Merge pull request #1182 from kiwix/macgills/#1174-introduce-unit-testing

Macgills/#1174 introduce unit testing

README.md

@@ -24,12 +24,12 @@ We utilize different build variants (flavours) to build various different versio
 - [Retrofit](http://square.github.io/retrofit/) - Retrofit turns your REST API into a Java interface
 - [OkHttp](https://github.com/square/okhttp) - An HTTP+SPDY client for Android and Java applications
 - [Butterknife](http://jakewharton.github.io/butterknife/) - View "injection" library for Android
-- [Mockito](https://github.com/mockito/mockito) - Most popular Mocking framework for unit tests written in Java 
+- [Mockito](https://github.com/mockito/mockito) - Most popular Mocking framework for unit tests written in Java
-- [Guava](https://github.com/google/guava) - Collections, caching, primitives support, concurrency libraries, common annotations, string processing, I/O, and so forth.
-- [Apache](https://github.com/apache/commons-io) - The Apache Commons IO library contains utility classes, stream implementations, file filters, file comparators, endian transformation classes, and much more.
 - [RxJava](https://github.com/ReactiveX/RxJava) - Reactive Extensions for the JVM – a library for composing asynchronous and event-based programs using observable sequences for the Java VM.
-
+- [ObjectBox] (https://github.com/objectbox/objectbox-java) - Reactive NoSQL Databse to replace SquiDb
-
+- [MockK] (https://github.com/mockk/mockk) - Kotlin mocking library that allows mocking of final classes by default.
+- [JUnit5] (https://github.com/junit-team/junit5/) - The next generation of JUnit
+- [AssertJ] (https://github.com/joel-costigliola/assertj-core) - Fluent assertions for test code
 
 ## Contributing
 

app/build.gradle

@@ -110,11 +110,9 @@ dependencies {
   implementation "io.reactivex.rxjava2:rxjava:$rxJavaVersion"
 
   // JUnit
-  testImplementation 'junit:junit:4.12'
   androidTestImplementation 'junit:junit:4.12'
 
   // Mockito
-  testImplementation "org.mockito:mockito-core:2.24.5"
   androidTestImplementation "org.mockito:mockito-android:2.24.5"
 
   // Leak canary
@@ -136,6 +134,14 @@ dependencies {
   implementation "android.arch.lifecycle:extensions:1.1.1"
   implementation "io.objectbox:objectbox-kotlin:$objectboxVersion"
   implementation "io.objectbox:objectbox-rxjava:$objectboxVersion"
+
+  testImplementation "org.junit.jupiter:junit-jupiter:5.4.2"
+  testImplementation "io.mockk:mockk:1.9"
+  testImplementation "org.assertj:assertj-core:3.11.1"
+  //update this with androidx
+  testImplementation 'com.jraska.livedata:testing-ktx:0.2.1'
+  testImplementation 'android.arch.core:core-testing:1.1.1'
+
 }
 
 // Set custom app import directory
@@ -364,6 +370,9 @@ android {
   androidExtensions {
     experimental = true
   }
+  testOptions {
+    unitTests.returnDefaultValues = true
+  }
 }
 
 // Testdroid deployment configuration

app/src/main/java/org/kiwix/kiwixmobile/di/modules/ApplicationModule.java

@@ -25,6 +25,7 @@ import dagger.Module;
 import dagger.Provides;
 import dagger.android.AndroidInjectionModule;
 import javax.inject.Singleton;
+import org.kiwix.kiwixmobile.downloader.model.UriToFileConverter;
 import org.kiwix.kiwixmobile.utils.BookUtils;
 
 @Module(includes = {
@@ -52,4 +53,9 @@ public class ApplicationModule {
   BookUtils provideBookUtils() {
     return new BookUtils();
   }
+
+  @Provides @Singleton
+  UriToFileConverter provideUriToFIleCOnverter() {
+    return new UriToFileConverter.Impl();
+  }
 }

app/src/main/java/org/kiwix/kiwixmobile/downloader/model/BookOnDisk.kt

@@ -6,8 +6,8 @@ import java.io.File
 
 data class BookOnDisk(
   val databaseId: Long? = null,
-  val book: Book,
+  val book: Book = Book().apply { id = "" },
-  val file: File
+  val file: File = File("")
 ) {
   constructor(bookOnDiskEntity: BookOnDiskEntity) : this(
       bookOnDiskEntity.id,

app/src/main/java/org/kiwix/kiwixmobile/downloader/model/DownloadModel.kt

@@ -17,12 +17,11 @@
  */
 package org.kiwix.kiwixmobile.downloader.model
 
-import android.view.WindowId
-import org.kiwix.kiwixmobile.database.newdb.entities.DownloadEntity
 import org.kiwix.kiwixmobile.library.entity.LibraryNetworkEntity
+import org.kiwix.kiwixmobile.library.entity.LibraryNetworkEntity.Book
 
