【Flutter】ユニットテストを作成する

前回記事のテストコードです。

test/application/usecases/get_user_test.dart

test/application/usecases/get_user_test.dart

import 'package:flutter_test/flutter_test.dart';
import 'package:sampleapp/application/usecases/get_user.dart';
import 'package:sampleapp/core/result/app_result.dart';
import 'package:sampleapp/domain/entities/repositories/user_repository.dart';
import 'package:sampleapp/domain/entities/user.dart';

class MockUserRepository implements UserRepository{
  @override
  Future<AppResult<User>> fetchUser() async{
    return const AppSuccess(
      User(name:'Test User'),
    );
  }
}

class MockFailureUserReposiotry implements UserRepository{
  @override
  Future<AppResult<User>> fetchUser() async{
    return const AppFailure(
      'ユーザー取得に失敗しました',
    );
  }
}

void main(){
  group('GetUser',(){
    test('RepositoryからUserを取得できる', ()async{
      final repository = MockUserRepository();
      final getUser = GetUser(repository);
      final result = await getUser();
      expect(result, isA<AppSuccess<User>>());
      final success = result as AppSuccess<User>;
      expect(success.data.name,'Test User');
    });
    test('Repositoryが失敗した場合はFailureを返す',()async{
      final repository = MockFailureUserReposiotry();
      final getUser = GetUser(repository);
      final result = await getUser();
      expect(result, isA<AppFailure<User>>());
      final failure = result as AppFailure<User>;
      expect(
        failure.message,
        'ユーザー取得に失敗しました',
      );
    });
  });
}

test/core/result/app_result_test.dart

test/core/result/app_result_test.dart

import 'package:flutter_test/flutter_test.dart';
import 'package:sampleapp/core/result/app_result.dart';

void main(){
  group('AppSuccess',(){
    test('dataを保持する',(){
      const result = AppSuccess<String>('success');
      expect(result.data,'success');
      expect(result, isA<AppSuccess<String>>());
    });
  });
  group('AppFailure',(){
    test('messageを保持する',(){
      const result = AppFailure<String>('error');
      expect(result.message,'error');
      expect(result,isA<AppFailure<String>>());
    });
  });
}

test/data/repositories/user_repository_impl_test.dart

test/data/repositories/user_repository_impl_test.dart

import 'package:flutter_test/flutter_test.dart';
import 'package:sampleapp/core/result/app_result.dart';
import 'package:sampleapp/data/repositories/user_repository_impl.dart';
import 'package:sampleapp/domain/entities/user.dart';

void main(){
  group('UserRepositoryImpl',(){
    test('ユーザーを取得するとAppSuccessを返す',()async{
      final repository = UserRepositoryImpl();
      final result = await repository.fetchUser();
      expect(result, isA<AppSuccess<User>>());
      final success = result as AppSuccess<User>;
      expect(success.data.name,'taro');
    });
  });
}

test/presentation/pages/home_page_test.dart

test/presentation/pages/home_page_test.dart

import 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:hooks_riverpod/hooks_riverpod.dart';

import 'package:sampleapp/core/result/app_result.dart';
import 'package:sampleapp/domain/entities/user.dart';
import 'package:sampleapp/presentation/pages/home_page.dart';
import 'package:sampleapp/presentation/providers/user_provider.dart';

void main() {
  group('HomePage', () {
    testWidgets(
      'ユーザー取得中はローディングが表示される',
          (tester) async {
        await tester.pumpWidget(
          ProviderScope(
            overrides: [
              userProvider.overrideWith(
                    (ref) async {
                  await Future.delayed(
                    const Duration(seconds: 1),
                  );

                  return const AppSuccess(
                    User(name: 'Test User'),
                  );
                },
              ),
            ],
            child: const MaterialApp(
              home: HomePage(),
            ),
          ),
        );

