Introduce tests

* Update testing dependencies
* Add testing dependencies to WorkManager sample
* Add CleanupWorkerTest
* Add Test for BaseFilterWorker
* Test periodic execution

BasicRxJavaSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

BasicRxJavaSampleKotlin/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

BasicSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

GithubBrowserSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

LiveDataSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

MADSkillsNavigationSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

NavigationAdvancedSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

NavigationBasicSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

PagingSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

PagingWithNetworkSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

PersistenceContentProviderSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

PersistenceMigrationsSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

ViewBindingSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

WorkManagerSample/lib/build.gradle

@@ -55,4 +55,10 @@ dependencies {
     implementation deps.glide.runtime
 
     testImplementation deps.junit
+
+    androidTestImplementation deps.atsl.ext_junit_ktx
+    androidTestImplementation deps.atsl.runner
+    androidTestImplementation deps.atsl.rules
+
+    androidTestImplementation deps.work.testing
 }

WorkManagerSample/lib/src/androidTest/java/com/example/background/workers/CleanupWorkerTest.kt

+/*
+ * Copyright 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.background.workers
+
+import android.content.Context
+import androidx.test.core.app.ApplicationProvider
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.work.Constraints
+import androidx.work.PeriodicWorkRequestBuilder
+import androidx.work.WorkInfo
+import androidx.work.WorkManager
+import androidx.work.testing.TestListenableWorkerBuilder
+import androidx.work.testing.WorkManagerTestInitHelper
+import kotlinx.coroutines.runBlocking
+import org.junit.After
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import java.io.File
+import java.io.FilenameFilter
+import java.util.concurrent.TimeUnit.HOURS
+
+/** Tests for [CleanupWorker]. */
+@RunWith(AndroidJUnit4::class)
+class CleanupWorkerTest {
+
+    private var context: Context = ApplicationProvider.getApplicationContext()
+    private lateinit var worker: CleanupWorker
+
+    @Before
+    fun setUp() {
+        worker = TestListenableWorkerBuilder<CleanupWorker>(context).build()
+    }
+
+    @After
+    fun tearDown() {
+        val existingFiles = listFilesInTargetDir() ?: return
+        for (file in existingFiles) {
+            file.delete()
+        }
+    }
+
+    @Test
+    fun testPeriodicCleanup() {
+        WorkManagerTestInitHelper.initializeTestWorkManager(context)
+        val testDriver = WorkManagerTestInitHelper.getTestDriver(context)!!
+        val workManager = WorkManager.getInstance(context)
+
+        val constraints = Constraints.Builder()
+            .setRequiresCharging(true)
+            .setRequiresBatteryNotLow(true)
+            .setRequiresDeviceIdle(true).build()
+
+        val request = PeriodicWorkRequestBuilder<CleanupWorker>(24, HOURS)
+            .setConstraints(constraints).build()
+
+        workManager.enqueue(request).result.get()
+
+        with(testDriver) {
+            setPeriodDelayMet(request.id)
+            setAllConstraintsMet(request.id)
+        }
+
+        val workInfo = workManager.getWorkInfoById(request.id).get()
+
+        assertEquals(workInfo.state, WorkInfo.State.RUNNING)
+    }
+
+    @Test
+    fun testCleanupWorker_pngAreRemoved() {
+        // Create an empty test file that should be caught by CleanupWorker and removed
+        for (i in 0..9) {
+            createFileUnderTest("test$i.png")
+        }
+
+        // Run test
+        runBlocking {
+            worker.doWork()
+        }
+
+        // Assert that file has been removed
+        val remainingFiles = countPngInTargetDir()
+        assertTrue(remainingFiles == 0)
+    }
+
+    @Test
+    fun testCleanupWorker_nonPngRemain() {
+        // Create an empty test file that should NOT be caught by CleanupWorker and removed
+        for (i in 0..9) {
+            createFileUnderTest("test$i")
+            createFileUnderTest("test$i.png")
+        }
+        //Run test
+        runBlocking {
+            worker.doWork()
+        }
+
+        val existingPng = countPngInTargetDir()
+        assertTrue(existingPng == 0)
+        val existingFiles = countFilesInTargetDir()
+        assertTrue(existingFiles == 10)
+    }
+
+    /** Create the file for testing the [CleanupWorker]. */
+    private fun createFileUnderTest(fileName: String): File {
+        val testFile = File("${worker.targetDirectory.path}/$fileName")
+        testFile.createNewFile()
+        assertTrue("Created file doesn't exist", testFile.exists())
+        return testFile
+    }
+
+    private fun listFilesInTargetDir(filter: FilenameFilter? = null) =
+        worker.targetDirectory.listFiles(filter)
+
+    private fun countFilesInTargetDir(filter: FilenameFilter? = null) =
+        listFilesInTargetDir(filter)?.size
+
+    private fun countPngInTargetDir() =
+        listFilesInTargetDir { _, name -> name.endsWith(".png") }?.size
+}
\ No newline at end of file