 data class DownloadModel(
   val databaseId: Long? = null,
-  val downloadId: Long,
+  val downloadId: Long = 0,
-  val book: LibraryNetworkEntity.Book
+  val book: LibraryNetworkEntity.Book = Book().apply { id = "" }
 )

app/src/main/java/org/kiwix/kiwixmobile/downloader/model/DownloadStatus.kt

@@ -55,21 +55,22 @@ import org.kiwix.kiwixmobile.library.entity.LibraryNetworkEntity.Book
 import java.io.File
 
 class DownloadStatus(
-  val downloadId: Long,
+  val downloadId: Long = 0L,
-  val title: String,
+  val title: String = "",
-  val description: String,
+  val description: String = "",
-  val state: DownloadState,
+  val state: DownloadState = DownloadState.Pending,
-  val bytesDownloadedSoFar: Long,
+  val bytesDownloadedSoFar: Long = 0,
-  val totalSizeBytes: Long,
+  val totalSizeBytes: Long = 0,
-  val lastModified: String,
+  val lastModified: String = "",
-  val localUri: String?,
+  val localUri: String? = null,
-  val mediaProviderUri: String?,
+  val mediaProviderUri: String? = null,
-  val mediaType: String?,
+  val mediaType: String? = null,
-  val uri: String?,
+  val uri: String? = null,
-  val book: Book
+  val book: Book = Book().apply { id = "" }
 ) {
 
-  fun toBookOnDisk() = BookOnDisk(book = book, file = File(Uri.parse(localUri).path))
+  fun toBookOnDisk(uriToFileConverter:UriToFileConverter) =
+    BookOnDisk(book = book, file = uriToFileConverter.convert(localUri))
 
   constructor(
     cursor: Cursor,
@@ -90,6 +91,11 @@ class DownloadStatus(
   )
 }
 
+interface UriToFileConverter {
+  fun convert(uriString: String?) = File(Uri.parse(uriString).path)
+  class Impl:UriToFileConverter{}
+}
+
 sealed class DownloadState(val stringId: Int) {
   companion object {
     fun from(

app/src/main/java/org/kiwix/kiwixmobile/zim_manager/ConnectivityBroadcastReceiver.kt

@@ -3,8 +3,8 @@ package org.kiwix.kiwixmobile.zim_manager
 import android.content.Context
 import android.content.Intent
 import android.net.ConnectivityManager
+import io.reactivex.Flowable
 import io.reactivex.processors.BehaviorProcessor
-import io.reactivex.processors.PublishProcessor
 import org.kiwix.kiwixmobile.extensions.networkState
 import javax.inject.Inject
 
@@ -13,14 +13,14 @@ class ConnectivityBroadcastReceiver @Inject constructor(private val connectivity
 
   override val action: String = ConnectivityManager.CONNECTIVITY_ACTION
 
-  val networkStates =
+  private val _networkStates = BehaviorProcessor.createDefault(connectivityManager.networkState)
-    BehaviorProcessor.createDefault(connectivityManager.networkState)
+  val networkStates: Flowable<NetworkState> = _networkStates
 
   override fun onIntentWithActionReceived(
     context: Context,
     intent: Intent
   ) {
-    networkStates.onNext(connectivityManager.networkState)
+    _networkStates.onNext(connectivityManager.networkState)
   }
 
 }

app/src/main/java/org/kiwix/kiwixmobile/zim_manager/DefaultLanguageProvider.kt

@@ -0,0 +1,13 @@
+package org.kiwix.kiwixmobile.zim_manager
+
+import android.content.Context
+import org.kiwix.kiwixmobile.zim_manager.library_view.adapter.Language
+import javax.inject.Inject
+
+class DefaultLanguageProvider @Inject constructor(private val context: Context) {
+  fun provide() = Language(
+      context.resources.configuration.locale.isO3Language,
+      true,
+      1
+  )
+}

