测试 Worker 实现

WorkManager 提供了用于测试 Worker、ListenableWorker 和 ListenableWorker 变体（CoroutineWorker 和 RxWorker）的 API。

测试 worker

假设我们有一个类似以下示例的 Worker：

Kotlin

class SleepWorker(context: Context, parameters: WorkerParameters) :
    Worker(context, parameters) {

    override fun doWork(): Result {
        // Sleep on a background thread.
        Thread.sleep(1000)
        return Result.success()
    }
}

Java

public class SleepWorker extends Worker {
    public SleepWorker(
            @NonNull Context context,
            @NonNull WorkerParameters workerParameters) {
        super(context, workerParameters);
    }

    @NonNull
    @Override
    public Result doWork() {
        try {
            Thread.sleep(1000);
        } catch (InterruptedException ignore) {
return Result.success();
        }
    }
}

如需测试这个 Worker，您可以使用 TestWorkerBuilder。此构建器有助于构建可用于测试业务逻辑的 Worker 实例。

Kotlin

// Kotlin code uses the TestWorkerBuilder extension to build
// the Worker
@RunWith(AndroidJUnit4::class)
class SleepWorkerTest {
    private lateinit var context: Context
    private lateinit var executor: Executor

    @Before
    fun setUp() {
        context = ApplicationProvider.getApplicationContext()
        executor = Executors.newSingleThreadExecutor()
    }

    @Test
    fun testSleepWorker() {
        val worker = TestWorkerBuilder<SleepWorker>(
            context = context,
            executor = executor
        ).build()

        val result = worker.doWork()
        assertThat(result, `is`(Result.success()))
    }
}

Java

@RunWith(AndroidJUnit4.class)
public class SleepWorkerJavaTest {
    private Context context;
    private Executor executor;

    @Before
    public void setUp() {
        context = ApplicationProvider.getApplicationContext();
        executor = Executors.newSingleThreadExecutor();
    }

    @Test
    public void testSleepWorker() {
        SleepWorker worker =
                (SleepWorker) TestWorkerBuilder.from(context,
                        SleepWorker.class,
                        executor)
                        .build();

        Result result = worker.doWork();
        assertThat(result, is(Result.success()));
    }
}

TestWorkerBuilder 也可用于设置标记（例如 inputData 或 runAttemptCount），以便您单独验证工作器状态。例如，SleepWorker 将休眠时长当作输入数据而非 worker 中定义的常量数据：

Kotlin

class SleepWorker(context: Context, parameters: WorkerParameters) :
    Worker(context, parameters) {

    override fun doWork(): Result {
        // Sleep on a background thread.
        val sleepDuration = inputData.getLong(SLEEP_DURATION, 1000)
        Thread.sleep(sleepDuration)
        return Result.success()
    }

    companion object {
        const val SLEEP_DURATION = "SLEEP_DURATION"
    }
}

Java

public class SleepWorker extends Worker {
    public static final String SLEEP_DURATION = "SLEEP_DURATION";

    public SleepWorker(
            @NonNull Context context,
            @NonNull WorkerParameters workerParameters) {
        super(context, workerParameters);
    }

    @NonNull
    @Override
    public Result doWork() {
        try {
            long duration = getInputData().getLong(SLEEP_DURATION, 1000);
            Thread.sleep(duration);
        } catch (InterruptedException ignore) {
       return Result.success();
        }
    }
}

在 SleepWorkerTest 中，您可以将该输入数据提供给 TestWorkerBuilder，以满足 SleepWorker 的需求。

Kotlin

// Kotlin code uses the TestWorkerBuilder extension to build
// the Worker
@RunWith(AndroidJUnit4::class)
class SleepWorkerTest {
    private lateinit var context: Context
    private lateinit var executor: Executor

    @Before
    fun setUp() {
        context = ApplicationProvider.getApplicationContext()
        executor = Executors.newSingleThreadExecutor()
    }

    @Test
    fun testSleepWorker() {
        val worker = TestWorkerBuilder<SleepWorker>(
            context = context,
            executor = executor,
            inputData = workDataOf("SLEEP_DURATION" to 1000L)
        ).build()

        val result = worker.doWork()
        assertThat(result, `is`(Result.success()))
    }
}

Java

@RunWith(AndroidJUnit4.class)
public class SleepWorkerJavaTest {
    private Context context;
    private Executor executor;

