removes use of LiveData in EditCategoriesViewModel.kt, adds (flaky) u…

…nit tests
willowtreeapps · Jun 17, 2024 · b175bd5 · b175bd5
1 parent f8efd1c
commit b175bd5
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Showing 3 changed files with 34 additions and 84 deletions.
diff --git a/app/src/androidTest/java/com/willowtree/vocable/settings/EditCategoriesViewModelTest.kt b/app/src/androidTest/java/com/willowtree/vocable/settings/EditCategoriesViewModelTest.kt
@@ -1,7 +1,5 @@
 package com.willowtree.vocable.settings
 
-import androidx.arch.core.executor.testing.InstantTaskExecutorRule
-import androidx.lifecycle.Observer
 import androidx.room.Room
 import androidx.test.core.app.ApplicationProvider
 import app.cash.turbine.test
@@ -20,13 +18,7 @@ import com.willowtree.vocable.room.VocableDatabase
 import com.willowtree.vocable.utility.FakeDateProvider
 import com.willowtree.vocable.utility.StubLegacyCategoriesAndPhrasesRepository
 import com.willowtree.vocable.utility.VocableKoinTestRule
-import junit.framework.TestCase
-import kotlinx.coroutines.ExperimentalCoroutinesApi
-import kotlinx.coroutines.flow.first
-import kotlinx.coroutines.test.UnconfinedTestDispatcher
 import kotlinx.coroutines.test.runTest
-import kotlinx.coroutines.launch
-import kotlinx.coroutines.test.advanceUntilIdle
 import org.junit.Assert.assertEquals
 import org.junit.Rule
 import org.junit.Test
@@ -39,9 +31,6 @@ class EditCategoriesViewModelTest {
     @get:Rule
     val mainDispatcherRule = MainDispatcherRule()
 
-    @get:Rule
-    val instantExecutorRule = InstantTaskExecutorRule()
-
     private val database = Room.inMemoryDatabaseBuilder(
         ApplicationProvider.getApplicationContext(),
         VocableDatabase::class.java
@@ -85,81 +74,54 @@ class EditCategoriesViewModelTest {
         )
     }
 
-    // 1. refreshing categories without adding new category remains at first index
-    // 2. adding new category and refreshing once flips to new category's index
-    // 3. adding new category and refreshing twice flips to first index
-    // 4. adding new category amongst hidden categories and refreshing once flips to new category's index (before hidden categories)
-
-    @OptIn(ExperimentalCoroutinesApi::class)
+    // TODO: CC - the following 4 tests are flaky due to the way refreshCategories() is implemented
     @Test
-    fun  refreshing_categories_without_adding_new_category_remains_at_first_index() = runTest(UnconfinedTestDispatcher()) {
+    fun  refreshing_categories_without_adding_new_category_remains_at_first_index() = runTest {
         val vm = createViewModel()
         vm.refreshCategories()
 
-        var index: Int? = null
-        val observer = Observer<Int> { value ->
-            index = value
-        }
-
-        try {
-            vm.lastViewedIndex.observeForever(observer)
-            advanceUntilIdle()
-            assertEquals(0, index)
-        } finally {
-            vm.lastViewedIndex.removeObserver(observer)
+        vm.liveLastViewedIndex.test {
+            assertEquals(0, awaitItem())
         }
     }
 
-    @OptIn(ExperimentalCoroutinesApi::class)
     @Test
-    fun  adding_new_category_and_refreshing_once_flips_to_new_categorys_index() = runTest(UnconfinedTestDispatcher()) {
+    fun  adding_new_category_and_refreshing_once_flips_to_new_categorys_index() = runTest {
+
         val vm = createViewModel()
         vm.refreshCategories()
 
         categoriesUseCase.addCategory("new category")
         vm.refreshCategories()
 
-        var index: Int? = null
-        val observer = Observer<Int> { value ->
-            index = value
-        }
-
-        try {
-            vm.lastViewedIndex.observeForever(observer)
-            advanceUntilIdle()
-            assertEquals(7, index)
-        } finally {
-            vm.lastViewedIndex.removeObserver(observer)
+        vm.liveLastViewedIndex.test {
+            assertEquals(0, awaitItem())
+            assertEquals(7, awaitItem())
         }
     }
 
-    @OptIn(ExperimentalCoroutinesApi::class)
     @Test
-    fun  adding_new_category_and_refreshing_twice_flips_to_first_index() = runTest(UnconfinedTestDispatcher()) {
+    fun  adding_new_category_and_refreshing_twice_flips_to_first_index() = runTest {
         val vm = createViewModel()
         vm.refreshCategories()
 
         categoriesUseCase.addCategory("new category")
-        vm.refreshCategories()
-        vm.refreshCategories()
 
-        var index: Int? = null
-        val observer = Observer<Int> { value ->
-            index = value
+        vm.refreshCategories()
+        vm.liveLastViewedIndex.test {
+            assertEquals(0, awaitItem())
+            assertEquals(7, awaitItem())
         }
 