app/src/main/java/org/kiwix/kiwixmobile/zim_manager/ZimManageViewModel.kt

@@ -21,6 +21,7 @@ package org.kiwix.kiwixmobile.zim_manager
 import android.app.Application
 import android.arch.lifecycle.MutableLiveData
 import android.arch.lifecycle.ViewModel
+import android.support.annotation.VisibleForTesting
 import io.reactivex.Flowable
 import io.reactivex.disposables.CompositeDisposable
 import io.reactivex.disposables.Disposable
@@ -39,6 +40,7 @@ import org.kiwix.kiwixmobile.downloader.model.DownloadItem
 import org.kiwix.kiwixmobile.downloader.model.DownloadModel
 import org.kiwix.kiwixmobile.downloader.model.DownloadState.Successful
 import org.kiwix.kiwixmobile.downloader.model.DownloadStatus
+import org.kiwix.kiwixmobile.downloader.model.UriToFileConverter
 import org.kiwix.kiwixmobile.extensions.calculateSearchMatches
 import org.kiwix.kiwixmobile.extensions.registerReceiver
 import org.kiwix.kiwixmobile.library.entity.LibraryNetworkEntity
@@ -71,7 +73,9 @@ class ZimManageViewModel @Inject constructor(
   private val context: Application,
   private val connectivityBroadcastReceiver: ConnectivityBroadcastReceiver,
   private val bookUtils: BookUtils,
-  private val fat32Checker: Fat32Checker
+  private val fat32Checker: Fat32Checker,
+  private val uriToFileConverter: UriToFileConverter,
+  private val defaultLanguageProvider: DefaultLanguageProvider
 ) : ViewModel() {
 
   val libraryItems: MutableLiveData<List<LibraryListItem>> = MutableLiveData()
@@ -94,6 +98,11 @@ class ZimManageViewModel @Inject constructor(
     context.registerReceiver(connectivityBroadcastReceiver)
   }
 
+  @VisibleForTesting
+  fun onClearedExposed() {
+    onCleared()
+  }
+
   override fun onCleared() {
     compositeDisposable.clear()
     context.unregisterReceiver(connectivityBroadcastReceiver)
@@ -105,16 +114,17 @@ class ZimManageViewModel @Inject constructor(
     val downloadStatuses = downloadStatuses(downloads)
     val booksFromDao = books()
     val networkLibrary = PublishProcessor.create<LibraryNetworkEntity>()
+    val languages = languageDao.languages()
     return arrayOf(
         updateDownloadItems(downloadStatuses),
         removeCompletedDownloadsFromDb(downloadStatuses),
         removeNonExistingDownloadsFromDb(downloadStatuses, downloads),
         updateBookItems(booksFromDao),
         checkFileSystemForBooksOnRequest(booksFromDao),
-        updateLibraryItems(booksFromDao, downloads, networkLibrary),
+        updateLibraryItems(booksFromDao, downloads, networkLibrary, languages),
-        updateLanguagesInDao(networkLibrary),
+        updateLanguagesInDao(networkLibrary, languages),
         updateNetworkStates(),
-        updateLanguageItemsForDialog(),
+        updateLanguageItemsForDialog(languages),
         requestsAndConnectivtyChangesToLibraryRequests(networkLibrary)
     )
   }
@@ -155,6 +165,7 @@ class ZimManageViewModel @Inject constructor(
       )
       .buffer(3, SECONDS)
       .map(this::downloadIdsWithNoStatusesOverBufferPeriod)
+      .filter { it.isNotEmpty() }
       .subscribe(
           {
             downloadDao.delete(*it.toLongArray())
@@ -184,13 +195,15 @@ class ZimManageViewModel @Inject constructor(
     )
   }
 
-  private fun updateLanguageItemsForDialog() = requestLanguagesDialog
+  private fun updateLanguageItemsForDialog(languages: Flowable<List<Language>>) =
-      .withLatestFrom(languageDao.languages(),
+    requestLanguagesDialog
-          BiFunction<Unit, List<Language>, List<Language>> { _, languages -> languages })
+        .withLatestFrom(
-      .subscribe(
+            languages,
-          languageItems::postValue,
+            BiFunction<Unit, List<Language>, List<Language>> { _, languages -> languages })
-          Throwable::printStackTrace
+        .subscribe(
-      )
+            languageItems::postValue,
+            Throwable::printStackTrace
+        )
 
   private fun updateNetworkStates() =
     connectivityBroadcastReceiver.networkStates.subscribe(
@@ -200,11 +213,12 @@ class ZimManageViewModel @Inject constructor(
   private fun updateLibraryItems(
     booksFromDao: Flowable<List<BookOnDisk>>,
     downloads: Flowable<List<DownloadModel>>,
-    library: Flowable<LibraryNetworkEntity>
+    library: Flowable<LibraryNetworkEntity>,
+    languages: Flowable<List<Language>>
   ) = Flowable.combineLatest(
       booksFromDao,
       downloads,
-      languageDao.languages().filter { it.isNotEmpty() },
+      languages.filter { it.isNotEmpty() },
       library,
       requestFiltering
           .doOnNext { libraryListIsRefreshing.postValue(true) }
@@ -221,15 +235,17 @@ class ZimManageViewModel @Inject constructor(
       )
 
