Fixes flakiness in app's screenshot tests

.github/workflows/Build.yaml

@@ -128,6 +128,13 @@ jobs:
           name: local-test-results
           path: '**/build/test-results/test*UnitTest/**.xml'
 
+      - name: Upload screenshot results (PNG)
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: screenshot-test-results
+          path: '**/build/outputs/roborazzi/*_compare.png'
+
       - name: Check lint
         run: ./gradlew :app:lintProdRelease :app-nia-catalog:lintRelease :lint:lint
 

app/build.gradle.kts

@@ -113,6 +113,7 @@ dependencies {
 
     testImplementation(projects.core.dataTest)
     testImplementation(projects.core.testing)
+    testImplementation(projects.sync.syncTest)
     testImplementation(libs.androidx.compose.ui.test)
     testImplementation(libs.hilt.android.testing)
     testImplementation(libs.work.testing)

app/src/testDemo/kotlin/com/google/samples/apps/nowinandroid/ui/NiaAppScreenSizesScreenshotTests.kt

@@ -16,7 +16,6 @@
 
 package com.google.samples.apps.nowinandroid.ui
 
-import android.util.Log
 import androidx.compose.material3.windowsizeclass.ExperimentalMaterial3WindowSizeClassApi
 import androidx.compose.material3.windowsizeclass.WindowSizeClass
 import androidx.compose.runtime.CompositionLocalProvider
@@ -28,10 +27,6 @@ import androidx.compose.ui.test.onRoot
 import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.DpSize
 import androidx.compose.ui.unit.dp
-import androidx.test.platform.app.InstrumentationRegistry
-import androidx.work.Configuration
-import androidx.work.testing.SynchronousExecutor
-import androidx.work.testing.WorkManagerTestInitHelper
 import com.github.takahirom.roborazzi.captureRoboImage
 import com.google.samples.apps.nowinandroid.core.data.repository.TopicsRepository
 import com.google.samples.apps.nowinandroid.core.data.repository.UserDataRepository
@@ -109,17 +104,6 @@ class NiaAppScreenSizesScreenshotTests {
 
     @Before
     fun setup() {
-        val config = Configuration.Builder()
-            .setMinimumLoggingLevel(Log.DEBUG)
-            .setExecutor(SynchronousExecutor())
-            .build()
-
-        // Initialize WorkManager for instrumentation tests.
-        WorkManagerTestInitHelper.initializeTestWorkManager(
-            InstrumentationRegistry.getInstrumentation().context,
-            config,
-        )
-
         hiltRule.inject()
 
         // Configure user data

app/src/testDemo/kotlin/com/google/samples/apps/nowinandroid/ui/SnackbarScreenshotTests.kt

@@ -16,24 +16,21 @@
 
 package com.google.samples.apps.nowinandroid.ui
 
-import android.util.Log
 import androidx.compose.foundation.layout.BoxWithConstraints
 import androidx.compose.material3.SnackbarDuration.Indefinite
 import androidx.compose.material3.SnackbarHostState
 import androidx.compose.material3.windowsizeclass.ExperimentalMaterial3WindowSizeClassApi
 import androidx.compose.material3.windowsizeclass.WindowSizeClass
+import androidx.compose.runtime.CompositionLocalProvider
 import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.ui.platform.LocalInspectionMode
 import androidx.compose.ui.test.DeviceConfigurationOverride
 import androidx.compose.ui.test.ForcedSize
 import androidx.compose.ui.test.junit4.createAndroidComposeRule
 import androidx.compose.ui.test.onRoot
 import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.DpSize
 import androidx.compose.ui.unit.dp
-import androidx.test.platform.app.InstrumentationRegistry
-import androidx.work.Configuration
-import androidx.work.testing.SynchronousExecutor
-import androidx.work.testing.WorkManagerTestInitHelper
 import com.github.takahirom.roborazzi.captureRoboImage
 import com.google.samples.apps.nowinandroid.core.data.repository.TopicsRepository
 import com.google.samples.apps.nowinandroid.core.data.repository.UserNewsResourceRepository
@@ -60,6 +57,7 @@ import org.robolectric.RobolectricTestRunner
 import org.robolectric.annotation.Config
 import org.robolectric.annotation.GraphicsMode
 import org.robolectric.annotation.LooperMode
+import java.util.TimeZone
 import javax.inject.Inject
 