    @Before
    public void setUp() {
        context = ApplicationProvider.getApplicationContext();
        executor = Executors.newSingleThreadExecutor();
    }

    @Test
    public void testSleepWorker() {
        Data inputData = new Data.Builder()
                .putLong("SLEEP_DURATION", 1000L)
                .build();

        SleepWorker worker =
                (SleepWorker) TestWorkerBuilder.from(context,
                        SleepWorker.class, executor)
                        .setInputData(inputData)
                        .build();

        Result result = worker.doWork();
        assertThat(result, is(Result.success()));
    }
}

如需详细了解 TestWorkerBuilder API，请参阅 TestListenableWorkerBuilder（TestWorkerBuilder 的父类）的参考页面。

测试 ListenableWorker 及其变体

如需测试 ListenableWorker 或其变体（CoroutineWorker 和 RxWorker），请使用 TestListenableWorkerBuilder。TestWorkerBuilder 和 TestListenableWorkerBuilder 的主要区别在于，TestWorkerBuilder 允许指定用来运行 Worker 的后台 Executor，而 TestListenableWorkerBuilder 依赖 ListenableWorker 实现的线程逻辑。

例如，假设我们需要测试类似以下示例的 CoroutineWorker：

class SleepWorker(context: Context, parameters: WorkerParameters) :
    CoroutineWorker(context, parameters) {
    override suspend fun doWork(): Result {
        delay(1000L) // milliseconds
        return Result.success()
    }
}

为了测试 SleepWorker，我们首先使用 TestListenableWorkerBuilder 创建一个工作器实例，然后在协程中调用其 doWork 函数。

@RunWith(AndroidJUnit4::class)
class SleepWorkerTest {
    private lateinit var context: Context

    @Before
    fun setUp() {
        context = ApplicationProvider.getApplicationContext()
    }

    @Test
    fun testSleepWorker() {
        val worker = TestListenableWorkerBuilder<SleepWorker>(context).build()
        runBlocking {
            val result = worker.doWork()
            assertThat(result, `is`(Result.success()))
        }
    }
}

runBlocking 可用作测试的协程构建器，使任何异步执行的代码都转为并行运行。

测试 RxWorker 实现类似于测试 CoroutineWorker，因为 TestListenableWorkerBuilder 可以处理 ListenableWorker 的任何子类。假设某个版本的 SleepWorker 使用 RxJava 而非协程。

Kotlin

class SleepWorker(
    context: Context,
    parameters: WorkerParameters
) : RxWorker(context, parameters) {
    override fun createWork(): Single<Result> {
        return Single.just(Result.success())
            .delay(1000L, TimeUnit.MILLISECONDS)
    }
}

Java

public class SleepWorker extends RxWorker {
    public SleepWorker(@NonNull Context appContext, 
@NonNull WorkerParameters workerParams) {
        super(appContext, workerParams);
    }

    @NonNull
    @Override
    public Single<Result> createWork() {
        return Single.just(Result.success())
                .delay(1000L, TimeUnit.MILLISECONDS);
    }
}

测试 RxWorker 的 SleepWorkerTest 版本可能类似于测试 CoroutineWorker 的版本。您使用相同的 TestListenableWorkerBuilder，但现在会调用 RxWorker 的 createWork 函数。createWork 会返回一个 Single，可用于验证工作器的行为。TestListenableWorkerBuilder 可处理线程方面的任何复杂问题，还能并行执行工作器代码。

Kotlin

@RunWith(AndroidJUnit4::class)
class SleepWorkerTest {
    private lateinit var context: Context

    @Before
    fun setUp() {
        context = ApplicationProvider.getApplicationContext()
    }

    @Test
    fun testSleepWorker() {
        val worker = TestListenableWorkerBuilder<SleepWorker>(context).build()
        worker.createWork().subscribe { result ->
            assertThat(result, `is`(Result.success()))
        }
    }
}

Java

@RunWith(AndroidJUnit4.class)
public class SleepWorkerTest {
    private Context context;

    @Before
    public void setUp() {
        context = ApplicationProvider.getApplicationContext();
    }

    @Test
    public void testSleepWorker() {
        SleepWorker worker = TestListenableWorkerBuilder.from(context, SleepWorker.class)
                .build();
        worker.createWork().subscribe(result ->
                assertThat(result, is(Result.success())));
        }
}