   private fun updateLanguagesInDao(
-    library: Flowable<LibraryNetworkEntity>
+    library: Flowable<LibraryNetworkEntity>,
+    languages: Flowable<List<Language>>
   ) = library
       .subscribeOn(Schedulers.io())
       .map { it.books }
       .withLatestFrom(
-          languageDao.languages(),
+          languages,
           BiFunction(this::combineToLanguageList)
       )
       .map { it.sortedBy(Language::language) }
+      .filter { it.isNotEmpty() }
       .subscribe(
           languageDao::insert,
           Throwable::printStackTrace
@@ -278,11 +294,7 @@ class ZimManageViewModel @Inject constructor(
 
   private fun defaultLanguage() =
     listOf(
-        Language(
+        defaultLanguageProvider.provide()
-            context.resources.configuration.locale.isO3Language,
-            true,
-            1
-        )
     )
 
   private fun languageIsActive(
@@ -411,7 +423,8 @@ class ZimManageViewModel @Inject constructor(
         .filter { it.isNotEmpty() }
         .subscribe(
             {
-              bookDao.insert(it.map { downloadStatus -> downloadStatus.toBookOnDisk() })
+              bookDao.insert(
+                  it.map { downloadStatus -> downloadStatus.toBookOnDisk(uriToFileConverter) })
               downloadDao.delete(
                   *it.map { status -> status.downloadId }.toLongArray()
               )

app/src/main/java/org/kiwix/kiwixmobile/zim_manager/fileselect_view/StorageObserver.kt

@@ -18,7 +18,7 @@ class StorageObserver @Inject constructor(
   private val downloadDao: NewDownloadDao
 ) {
 
-  private val _booksOnFileSystem = PublishProcessor.create<Collection<BookOnDisk>>()
+  private val _booksOnFileSystem = PublishProcessor.create<List<BookOnDisk>>()
   val booksOnFileSystem = _booksOnFileSystem.distinctUntilChanged()
       .doOnSubscribe {
         downloadDao.downloads()
@@ -37,7 +37,7 @@ class StorageObserver @Inject constructor(
       }
 
       override fun onScanCompleted() {
-        _booksOnFileSystem.onNext(foundBooks)
+        _booksOnFileSystem.onNext(foundBooks.toList())
 
       }
     }).scan(sharedPreferenceUtil.prefStorage)

app/src/main/java/org/kiwix/kiwixmobile/zim_manager/library_view/adapter/Language.kt

@@ -2,22 +2,32 @@ package org.kiwix.kiwixmobile.zim_manager.library_view.adapter
 
 import java.util.Locale
 
-class Language constructor(
+data class Language constructor(
-  locale: Locale,
   var active: Boolean,
   var occurencesOfLanguage: Int,
-  var language: String = locale.displayLanguage,
+  var language: String,
-  var languageLocalized: String = locale.getDisplayLanguage(locale),
+  var languageLocalized: String,
-  var languageCode: String = locale.isO3Language,
+  var languageCode: String,
-  var languageCodeISO2: String = locale.language
+  var languageCodeISO2: String
 ) {
+  constructor(
+    locale: Locale,
+    active: Boolean,
+    occurrencesOfLanguage: Int
+  ) : this(
+      active,
+      occurrencesOfLanguage,
+      locale.displayLanguage,
+      locale.getDisplayLanguage(locale),
+      locale.isO3Language,
+      locale.language
+  )
 
   constructor(
     languageCode: String,
     active: Boolean,
     occurrencesOfLanguage: Int
-  ) : this(Locale(languageCode), active, occurrencesOfLanguage) {
+  ) : this(Locale(languageCode), active, occurrencesOfLanguage)
-  }
 
   override fun equals(other: Any?): Boolean {
     return (other as Language).language == language && other.active == active

app/src/test/java/org/kiwix/kiwixmobile/InstantExecutorExtension.kt

@@ -0,0 +1,44 @@
+/*
+ * Kiwix Android
+ * Copyright (C) 2018  Kiwix <android.kiwix.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.kiwix.kiwixmobile
+
+import android.arch.core.executor.ArchTaskExecutor
+import android.arch.core.executor.TaskExecutor
+import org.junit.jupiter.api.extension.AfterEachCallback
+import org.junit.jupiter.api.extension.BeforeEachCallback
+import org.junit.jupiter.api.extension.ExtensionContext
+
+class InstantExecutorExtension : BeforeEachCallback, AfterEachCallback {
+
+  override fun beforeEach(context: ExtensionContext?) {
+    ArchTaskExecutor.getInstance()
+        .setDelegate(object : TaskExecutor() {
+          override fun executeOnDiskIO(runnable: Runnable) = runnable.run()
+
+          override fun postToMainThread(runnable: Runnable) = runnable.run()
+
+          override fun isMainThread(): Boolean = true
+        })
+  }
+
+  override fun afterEach(context: ExtensionContext?) {
+    ArchTaskExecutor.getInstance().setDelegate(null)
+  }
+
+}