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

    testWidgets(
      'ユーザー取得に成功するとユーザー名が表示される',
          (tester) async {
        await tester.pumpWidget(
          ProviderScope(
            overrides: [
              userProvider.overrideWith(
                    (ref) async {
                  return const AppSuccess(
                    User(name: 'Test User'),
                  );
                },
              ),
            ],
            child: const MaterialApp(
              home: HomePage(),
            ),
          ),
        );

        await tester.pump();

        expect(
          find.text('こんにちは、Test Userさん！'),
          findsOneWidget,
        );
      },
    );

    testWidgets(
      'AppFailureの場合はエラーメッセージが表示される',
          (tester) async {
        await tester.pumpWidget(
          ProviderScope(
            overrides: [
              userProvider.overrideWith(
                    (ref) async {
                  return const AppFailure(
                    'ユーザー取得に失敗しました',
                  );
                },
              ),
            ],
            child: const MaterialApp(
              home: HomePage(),
            ),
          ),
        );

        await tester.pump();

        expect(
          find.text('ユーザー取得に失敗しました'),
          findsOneWidget,
        );
      },
    );

    testWidgets(
      'Provider自体がExceptionになった場合は予期しないエラーが表示される',
          (tester) async {
        await tester.pumpWidget(
          ProviderScope(
            overrides: [
              userProvider.overrideWith(
                    (ref) async {
                  throw Exception('Unexpected error');
                },
              ),
            ],
            child: const MaterialApp(
              home: HomePage(),
            ),
          ),
        );

        await tester.pump();

        expect(
          find.textContaining('予期しないエラー:'),
          findsOneWidget,
        );
      },
    );
  });
}

test/presentation/providers/user_provider_test.dart

test/presentation/providers/user_provider_test.dart

import 'package:sampleapp/core/result/app_result.dart';
import 'package:sampleapp/data/repositories/user_repository_impl.dart';
import 'package:sampleapp/domain/entities/repositories/user_repository.dart';
import 'package:sampleapp/domain/entities/user.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:hooks_riverpod/hooks_riverpod.dart';
import 'package:sampleapp/presentation/pages/home_page.dart';
import 'package:sampleapp/presentation/providers/user_provider.dart';

class MockUserRepository implements UserRepositoryImpl{
  Future<AppResult<User>> fetchUser() async{
    return const AppSuccess(
      User(name: 'Provider Test User'),
    );
  }
}

class MockFailureUserRepository implements UserRepository{
  @override
  Future<AppResult<User>> fetchUser()async{
    return const AppFailure(
      'Provider Test Error',
    );
  }
}

void main() {
  group('userRepositoryProvider', () {
    test('UserRepositoryを取得できる', () {
      final container = ProviderContainer();

      addTearDown(container.dispose);

      final repository = container.read(
        userRepositoryProvider,
      );

      expect(repository, isA<UserRepository>());
    });
  });

  group('getUserProvider', () {
    test('GetUserを取得できる', () {
      final container = ProviderContainer(
        overrides: [
          userRepositoryProvider.overrideWith(
                (ref) => MockUserRepository(),
          ),
        ],
      );

      addTearDown(container.dispose);

      final getUser = container.read(
        getUserProvider,
      );

      expect(getUser, isNotNull);
    });
  });

  group('userProvider', () {
    test('ユーザー取得に成功する', () async {
      final container = ProviderContainer(
        overrides: [
          userRepositoryProvider.overrideWith(
                (ref) => MockUserRepository(),
          ),
        ],
      );

      addTearDown(container.dispose);

      final result = await container.read(
        userProvider.future,
      );

      expect(result, isA<AppSuccess<User>>());

      final success = result as AppSuccess<User>;

      expect(
        success.data.name,
        'Provider Test User',
      );
    });

    test('ユーザー取得に失敗する', () async {
      final container = ProviderContainer(
        overrides: [
          userRepositoryProvider.overrideWith(
                (ref) => MockFailureUserRepository(),
          ),
        ],
      );

      addTearDown(container.dispose);

      final result = await container.read(
        userProvider.future,
      );

      expect(result, isA<AppFailure<User>>());

      final failure = result as AppFailure<User>;

      expect(
        failure.message,
        'Provider Test Error',
      );
    });
  });
}