Merge 931de6b302 into e846078f9d

core/datastore/src/main/kotlin/com/google/samples/apps/nowinandroid/core/datastore/NiaPreferencesDataSource.kt

@@ -21,6 +21,7 @@ import androidx.datastore.core.DataStore
 import com.google.samples.apps.nowinandroid.core.model.data.DarkThemeConfig
 import com.google.samples.apps.nowinandroid.core.model.data.ThemeBrand
 import com.google.samples.apps.nowinandroid.core.model.data.UserData
+import kotlinx.coroutines.flow.catch
 import kotlinx.coroutines.flow.firstOrNull
 import kotlinx.coroutines.flow.map
 import java.io.IOException
@@ -30,6 +31,14 @@ class NiaPreferencesDataSource @Inject constructor(
     private val userPreferences: DataStore<UserPreferences>,
 ) {
     val userData = userPreferences.data
+        .catch { exception ->
+            if (exception is IOException) {
+                Log.e("NiaPreferences", "Error reading user preferences.", exception)
+                emit(UserPreferences.getDefaultInstance())
+            } else {
+                throw exception
+            }
+        }
         .map {
             UserData(
                 bookmarkedNewsResources = it.bookmarkedNewsResourceIdsMap.keys,
@@ -155,6 +164,14 @@ class NiaPreferencesDataSource @Inject constructor(
     }
 
     suspend fun getChangeListVersions() = userPreferences.data
+        .catch { exception ->
+            if (exception is IOException) {
+                Log.e("NiaPreferences", "Error reading user preferences.", exception)
+                emit(UserPreferences.getDefaultInstance())
+            } else {
+                throw exception
+            }
+        }
         .map {
             ChangeListVersions(
                 topicVersion = it.topicChangeListVersion,

core/datastore/src/test/kotlin/com/google/samples/apps/nowinandroid/core/datastore/NiaPreferencesDataSourceTest.kt

@@ -16,15 +16,21 @@
 
 package com.google.samples.apps.nowinandroid.core.datastore
 
+import androidx.datastore.core.DataStore
+import androidx.datastore.core.IOException
 import com.google.samples.apps.nowinandroid.core.datastore.test.InMemoryDataStore
+import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.flow.flow
 import kotlinx.coroutines.test.TestScope
 import kotlinx.coroutines.test.UnconfinedTestDispatcher
 import kotlinx.coroutines.test.runTest
 import org.junit.Before
 import org.junit.Test
+import kotlin.test.assertEquals
 import kotlin.test.assertFalse
 import kotlin.test.assertTrue
+import kotlin.test.fail
 
 class NiaPreferencesDataSourceTest {
 
@@ -32,11 +38,30 @@ class NiaPreferencesDataSourceTest {
 
     private lateinit var subject: NiaPreferencesDataSource
 
+    // A DataStore implementation that throws an IOException when accessed
+    private val ioExceptionThrowingDataStore = object : DataStore<UserPreferences> {
+        override val data: Flow<UserPreferences>
+            get() = flow { throw IOException("Failed to read proto") }
+
+        override suspend fun updateData(transform: suspend (t: UserPreferences) -> UserPreferences): UserPreferences {
+            fail("Not needed for this test")
+        }
+    }
+
     @Before
     fun setup() {
         subject = NiaPreferencesDataSource(InMemoryDataStore(UserPreferences.getDefaultInstance()))
     }
 
+    @Test
+    fun userData_emitDefault_whenDataStoreThrowsIOException() =
+        testScope.runTest {
+            val dataSource = NiaPreferencesDataSource(ioExceptionThrowingDataStore)
+            val actualUserData = dataSource.userData.first()
+
+            assertEquals(subject.userData.first(), actualUserData)
+        }
+
     @Test
     fun shouldHideOnboardingIsFalseByDefault() = testScope.runTest {
         assertFalse(subject.userData.first().shouldHideOnboarding)
@@ -76,6 +101,15 @@ class NiaPreferencesDataSourceTest {
             assertFalse(subject.userData.first().shouldHideOnboarding)
         }
 
+    @Test
+    fun getChangeListVersions_returnsDefault_whenDataStoreThrowsIOException() =
+        testScope.runTest {
+            val dataSource = NiaPreferencesDataSource(ioExceptionThrowingDataStore)
+            val actualResult = dataSource.getChangeListVersions()
+
+            assertEquals(subject.getChangeListVersions(), actualResult)
+        }
+
     @Test
     fun shouldUseDynamicColorFalseByDefault() = testScope.runTest {
         assertFalse(subject.userData.first().useDynamicColor)