app/src/test/java/org/kiwix/kiwixmobile/zim_manager/ZimManageViewModelTest.kt

@@ -0,0 +1,503 @@
+/*
+ * Kiwix Android
+ * Copyright (C) 2018  Kiwix <android.kiwix.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.kiwix.kiwixmobile.zim_manager
+
+import android.app.Application
+import com.jraska.livedata.test
+import io.mockk.clearMocks
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.verify
+import io.reactivex.Scheduler
+import io.reactivex.Single
+import io.reactivex.android.plugins.RxAndroidPlugins
+import io.reactivex.plugins.RxJavaPlugins
+import io.reactivex.processors.PublishProcessor
+import io.reactivex.schedulers.Schedulers
+import io.reactivex.schedulers.TestScheduler
+import org.junit.jupiter.api.AfterAll
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.Nested
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.extension.ExtendWith
+import org.kiwix.kiwixmobile.InstantExecutorExtension
+import org.kiwix.kiwixmobile.R
+import org.kiwix.kiwixmobile.database.newdb.dao.NewBookDao
+import org.kiwix.kiwixmobile.database.newdb.dao.NewDownloadDao
+import org.kiwix.kiwixmobile.database.newdb.dao.NewLanguagesDao
+import org.kiwix.kiwixmobile.downloader.Downloader
+import org.kiwix.kiwixmobile.downloader.model.BookOnDisk
+import org.kiwix.kiwixmobile.downloader.model.DownloadItem
+import org.kiwix.kiwixmobile.downloader.model.DownloadModel
+import org.kiwix.kiwixmobile.downloader.model.DownloadState
+import org.kiwix.kiwixmobile.downloader.model.DownloadStatus
+import org.kiwix.kiwixmobile.downloader.model.UriToFileConverter
+import org.kiwix.kiwixmobile.library.entity.LibraryNetworkEntity
+import org.kiwix.kiwixmobile.library.entity.LibraryNetworkEntity.Book
+import org.kiwix.kiwixmobile.network.KiwixService
+import org.kiwix.kiwixmobile.utils.BookUtils
+import org.kiwix.kiwixmobile.zim_manager.Fat32Checker.FileSystemState
+import org.kiwix.kiwixmobile.zim_manager.Fat32Checker.FileSystemState.CanWrite4GbFile
+import org.kiwix.kiwixmobile.zim_manager.Fat32Checker.FileSystemState.CannotWrite4GbFile
+import org.kiwix.kiwixmobile.zim_manager.NetworkState.CONNECTED
+import org.kiwix.kiwixmobile.zim_manager.NetworkState.NOT_CONNECTED
+import org.kiwix.kiwixmobile.zim_manager.fileselect_view.StorageObserver
+import org.kiwix.kiwixmobile.zim_manager.library_view.adapter.Language
+import org.kiwix.kiwixmobile.zim_manager.library_view.adapter.LibraryListItem
+import java.io.File
+import java.util.LinkedList
+import java.util.concurrent.TimeUnit.MILLISECONDS
+import java.util.concurrent.TimeUnit.SECONDS
+
+@ExtendWith(InstantExecutorExtension::class)
+class ZimManageViewModelTest {
+
+  private val newDownloadDao: NewDownloadDao = mockk()
+  private val newBookDao: NewBookDao = mockk()
+  private val newLanguagesDao: NewLanguagesDao = mockk()
+  private val downloader: Downloader = mockk()
+  private val storageObserver: StorageObserver = mockk()
+  private val kiwixService: KiwixService = mockk()
+  private val application: Application = mockk()
+  private val connectivityBroadcastReceiver: ConnectivityBroadcastReceiver = mockk()
+  private val bookUtils: BookUtils = mockk()
+  private val fat32Checker: Fat32Checker = mockk()
+  private val uriToFileConverter: UriToFileConverter = mockk()
+  lateinit var viewModel: ZimManageViewModel
+
+  private val downloads: PublishProcessor<List<DownloadModel>> = PublishProcessor.create()
+  private val booksOnFileSystem: PublishProcessor<List<BookOnDisk>> = PublishProcessor.create()
+  private val books: PublishProcessor<List<BookOnDisk>> = PublishProcessor.create()
+  private val languages: PublishProcessor<List<Language>> = PublishProcessor.create()
+  private val fileSystemStates: PublishProcessor<FileSystemState> = PublishProcessor.create()
+  private val networkStates: PublishProcessor<NetworkState> = PublishProcessor.create()
+
+  private val testScheduler = TestScheduler()
+
+  init {
+    setScheduler(testScheduler)
+  }
+
+  private fun setScheduler(replacementScheduler: Scheduler) {
+    RxJavaPlugins.setIoSchedulerHandler { scheduler -> replacementScheduler }
+    RxJavaPlugins.setComputationSchedulerHandler { scheduler -> replacementScheduler }
+    RxJavaPlugins.setNewThreadSchedulerHandler { scheduler -> replacementScheduler }
+    RxAndroidPlugins.setInitMainThreadSchedulerHandler { scheduler -> Schedulers.trampoline() }
+  }
+
+  @AfterAll