 /**
@@ -112,17 +110,6 @@ class SnackbarScreenshotTests {
 
     @Before
     fun setup() {
-        val config = Configuration.Builder()
-            .setMinimumLoggingLevel(Log.DEBUG)
-            .setExecutor(SynchronousExecutor())
-            .build()
-
-        // Initialize WorkManager for instrumentation tests.
-        WorkManagerTestInitHelper.initializeTestWorkManager(
-            InstrumentationRegistry.getInstrumentation().context,
-            config,
-        )
-
         hiltRule.inject()
 
         // Configure user data
@@ -135,6 +122,12 @@ class SnackbarScreenshotTests {
         }
     }
 
+    @Before
+    fun setTimeZone() {
+        // Make time zone deterministic in tests
+        TimeZone.setDefault(TimeZone.getTimeZone("UTC"))
+    }
+
     @Test
     fun phone_noSnackbar() {
         val snackbarHostState = SnackbarHostState()
@@ -207,22 +200,27 @@ class SnackbarScreenshotTests {
     ) {
         lateinit var scope: CoroutineScope
         composeTestRule.setContent {
-            scope = rememberCoroutineScope()
-
-            DeviceConfigurationOverride(
-                DeviceConfigurationOverride.ForcedSize(DpSize(width, height)),
+            CompositionLocalProvider(
+                // Replaces images with placeholders
+                LocalInspectionMode provides true,
             ) {
-                BoxWithConstraints {
-                    val appState = rememberNiaAppState(
-                        windowSizeClass = WindowSizeClass.calculateFromSize(
-                            DpSize(maxWidth, maxHeight),
-                        ),
-                        networkMonitor = networkMonitor,
-                        userNewsResourceRepository = userNewsResourceRepository,
-                        timeZoneMonitor = timeZoneMonitor,
-                    )
-                    NiaTheme {
-                        NiaApp(appState, snackbarHostState, false, {}, {})
+                scope = rememberCoroutineScope()
+
+                DeviceConfigurationOverride(
+                    DeviceConfigurationOverride.ForcedSize(DpSize(width, height)),
+                ) {
+                    BoxWithConstraints {
+                        val appState = rememberNiaAppState(
+                            windowSizeClass = WindowSizeClass.calculateFromSize(
+                                DpSize(maxWidth, maxHeight),
+                            ),
+                            networkMonitor = networkMonitor,
+                            userNewsResourceRepository = userNewsResourceRepository,
+                            timeZoneMonitor = timeZoneMonitor,
+                        )
+                        NiaTheme {
+                            NiaApp(appState, snackbarHostState, false, {}, {})
+                        }
                     }
                 }
             }

sync/sync-test/src/main/kotlin/com/google/samples/apps/nowinandroid/core/sync/test/TestSyncModule.kt

@@ -18,6 +18,8 @@ package com.google.samples.apps.nowinandroid.core.sync.test
 
 import com.google.samples.apps.nowinandroid.core.data.util.SyncManager
 import com.google.samples.apps.nowinandroid.sync.di.SyncModule
+import com.google.samples.apps.nowinandroid.sync.status.StubSyncSubscriber
+import com.google.samples.apps.nowinandroid.sync.status.SyncSubscriber
 import dagger.Binds
 import dagger.Module
 import dagger.hilt.components.SingletonComponent
@@ -33,4 +35,9 @@ internal interface TestSyncModule {
     fun bindsSyncStatusMonitor(
         syncStatusMonitor: NeverSyncingSyncManager,
     ): SyncManager
+
+    @Binds
+    fun bindsSyncSubscriber(
+        syncSubscriber: StubSyncSubscriber,
+    ): SyncSubscriber
 }

sync/work/src/main/kotlin/com/google/samples/apps/nowinandroid/sync/status/StubSyncSubscriber.kt

@@ -24,7 +24,7 @@ private const val TAG = "StubSyncSubscriber"
 /**
  * Stub implementation of [SyncSubscriber]
  */
-internal class StubSyncSubscriber @Inject constructor() : SyncSubscriber {
+class StubSyncSubscriber @Inject constructor() : SyncSubscriber {
     override suspend fun subscribe() {
         Log.d(TAG, "Subscribing to sync")
     }