Flutter依赖注入与状态管理插件riverpod_test的使用

Flutter应用中，良好的依赖注入和状态管理是构建高效、可维护应用程序的关键。riverpod_test 插件为Riverpod提供了一套测试工具，可以帮助开发者更容易地编写单元测试，确保状态管理和依赖注入逻辑的正确性。

Package

riverpod_test 是 felangel 的 bloc_test 端口，针对 Riverpod Providers 进行了修改。它帮助提高代码覆盖率，通过测试所有 Riverpod Providers 来确保你的应用逻辑无误。

Installation

对于Flutter项目：

flutter pub add --dev riverpod_test

对于Dart项目：

dart pub add --dev riverpod_test

Usage

testProvider

用于测试简单的provider。

import 'package:riverpod_test.dart';

testProvider(
  'expect [0]',
  provider: counterProvider,
  expect: () => [0],
);

final counterProvider = Provider<int>((ref) => 0);

testNotifier

用于测试使用Notifier的状态管理器。

testNotifier(
  'expect [2] when increment is called twice and skip: 1',
  provider: counterNotifierProvider,
  act: (notifier) => notifier
      ..increment()
      ..increment(),
  skip: 1,
  expect: () => [2],
);

final counterNotifierProvider =
    NotifierProvider<CounterNotifier, int>(CounterNotifier.new);

class CounterNotifier extends Notifier<int> {
  @override
  int build() => 0;

  void increment() => state++;
}

testAsyncNotifier

用于测试异步状态管理器。

testAsyncNotifier<CounterAsyncNotifier, int>(
  'expect [AsyncData(1)] when call increment',
  provider: counterAsyncNotifierProvider(0),
  act: (notifier) => notifier.increment(),
  expect: () => <AsyncValue<int>>[const AsyncData(1)],
);

final counterAsyncNotifierProvider =
    AsyncNotifierProviderFamily<CounterAsyncNotifier, int, int>(
  CounterAsyncNotifier.new,
);

class CounterAsyncNotifier extends FamilyAsyncNotifier<int, int> {
  @override
  FutureOr<int> build(int initialValue) => initialValue;

  void increment() => state = AsyncData(value + 1);
}

testResultProvider

用于测试返回结果类型的provider。

testResultProvider<Repository>(
  'expect [1] when incrementCounter is called',
  provider: repositoryProvider,
  act: (result) => result.incrementCounter(),
  expect: () => [1],
);

final repositoryProvider = Provider<Repository>((ref) => Repository());

class Repository {
  int incrementCounter() => 1;
}

testStateNotifier

用于测试使用StateNotifier的状态管理器。

testStateNotifier<CounterStateNotifier, int>(
  'expect [0] when decrement is called and seed: 1',
  provider: counterStateNotifierProvider,
  act: (notifier) => notifier.decrement(),
  seed: 1,
  wait: const Duration(milliseconds: 100),
  expect: () => <int>[0],
);

final counterStateNotifierProvider =
    StateNotifierProvider<CounterStateNotifier, int>(
  (ref) => CounterStateNotifier(),
);

class CounterStateNotifier extends StateNotifier<int> {
  CounterStateNotifier() : super(0);

  void increment() => state++;

  Future<void> decrement() async {
    await Future<void>.delayed(const Duration(milliseconds: 100));
    state--;
  }
}

示例代码

以下是一个完整的示例demo，展示了如何在实际项目中使用riverpod_test进行测试。

import 'dart:async';
import 'package:mocktail/mocktail.dart';
import 'package:riverpod/riverpod.dart';
import 'package:riverpod_test/riverpod_test.dart';
import 'package:test/test.dart';

class MockRepository extends Mock implements Repository {}

void main() {
  mainProvider();
  mainNotifier();
  mainResultProvider();
  mainStateNotifier();
}

void mainProvider() {
  group('counterProvider', () {
    testProvider<int>(
      'expect [0]',
      provider: counterProvider,
      expect: () => const <int>[0],
    );
  });

  group('counterRepositoryProvider', () {
    final mockRepository = MockRepository();

    testProvider<int>(
      'expect [5] from repository',
      overrides: [repositoryProvider.overrideWithValue(mockRepository)],
      setUp: () => when(mockRepository.incrementCounter).thenReturn(5),
      provider: counterRepositoryProvider,
      expect: () => const <int>[5],
    );
  });
}

void mainNotifier() {
  group('counterNotifierProvider', () {
    testNotifier<CounterNotifier, int>(
      'expect [1] when increment is called',
      provider: counterNotifierProvider,
      act: (notifier) => notifier.increment(),
      expect: () => const <int>[1],
    );

    testAsyncNotifier(
      'expect [AsyncData(2)] when increment is called with seed: AsyncData(1)',
      provider: counterAsyncNotifierProvider,
      seed: const AsyncData(1),
      act: (notifier) => notifier.increment(),
      expect: () => [const AsyncData(2)],
    );
  });
}

void mainResultProvider() {
  testResultProvider<Repository>(
    'expect [1] when incrementCounter is called',
    provider: repositoryProvider,
    act: (result) => result.incrementCounter(),
    expect: () => [1],
  );
}

void mainStateNotifier() {
  testStateNotifier(
    'expect [1, 2] when increment is called twice',
    provider: counterStateNotifierProvider,
    act: (notifier) => notifier
      ..increment()
      ..increment(),
    expect: () => [1, 2],
  );
}

final counterProvider = Provider<int>((ref) => 0);

final counterRepositoryProvider =
    Provider<int>((ref) => ref.watch(repositoryProvider).incrementCounter());

final counterNotifierProvider =
    NotifierProvider<CounterNotifier, int>(CounterNotifier.new);

final counterAsyncNotifierProvider =
    AsyncNotifierProvider<CounterAsyncNotifier, int>(CounterAsyncNotifier.new);

final repositoryProvider = Provider<Repository>((ref) => Repository());

final counterStateNotifierProvider =
    StateNotifierProvider<CounterStateNotifier, int>(
  (ref) => CounterStateNotifier(),
);

class CounterNotifier extends Notifier<int> {
  @override
  int build() => 0;

  void increment() => state++;
}

class CounterAsyncNotifier extends AsyncNotifier<int> {
  @override
  FutureOr<int> build() => 0;

  void increment() => state = AsyncData(state.value! + 1);
}

class Repository {
  int incrementCounter() => 1;
}

class CounterStateNotifier extends StateNotifier<int> {
  CounterStateNotifier() : super(0);

  void increment() => state++;
}

通过上述内容，您可以了解如何在Flutter项目中使用riverpod_test进行依赖注入和状态管理的测试。希望这些信息对您有所帮助！