+  fun teardown() {
+    RxJavaPlugins.reset()
+    RxAndroidPlugins.reset();
+  }
+
+  private val defaultLanguageProvider: DefaultLanguageProvider = mockk()
+
+  @BeforeEach
+  fun init() {
+    clearMocks(
+        newDownloadDao, newBookDao, newLanguagesDao, downloader,
+        storageObserver, kiwixService, application, connectivityBroadcastReceiver, bookUtils,
+        fat32Checker, uriToFileConverter, defaultLanguageProvider
+    )
+    every { connectivityBroadcastReceiver.action } returns "test"
+    every { newDownloadDao.downloads() } returns downloads
+    every { newBookDao.books() } returns books
+    every { storageObserver.booksOnFileSystem } returns booksOnFileSystem
+    every { newLanguagesDao.languages() } returns languages
+    every { fat32Checker.fileSystemStates } returns fileSystemStates
+    every { connectivityBroadcastReceiver.networkStates } returns networkStates
+    every { application.registerReceiver(any(), any()) } returns mockk()
+    viewModel = ZimManageViewModel(
+        newDownloadDao, newBookDao, newLanguagesDao, downloader,
+        storageObserver, kiwixService, application, connectivityBroadcastReceiver, bookUtils,
+        fat32Checker, uriToFileConverter, defaultLanguageProvider
+    )
+    testScheduler.triggerActions()
+  }
+
+  @Nested
+  inner class Context {
+    @Test
+    fun `registers broadcastReceiver in init`() {
+      verify {
+        application.registerReceiver(connectivityBroadcastReceiver, any())
+      }
+    }
+
+    @Test
+    fun `unregisters broadcastReceiver in onCleared`() {
+      every { application.unregisterReceiver(any()) } returns mockk()
+      viewModel.onClearedExposed()
+      verify {
+        application.unregisterReceiver(connectivityBroadcastReceiver)
+      }
+    }
+  }
+
+  @Nested
+  inner class Downloads {
+    @Test
+    fun `on emission from database query and render downloads`() {
+      val expectedStatus = DownloadStatus()
+      expectStatusWith(listOf(expectedStatus))
+      viewModel.downloadItems
+          .test()
+          .assertValue(listOf(DownloadItem(expectedStatus)))
+          .dispose()
+    }
+
+    @Test
+    fun `on emission of successful status create a book and delete the download`() {
+      every { uriToFileConverter.convert(any()) } returns File("test")
+      val expectedStatus = DownloadStatus(
+          downloadId = 10L,
+          state = DownloadState.Successful
+      )
+      expectStatusWith(listOf(expectedStatus))
+      val element = expectedStatus.toBookOnDisk(uriToFileConverter)
+      verify {
+        newBookDao.insert(listOf(element))
+        newDownloadDao.delete(10L)
+      }
+    }
+
+    @Test
+    fun `if statuses don't have a matching Id for download in db over 3 secs then delete`() {
+      expectStatusWith(
+          listOf(DownloadStatus(downloadId = 1)),
+          listOf(DownloadModel(downloadId = 1), DownloadModel(downloadId = 3))
+      )
+      testScheduler.advanceTimeBy(3, SECONDS)
+      testScheduler.triggerActions()
+      verify {
+        newDownloadDao.delete(3)
+      }
+    }
+
+    @Test
+    fun `if statuses do have a matching Id for download in db over 3 secs then don't delete`() {
+      expectStatusWith(
+          listOf(DownloadStatus(downloadId = 1)),
+          listOf(DownloadModel(downloadId = 1))
+      )
+      testScheduler.advanceTimeBy(3, SECONDS)
+      testScheduler.triggerActions()
+      verify(exactly = 0) {
+        newDownloadDao.delete(any())
+      }
+    }
+
+    private fun expectStatusWith(
+      expectedStatuses: List<DownloadStatus>,
+      expectedDownloads: List<DownloadModel> = listOf(
+          DownloadModel()
+      )
+    ) {
+      val downloadList = expectedDownloads
+      every { downloader.queryStatus(downloadList) } returns expectedStatuses
+      downloads.offer(downloadList)
+      testScheduler.triggerActions()
+      testScheduler.advanceTimeBy(1, SECONDS)
+      testScheduler.triggerActions()
+    }
+  }
+
+  @Nested
+  inner class Books {
+    @Test
+    fun `emissions from DB sorted by title and observed`() {
+      books.onNext(
+          listOf(
+              BookOnDisk().apply { book.title = "z" },
+              BookOnDisk().apply { book.title = "a" }
+          )
+      )
+      testScheduler.triggerActions()
+      viewModel.bookItems.test()
+          .assertValue(
+              listOf(