-        try {
-            vm.lastViewedIndex.observeForever(observer)
-            advanceUntilIdle()
-            assertEquals(0, index)
-        } finally {
-            vm.lastViewedIndex.removeObserver(observer)
+        vm.refreshCategories()
+        vm.liveLastViewedIndex.test {
+            assertEquals(7, awaitItem())
+            assertEquals(0, awaitItem())
         }
     }
 
-    @OptIn(ExperimentalCoroutinesApi::class)
     @Test
-    fun  adding_new_category_amongst_hidden_categories_and_refreshing_once_flips_to_last_non_hidden_index() = runTest(UnconfinedTestDispatcher()) {
+    fun  adding_new_category_amongst_hidden_categories_and_refreshing_once_flips_to_last_non_hidden_index() = runTest {
         val vm = createViewModel()
         categoriesUseCase.updateCategoryHidden("preset_general", hidden = true)
         categoriesUseCase.updateCategoryHidden("preset_basic_needs", hidden = true)
@@ -168,22 +130,12 @@ class EditCategoriesViewModelTest {
 
         categoriesUseCase.addCategory("new category")
 
-        categoriesUseCase.categories().first()
-
         vm.refreshCategories()
-
-        var index: Int? = null
-        val observer = Observer<Int> { value ->
-            index = value
+        vm.liveLastViewedIndex.test {
+            assertEquals(0, awaitItem())
+            assertEquals(5, awaitItem())
         }
 
-        try {
-            vm.lastViewedIndex.observeForever(observer)
-            advanceUntilIdle()
-            assertEquals(5, index)
-        } finally {
-            vm.lastViewedIndex.removeObserver(observer)
-        }
     }
 
     @Test

diff --git a/app/src/main/java/com/willowtree/vocable/settings/EditCategoriesFragment.kt b/app/src/main/java/com/willowtree/vocable/settings/EditCategoriesFragment.kt
@@ -7,6 +7,7 @@ import androidx.fragment.app.FragmentManager
 import androidx.lifecycle.Lifecycle
 import androidx.lifecycle.lifecycleScope
 import androidx.lifecycle.repeatOnLifecycle
+import androidx.lifecycle.viewModelScope
 import androidx.navigation.fragment.findNavController
 import androidx.viewpager2.widget.ViewPager2
 import com.willowtree.vocable.BaseFragment
@@ -16,6 +17,7 @@ import com.willowtree.vocable.R
 import com.willowtree.vocable.databinding.FragmentEditCategoriesBinding
 import com.willowtree.vocable.presets.Category
 import com.willowtree.vocable.utils.VocableFragmentStateAdapter
+import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.launch
 import org.koin.androidx.viewmodel.ViewModelOwner
 import org.koin.androidx.viewmodel.ext.android.viewModel
@@ -121,15 +123,12 @@ class EditCategoriesFragment : BaseFragment<FragmentEditCategoriesBinding>() {
             }
         }
 
-        editCategoriesViewModel.lastViewedIndex.observe(viewLifecycleOwner) {
-            it?.let { index ->
-                val pageNum = index / maxEditCategories
-                // Wait until view pager has finished its layout
-                binding.editCategoriesViewPager.post {
+        editCategoriesViewModel.viewModelScope.launch {
+            editCategoriesViewModel.liveLastViewedIndex.collect {
+                val pageNum = it/maxEditCategories
                     if (isAdded && binding.editCategoriesViewPager.currentItem != pageNum) {
                         binding.editCategoriesViewPager.setCurrentItem(pageNum, false)
                     }
-                }
             }
         }
     }

diff --git a/app/src/main/java/com/willowtree/vocable/settings/EditCategoriesViewModel.kt b/app/src/main/java/com/willowtree/vocable/settings/EditCategoriesViewModel.kt
@@ -1,12 +1,12 @@
 package com.willowtree.vocable.settings
 
-import androidx.lifecycle.LiveData
-import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import com.willowtree.vocable.ICategoriesUseCase
 import com.willowtree.vocable.presets.Category
+import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
 
 class EditCategoriesViewModel(
@@ -15,8 +15,7 @@ class EditCategoriesViewModel(
 
     val categoryList = categoriesUseCase.categories()
 
-    private val liveLastViewedIndex = MutableLiveData<Int>()
-    val lastViewedIndex: LiveData<Int> = liveLastViewedIndex
+    val liveLastViewedIndex =  MutableStateFlow(0)
 
     private var overallCategories = listOf<Category>()
 
@@ -31,20 +30,20 @@ class EditCategoriesViewModel(
             if (oldCategories.isNotEmpty() && oldCategories.size < overallCategories.size) {
                 when (val firstHiddenIndex = overallCategories.indexOfFirst { it.hidden }) {
                     -1 -> {
-                        liveLastViewedIndex.postValue(overallCategories.size - 1)
+                        liveLastViewedIndex.update { overallCategories.size - 1 }
                     }
 
                     0 -> {
-                        liveLastViewedIndex.postValue(0)
+                        liveLastViewedIndex.update { 0 }
                     }
 
                     else -> {
-                        liveLastViewedIndex.postValue(firstHiddenIndex - 1)
+                        liveLastViewedIndex.update { firstHiddenIndex - 1 }
                     }
                 }
             }
             else {
-                liveLastViewedIndex.postValue(0)
+                liveLastViewedIndex.update { 0 }
             }
         }
     }