Add Robolectric to allow ViewModel tests to pass

Change-Id: I782fab167103edbdaa1d95839b4fbc6e659fef4e

feature/interests/build.gradle.kts

@@ -28,6 +28,7 @@ dependencies {
     implementation(projects.core.domain)
 
     testImplementation(projects.core.testing)
+    testImplementation(libs.robolectric)
 
     androidTestImplementation(projects.core.testing)
 }

feature/interests/src/test/kotlin/com/google/samples/apps/nowinandroid/interests/InterestsViewModelTest.kt

@@ -34,12 +34,21 @@ import kotlinx.coroutines.test.runTest
 import org.junit.Before
 import org.junit.Rule
 import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.RobolectricTestRunner
 import kotlin.test.assertEquals
 
 /**
  * To learn more about how this test handles Flows created with stateIn, see
  * https://developer.android.com/kotlin/flow/test#statein
+ *
+ * These tests use Robolectric because the subject under test (the ViewModel) uses
+ * `SavedStateHandle.toRoute` which has a dependency on `android.os.Bundle`.
+ *
+ * TODO: Remove Robolectric if/when AndroidX Navigation API is updated to remove Android dependency.
+ *  See b/340966212.
  */
+@RunWith(RobolectricTestRunner::class)
 class InterestsViewModelTest {
 
     @get:Rule
@@ -56,8 +65,6 @@ class InterestsViewModelTest {
     @Before
     fun setup() {
         viewModel = InterestsViewModel(
-            // TODO: This line causes tests to fail since it introduces an Android dependency
-            //  see b/340966212 for more information
             savedStateHandle = SavedStateHandle(
                 route = InterestsRoute(initialTopicId = testInputTopics[0].topic.id),
             ),

feature/topic/build.gradle.kts

@@ -28,6 +28,7 @@ dependencies {
     implementation(projects.core.data)
 
     testImplementation(projects.core.testing)
+    testImplementation(libs.robolectric)
 
     androidTestImplementation(projects.core.testing)
 }

feature/topic/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/topic/TopicViewModelTest.kt

@@ -17,6 +17,7 @@
 package com.google.samples.apps.nowinandroid.feature.topic
 
 import androidx.lifecycle.SavedStateHandle
+import androidx.navigation.testing.invoke
 import com.google.samples.apps.nowinandroid.core.data.repository.CompositeUserNewsResourceRepository
 import com.google.samples.apps.nowinandroid.core.model.data.FollowableTopic
 import com.google.samples.apps.nowinandroid.core.model.data.NewsResource
@@ -25,6 +26,7 @@ import com.google.samples.apps.nowinandroid.core.testing.repository.TestNewsRepo
 import com.google.samples.apps.nowinandroid.core.testing.repository.TestTopicsRepository
 import com.google.samples.apps.nowinandroid.core.testing.repository.TestUserDataRepository
 import com.google.samples.apps.nowinandroid.core.testing.util.MainDispatcherRule
+import com.google.samples.apps.nowinandroid.feature.topic.navigation.TopicRoute
 import kotlinx.coroutines.flow.collect
 import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.flow.first
@@ -35,13 +37,22 @@ import kotlinx.datetime.Instant
 import org.junit.Before
 import org.junit.Rule
 import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.RobolectricTestRunner
 import kotlin.test.assertEquals
 import kotlin.test.assertIs
 
 /**
  * To learn more about how this test handles Flows created with stateIn, see
  * https://developer.android.com/kotlin/flow/test#statein
+ *
+ * These tests use Robolectric because the subject under test (the ViewModel) uses
+ * `SavedStateHandle.toRoute` which has a dependency on `android.os.Bundle`.
+ *
+ * TODO: Remove Robolectric if/when AndroidX Navigation API is updated to remove Android dependency.
+ *  *  See b/340966212.
  */
+@RunWith(RobolectricTestRunner::class)
 class TopicViewModelTest {
 
     @get:Rule
@@ -59,8 +70,9 @@ class TopicViewModelTest {
     @Before
     fun setup() {
         viewModel = TopicViewModel(
-            // TODO: Figure out how to supply the correct dependency TopicDestination(id = testInputTopics[0].topic.id)
-            savedStateHandle = SavedStateHandle(mapOf("id" to testInputTopics[0].topic.id)),
+            savedStateHandle = SavedStateHandle(
+                route = TopicRoute(id = testInputTopics[0].topic.id),
+            ),
             userDataRepository = userDataRepository,
             topicsRepository = topicsRepository,
             userNewsResourceRepository = userNewsResourceRepository,