+                  BookOnDisk().apply { book.title = "a" },
+                  BookOnDisk().apply { book.title = "z" }
+              )
+          )
+          .dispose()
+    }
+
+    @Test
+//    @Disabled("WithLatestFrom is not calling BiFunction removeBooksAlreadyInDao - revisit")
+    fun `books found on filesystem are filtered by books already in db`() {
+      val expectedBook = BookOnDisk().apply { book.id = "1" }
+      val bookToRemove = BookOnDisk().apply { book.id = "2" }
+      testScheduler.triggerActions()
+      viewModel.requestFileSystemCheck.onNext(Unit)
+      testScheduler.triggerActions()
+      books.onNext(listOf(bookToRemove))
+      testScheduler.triggerActions()
+      booksOnFileSystem.onNext(
+          listOf(
+              expectedBook,
+              expectedBook,
+              bookToRemove
+          )
+      )
+      testScheduler.triggerActions()
+      verify {
+        newBookDao.insert(listOf(expectedBook))
+      }
+    }
+  }
+
+  @Nested
+  inner class Lanuages {
+
+    @Test
+    fun `a network request with no result and an empty language db triggers an activation of the default locale`() {
+      val expectedLanguage = Language(
+          active = true,
+          occurencesOfLanguage = 1,
+          language = "eng",
+          languageLocalized = "englocal",
+          languageCode = "ENG",
+          languageCodeISO2 = "en"
+      )
+      expectNetworkDbAndDefault(
+          listOf(),
+          listOf(),
+          expectedLanguage
+      )
+      verify { newLanguagesDao.insert(listOf(expectedLanguage)) }
+    }
+
+    @Test
+    fun `a network request with no result and a non empty language db does not trigger anything`() {
+      expectNetworkDbAndDefault(
+          listOf(),
+          listOf(
+              Language(
+                  active = true,
+                  occurencesOfLanguage = 1,
+                  language = "eng",
+                  languageLocalized = "englocal",
+                  languageCode = "ENG",
+                  languageCodeISO2 = "en"
+              )
+          ),
+          Language(true, 1, "", "", "", "")
+      )
+      verify(exactly = 0) { newLanguagesDao.insert(any()) }
+    }
+
+    @Test
+    fun `a network request with a result and an empty language db triggers an activation of the default locale with the result of the web request`() {
+      val defaultLanguage = Language(
+          active = true,
+          occurencesOfLanguage = 1,
+          language = "English",
+          languageLocalized = "English",
+          languageCode = "eng",
+          languageCodeISO2 = "eng"
+      )
+      expectNetworkDbAndDefault(
+          listOf(
+              Book().apply { language = "eng" },
+              Book().apply { language = "eng" },
+              Book().apply { language = "fra" }
+          ),
+          listOf(),
+          defaultLanguage)
+      verify {
+        newLanguagesDao.insert(
+            listOf(
+                defaultLanguage.copy(occurencesOfLanguage = 2),
+                Language(
+                    active = false,
+                    occurencesOfLanguage = 1,
+                    language = "fra",
+                    languageLocalized = "",
+                    languageCode = "",
+                    languageCodeISO2 = ""
+                )
+            )
+        )
+      }
+    }
+
+    @Test
+    fun `a network request with a result and a non empty language db triggers an activation of the result of the web request with the db`() {
+      val dbLanguage = Language(
+          active = true,
+          occurencesOfLanguage = 1,
+          language = "English",
+          languageLocalized = "English",
+          languageCode = "eng",
+          languageCodeISO2 = "eng"
+      )
+      expectNetworkDbAndDefault(
+          listOf(
+              Book().apply { language = "eng" },
+              Book().apply { language = "eng" },
+              Book().apply { language = "fra" }
+          ),
+          listOf(dbLanguage),
+          Language(true, 1, "", "", "", "")
+      )
+      verify {
+        newLanguagesDao.insert(
+            listOf(
+                dbLanguage.copy(occurencesOfLanguage = 2),
+                Language(
+                    active = false,
+                    occurencesOfLanguage = 1,
+                    language = "fra",
+                    languageLocalized = "",