WorkManagerSample/lib/src/androidTest/java/com/example/background/workers/filters/BaseFilterWorkerTest.kt

+/*
+ * Copyright 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example.background.workers.filters
+
+import android.content.Context
+import android.graphics.Bitmap
+import androidx.test.core.app.ApplicationProvider
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.work.ListenableWorker.Result.Failure
+import androidx.work.ListenableWorker.Result.Success
+import androidx.work.WorkerParameters
+import androidx.work.testing.TestWorkerBuilder
+import androidx.work.workDataOf
+import com.example.background.Constants
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import org.junit.runner.RunWith
+import java.lang.RuntimeException
+import java.util.concurrent.Executors.newSingleThreadExecutor
+
+@RunWith(AndroidJUnit4::class)
+class BaseFilterWorkerTest {
+
+    private lateinit var worker: TestBaseFilterWorker
+    private val context: Context = ApplicationProvider.getApplicationContext()
+
+    @Test
+    fun testFiltering_withExistingUri() {
+        val worker = TestWorkerBuilder<TestBaseFilterWorker>(
+            context,
+            newSingleThreadExecutor(),
+            workDataOf(Constants.KEY_IMAGE_URI to "file:///android_asset/watson.jpg")
+        ).build()
+
+        val result = worker.doWork()
+        assertTrue(result is Success)
+    }
+
+    @Test
+    fun testFiltering_invalidUri() {
+        worker = TestWorkerBuilder<TestBaseFilterWorker>(
+            context,
+            newSingleThreadExecutor(),
+            inputData = workDataOf(Constants.KEY_IMAGE_URI to "file:///android_asset/invalid")
+        ).build()
+
+        val result = worker.doWork()
+        assertTrue(result is Failure)
+    }
+
+    @Test(expected = IllegalArgumentException::class)
+    fun testFiltering_missingUri() {
+        worker = TestWorkerBuilder<TestBaseFilterWorker>(context, newSingleThreadExecutor()).build()
+        worker.doWork() // throws Exception
+    }
+}
+
+/** Implementation of [BaseFilterWorker] for tests. GNDN */
+class TestBaseFilterWorker(
+    context: Context,
+    workerParameters: WorkerParameters
+) : BaseFilterWorker(context, workerParameters) {
+    // Don't filter, just return the same bitmap
+    override fun applyFilter(input: Bitmap) = input
+}
\ No newline at end of file

WorkManagerSample/lib/src/main/java/com/example/background/workers/CleanupWorker.kt

@@ -18,6 +18,7 @@ package com.example.background.workers
 
 import android.content.Context
 import android.util.Log
+import androidx.annotation.VisibleForTesting
 import androidx.work.CoroutineWorker
 import androidx.work.WorkerParameters
 import com.example.background.Constants
@@ -29,6 +30,9 @@ import java.io.File
 class CleanupWorker(appContext: Context, workerParams: WorkerParameters) :
     CoroutineWorker(appContext, workerParams) {
 
