Adding unit tests for ViewModel

Author: mnaturel

vector/src/main/java/im/vector/app/features/roomprofile/polls/RoomPollsViewModel.kt

@@ -82,7 +82,6 @@ class RoomPollsViewModel @AssistedInject constructor(
                 .launchIn(viewModelScope)
     }
 
-    // TODO add unit tests
     override fun handle(action: RoomPollsAction) {
         when (action) {
             RoomPollsAction.LoadMorePolls -> handleLoadMore()

vector/src/test/java/im/vector/app/features/roomprofile/polls/RoomPollsViewModelTest.kt

@@ -17,21 +17,25 @@
 package im.vector.app.features.roomprofile.polls
 
 import com.airbnb.mvrx.test.MavericksTestRule
+import im.vector.app.features.roomprofile.polls.list.data.LoadedPollsStatus
 import im.vector.app.features.roomprofile.polls.list.domain.GetLoadedPollsStatusUseCase
-import im.vector.app.features.roomprofile.polls.list.ui.PollSummary
 import im.vector.app.features.roomprofile.polls.list.domain.GetPollsUseCase
 import im.vector.app.features.roomprofile.polls.list.domain.LoadMorePollsUseCase
 import im.vector.app.features.roomprofile.polls.list.domain.SyncPollsUseCase
+import im.vector.app.features.roomprofile.polls.list.ui.PollSummary
 import im.vector.app.test.test
 import im.vector.app.test.testDispatcher
+import io.mockk.coEvery
+import io.mockk.coJustRun
+import io.mockk.coVerify
 import io.mockk.every
 import io.mockk.mockk
 import io.mockk.verify
 import kotlinx.coroutines.flow.flowOf
 import org.junit.Rule
 import org.junit.Test
 
-private const val ROOM_ID = "room-id"
+private const val A_ROOM_ID = "room-id"
 
 class RoomPollsViewModelTest {
 
@@ -42,7 +46,7 @@ class RoomPollsViewModelTest {
     private val fakeGetLoadedPollsStatusUseCase = mockk<GetLoadedPollsStatusUseCase>()
     private val fakeLoadMorePollsUseCase = mockk<LoadMorePollsUseCase>()
     private val fakeSyncPollsUseCase = mockk<SyncPollsUseCase>()
-    private val initialState = RoomPollsViewState(ROOM_ID)
+    private val initialState = RoomPollsViewState(A_ROOM_ID)
 
     private fun createViewModel(): RoomPollsViewModel {
         return RoomPollsViewModel(
@@ -55,11 +59,17 @@ class RoomPollsViewModelTest {
     }
 
     @Test
-    fun `given viewModel when created then polls list is observed and viewState is updated`() {
+    fun `given viewModel when created then polls list is observed, sync is launched and viewState is updated`() {
         // Given
+        val loadedPollsStatus = givenGetLoadedPollsStatusSuccess()
+        givenSyncPollsWithSuccess()
         val polls = listOf(givenAPollSummary())
-        every { fakeGetPollsUseCase.execute(ROOM_ID) } returns flowOf(polls)
-        val expectedViewState = initialState.copy(polls = polls)
+        every { fakeGetPollsUseCase.execute(A_ROOM_ID) } returns flowOf(polls)
+        val expectedViewState = initialState.copy(
+                polls = polls,
+                canLoadMore = loadedPollsStatus.canLoadMore,
+                nbLoadedDays = loadedPollsStatus.nbLoadedDays,
+        )
 
         // When
         val viewModel = createViewModel()
@@ -70,11 +80,88 @@ class RoomPollsViewModelTest {
                 .assertLatestState(expectedViewState)
                 .finish()
         verify {
-            fakeGetPollsUseCase.execute(ROOM_ID)
+            fakeGetPollsUseCase.execute(A_ROOM_ID)
         }
+        coVerify { fakeSyncPollsUseCase.execute(A_ROOM_ID) }
+    }
+
+    @Test
+    fun `given viewModel and error during sync process when created then error is raised in view event`() {
+        // Given
+        givenGetLoadedPollsStatusSuccess()
+        givenSyncPollsWithError(Exception())
+        val polls = listOf(givenAPollSummary())
+        every { fakeGetPollsUseCase.execute(A_ROOM_ID) } returns flowOf(polls)
+
+        // When
+        val viewModel = createViewModel()
+        val viewModelTest = viewModel.test()
+
+        // Then
+        viewModelTest
+                .assertEvents(RoomPollsViewEvent.LoadingError)
+                .finish()
+        coVerify { fakeSyncPollsUseCase.execute(A_ROOM_ID) }
+    }
+
+    @Test
+    fun `given viewModel when handle load more action then viewState is updated`() {
+        // Given
+        val loadedPollsStatus = givenGetLoadedPollsStatusSuccess()
+        givenSyncPollsWithSuccess()
+        val polls = listOf(givenAPollSummary())
+        every { fakeGetPollsUseCase.execute(A_ROOM_ID) } returns flowOf(polls)
+        val newLoadedPollsStatus = givenLoadMoreWithSuccess()
+        val viewModel = createViewModel()
+        val stateAfterInit = initialState.copy(
+                polls = polls,
+                canLoadMore = loadedPollsStatus.canLoadMore,
+                nbLoadedDays = loadedPollsStatus.nbLoadedDays,
+        )
+
+        // When
+        val viewModelTest = viewModel.test()
+        viewModel.handle(RoomPollsAction.LoadMorePolls)
+
+        // Then
+        viewModelTest
+                .assertStatesChanges(
+                        stateAfterInit,
+                        { copy(isLoadingMore = true) },
+                        { copy(canLoadMore = newLoadedPollsStatus.canLoadMore, nbLoadedDays = newLoadedPollsStatus.nbLoadedDays) },
+                        { copy(isLoadingMore = false) },
+                )
+                .finish()
+        coVerify { fakeLoadMorePollsUseCase.execute(A_ROOM_ID) }
     }
 
     private fun givenAPollSummary(): PollSummary {
         return mockk()
     }
+
+    private fun givenSyncPollsWithSuccess() {
+        coJustRun { fakeSyncPollsUseCase.execute(A_ROOM_ID) }
+    }
+
+    private fun givenSyncPollsWithError(error: Exception) {
+        coEvery { fakeSyncPollsUseCase.execute(A_ROOM_ID) } throws error
+    }
+
+    private fun givenLoadMoreWithSuccess(): LoadedPollsStatus {
+        val loadedPollsStatus = givenALoadedPollsStatus(canLoadMore = false, nbLoadedDays = 20)
+        coEvery { fakeLoadMorePollsUseCase.execute(A_ROOM_ID) } returns loadedPollsStatus
+        return loadedPollsStatus
+    }
+
+    private fun givenGetLoadedPollsStatusSuccess(): LoadedPollsStatus {
+        val loadedPollsStatus = givenALoadedPollsStatus()
+        every { fakeGetLoadedPollsStatusUseCase.execute(A_ROOM_ID) } returns loadedPollsStatus
+        return loadedPollsStatus
+    }
+
+    private fun givenALoadedPollsStatus(canLoadMore: Boolean = true, nbLoadedDays: Int = 10) =
+            LoadedPollsStatus(
+                    canLoadMore = canLoadMore,
+                    nbLoadedDays = nbLoadedDays,
+            )
 }