+                    languageCode = "",
+                    languageCodeISO2 = ""
+                )
+            )
+        )
+      }
+    }
+
+    private fun expectNetworkDbAndDefault(
+      networkBooks: List<Book>,
+      dbBooks: List<Language>,
+      defaultLanguage: Language
+    ) {
+      every { kiwixService.library } returns Single.just(
+          LibraryNetworkEntity().apply {
+            book = LinkedList(networkBooks)
+          })
+      val defaultLanguage = defaultLanguage
+      every { defaultLanguageProvider.provide() } returns defaultLanguage
+      languages.onNext(dbBooks)
+      testScheduler.triggerActions()
+      networkStates.onNext(CONNECTED)
+      testScheduler.triggerActions()
+    }
+  }
+
+  @Test
+  fun `network states observed`() {
+    networkStates.offer(NOT_CONNECTED)
+    viewModel.networkStates.test()
+        .assertValue(NOT_CONNECTED)
+        .dispose()
+  }
+
+  @Test
+  fun `language items for dialog observed`() {
+    val expectedValue = listOf(Language(true, 1, "e", "e", "e", "e"))
+    testScheduler.triggerActions()
+    languages.onNext(expectedValue)
+    testScheduler.triggerActions()
+    viewModel.requestLanguagesDialog.onNext(Unit)
+    testScheduler.triggerActions()
+    viewModel.languageItems.test()
+        .assertValue(expectedValue)
+        .dispose()
+  }
+
+  @Test
+  fun `library update removes from sources`() {
+    every { application.getString(R.string.your_languages) } returns "1"
+    every { application.getString(R.string.other_languages) } returns "2"
+    val bookAlreadyOnDisk = Book().apply {
+      id = "0"
+      url = ""
+    }
+    val bookDownloading = Book().apply {
+      id = "1"
+      url = ""
+    }
+    val bookWithStackExchange = Book().apply {
+      id = "2"
+      url = "blahblah/stack_exchange/"
+    }
+    val bookWithActiveLanguage = Book().apply {
+      id = "3"
+      language = "activeLanguage"
+      url = ""
+    }
+    val bookWithInactiveLanguage = Book().apply {
+      id = "3"
+      language = "inactiveLanguage"
+      url = ""
+    }
+    every { kiwixService.library } returns Single.just(
+        LibraryNetworkEntity().apply {
+          book = LinkedList(
+              listOf(
+                  bookAlreadyOnDisk,
+                  bookDownloading,
+                  bookWithStackExchange,
+                  bookWithActiveLanguage,
+                  bookWithInactiveLanguage
+              )
+          )
+        }
+    )
+    networkStates.onNext(CONNECTED)
+    downloads.onNext(listOf(DownloadModel(book = bookDownloading)))
+    books.onNext(listOf(BookOnDisk(book = bookAlreadyOnDisk)))
+    languages.onNext(
+        listOf(
+            Language(true, 1, "", "", "activeLanguage", ""),
+            Language(false, 1, "", "", "inactiveLanguage", "")
+        )
+    )
+    fileSystemStates.onNext(CanWrite4GbFile)
+    testScheduler.advanceTimeBy(500, MILLISECONDS)
+    testScheduler.triggerActions()
+    viewModel.libraryItems.test()
+        .assertValue(
+            listOf(
+                LibraryListItem.DividerItem(Long.MAX_VALUE, "1"),
+                LibraryListItem.BookItem(bookWithActiveLanguage),
+                LibraryListItem.DividerItem(Long.MIN_VALUE, "2"),
+                LibraryListItem.BookItem(bookWithInactiveLanguage)
+            )
+        )
+        .dispose()
+  }
+
+  @Test
+  fun `library filters out files over 4GB if file system state says to`() {
+    val bookOver4Gb = Book().apply {
+      id = "0"
+      url = ""
+      size = "${Fat32Checker.FOUR_GIGABYTES_IN_KILOBYTES + 1}"
+    }
+    every { kiwixService.library } returns Single.just(
+        LibraryNetworkEntity().apply {
+          book = LinkedList(listOf(bookOver4Gb))
+        }
+    )
+    networkStates.onNext(CONNECTED)
+    downloads.onNext(listOf())
+    books.onNext(listOf())
+    languages.onNext(listOf(Language(true, 1, "", "", "activeLanguage", "")))
+    fileSystemStates.onNext(CannotWrite4GbFile)
+    testScheduler.advanceTimeBy(500, MILLISECONDS)
+    testScheduler.triggerActions()
+    viewModel.libraryItems.test()
+        .assertValue(listOf())
+        .dispose()
+  }
+}

app/src/test/resources/io/mockk/settings.properties

@@ -0,0 +1 @@
+relaxUnitFun=true

app/src/test/resources/junit-platform.properties

@@ -0,0 +1 @@
+junit.jupiter.testinstance.lifecycle.default = per_class