester tester) async {
      await tester.runAsync(() async {
        await tester.pumpWidget(
          Main(firebaseApp: Future.value(firebaseApp)),
        );

        expect(find.byType(CircularProgressIndicator), findsOneWidget);
      });
    });
  });
}

Answer 1

我有同样的问题。使用 this answer我找到了解决方案。

复制内容:https://github.com/FirebaseExtended/flutterfire/blob/master/packages/firebase_auth/firebase_auth/test/mock.dart到一个文件中，您可以将其导入到您的测试中，您需要在其中初始化 Firebase 应用程序。

调用 setupFirebaseAuthMocks();在您的顶部 main用于所有测试的功能。

在您的 setUpAll函数，调用 await Firebase.initializeApp(); (你也可以把它放在你的 main 函数下 setupFirebaseAuthMocks(); 仍然有效)。

现在你应该有一个模拟的 Firebase 应用程序。
这是一个完整的例子:

import 'package:flutter/material.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:flutter_test/flutter_test.dart';
import '../lib/authentication/your_auth_using_firebase.dart';
import './mock.dart'; // from: https://github.com/FirebaseExtended/flutterfire/blob/master/packages/firebase_auth/firebase_auth/test/mock.dart



void main() {
  // TestWidgetsFlutterBinding.ensureInitialized(); Gets called in setupFirebaseAuthMocks()
  setupFirebaseAuthMocks();

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

  testWidgets('Your Test', (WidgetTester tester) async {
    final YourFirebaseAuthClass authService = YourFirebaseAuthClass();
    // Tests to write
  });
}