+    @VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)
+    internal val targetDirectory = File(applicationContext.filesDir, Constants.OUTPUT_PATH)
+
     override suspend fun doWork(): Result {
         return withContext(Dispatchers.IO) {
             try {
@@ -43,7 +47,7 @@ class CleanupWorker(appContext: Context, workerParams: WorkerParameters) :
 
     /** Removes pngs from the app's files directory */
     private fun cleanupDirectory() {
-        File(applicationContext.filesDir, Constants.OUTPUT_PATH).apply {
+        targetDirectory.apply {
             if (exists()) {
                 listFiles()?.forEach { file ->
                     if (file.name.endsWith(".png")) {

WorkManagerSample/lib/src/main/java/com/example/background/workers/filters/BaseFilterWorker.kt

@@ -31,9 +31,9 @@ import android.util.Log
 import androidx.annotation.StringRes
 import androidx.annotation.VisibleForTesting
 import androidx.core.app.NotificationCompat.Builder
-import androidx.work.CoroutineWorker
 import androidx.work.ForegroundInfo
 import androidx.work.WorkManager
+import androidx.work.Worker
 import androidx.work.WorkerParameters
 import androidx.work.workDataOf
 import com.example.background.Constants
@@ -46,16 +46,16 @@ import java.io.InputStream
 import java.util.UUID
 
 abstract class BaseFilterWorker(context: Context, parameters: WorkerParameters) :
-    CoroutineWorker(context, parameters) {
+    Worker(context, parameters) {
 
     private val notificationManager =
         context.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
 
-    override suspend fun doWork(): Result {
+    override fun doWork(): Result {
         val resourceUri = inputData.getString(Constants.KEY_IMAGE_URI) ?:
         throw IllegalArgumentException("Invalid input uri")
         return try {
-            setForeground(createForegroundInfo())
+            setForegroundAsync(createForegroundInfo())
             val inputStream = inputStreamFor(applicationContext, resourceUri)
             val bitmap = BitmapFactory.decodeStream(inputStream)
             val output = applyFilter(bitmap)
@@ -64,7 +64,7 @@ abstract class BaseFilterWorker(context: Context, parameters: WorkerParameters)
             Result.success(workDataOf(Constants.KEY_IMAGE_URI to outputUri.toString()))
         } catch (fileNotFoundException: FileNotFoundException) {
             Log.e(TAG, "Failed to decode input stream", fileNotFoundException)
-            throw RuntimeException("Failed to decode input stream", fileNotFoundException)
+            Result.failure()
         } catch (throwable: Throwable) {
             Log.e(TAG, "Error applying filter", throwable)
             Result.failure()

WorkManagerSample/versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl

versions.gradle

@@ -27,10 +27,10 @@ versions.annotations = "1.0.0"
 versions.apache_commons = "2.5"
 versions.appcompat = "1.2.0-alpha02"
 versions.arch_core = "2.1.0"
-versions.atsl_core = "1.2.0"
-versions.atsl_junit = "1.1.1"
-versions.atsl_rules = "1.2.0"
-versions.atsl_runner = "1.2.0"
+versions.atsl_core = "1.3.0"
+versions.atsl_junit = "1.1.2"
+versions.atsl_rules = "1.3.0"
+versions.atsl_runner = "1.3.0"
 versions.benchmark = "1.1.0-alpha01"
 versions.cardview = "1.0.0"
 versions.constraint_layout = "2.0.0-alpha2"
@@ -92,6 +92,7 @@ deps.arch_core = arch_core
 def atsl = [:]
 atsl.core = "androidx.test:core:$versions.atsl_core"
 atsl.ext_junit = "androidx.test.ext:junit:$versions.atsl_junit"
+atsl.ext_junit_ktx = "androidx.test.ext:junit-ktx:$versions.atsl_junit"
 atsl.runner = "androidx.test:runner:$versions.atsl_runner"
 atsl.rules = "androidx.test:rules:$versions.atsl_rules"
 deps.atsl = atsl