Merge #7300

7300: Remove LiveData.awaitValue r=Amejia481 a=NotWoods

This function is causing a lot of headache because it forces support-android-test to depend on LiveData, which causes issues with other components that depend on support-android-test. We're working on switching from LiveData to Flow everywhere, so this change switches all the components that use the `awaitValue` function.
Co-authored-by: Tiger Oakes <toakes@mozilla.com>

buildSrc/src/main/java/Dependencies.kt

@@ -52,7 +52,7 @@ object Versions {
         const val lifecycle = "2.2.0"
         const val media = "1.1.0"
         const val work = "2.2.0"
-        const val arch_core_testing = "2.1.0"
+        const val arch = "2.1.0"
         const val uiautomator = "2.2.0"
         const val localbroadcastmanager = "1.0.0"
         const val swiperefreshlayout = "1.0.0"
@@ -82,7 +82,8 @@ object Dependencies {
 
     const val androidx_annotation = "androidx.annotation:annotation:${Versions.AndroidX.annotation}"
     const val androidx_appcompat = "androidx.appcompat:appcompat:${Versions.AndroidX.appcompat}"
-    const val androidx_arch_core_testing = "androidx.arch.core:core-testing:${Versions.AndroidX.arch_core_testing}"
+    const val androidx_arch_core_common = "androidx.arch.core:core-common:${Versions.AndroidX.arch}"
+    const val androidx_arch_core_testing = "androidx.arch.core:core-testing:${Versions.AndroidX.arch}"
     const val androidx_browser = "androidx.browser:browser:${Versions.AndroidX.browser}"
     const val androidx_cardview = "androidx.cardview:cardview:${Versions.AndroidX.cardview}"
     const val androidx_constraintlayout = "androidx.constraintlayout:constraintlayout:${Versions.AndroidX.constraintlayout}"

components/feature/tab-collections/src/androidTest/java/mozilla/components/feature/tab/collections/TabCollectionStorageTest.kt

@@ -10,6 +10,8 @@ import androidx.arch.core.executor.testing.InstantTaskExecutorRule
 import androidx.paging.PagedList
 import androidx.room.Room
 import androidx.test.core.app.ApplicationProvider
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.runBlocking
 import mozilla.components.browser.session.Session
 import mozilla.components.browser.session.SessionManager
 import mozilla.components.concept.engine.DefaultSettings
@@ -21,13 +23,11 @@ import mozilla.components.concept.engine.Settings
 import mozilla.components.concept.engine.utils.EngineVersion
 import mozilla.components.feature.tab.collections.db.TabCollectionDatabase
 import mozilla.components.feature.tab.collections.db.TabEntity
-import mozilla.components.support.android.test.awaitValue
 import mozilla.components.support.ktx.java.io.truncateDirectory
 import org.json.JSONObject
 import org.junit.After
 import org.junit.Assert.assertEquals
 import org.junit.Assert.assertNotEquals
-import org.junit.Assert.assertNotNull
 import org.junit.Before
 import org.junit.Rule
 import org.junit.Test
@@ -220,7 +220,7 @@ class TabCollectionStorageTest {
 
     @Test
     @Suppress("ComplexMethod")
-    fun testGettingCollectionsWithLimit() {
+    fun testGettingCollectionsWithLimit() = runBlocking {
         storage.createCollection(
             "Articles", listOf(
                 Session("https://www.mozilla.org").apply { title = "Mozilla" }
@@ -249,10 +249,8 @@ class TabCollectionStorageTest {
             )
         )
 
-        val collections = storage.getCollections(limit = 4)
-            .awaitValue()
+        val collections = storage.getCollections(limit = 4).first()
 
-        assertNotNull(collections!!)
         assertEquals(4, collections.size)
 
         with(collections[0]) {
@@ -290,7 +288,7 @@ class TabCollectionStorageTest {
     }
 
     @Test
-    fun testGettingTabCollectionCount() {
+    fun testGettingTabCollectionCount() = runBlocking {
         assertEquals(0, storage.getTabCollectionsCount())
 
         storage.createCollection(
@@ -306,9 +304,7 @@ class TabCollectionStorageTest {
 
         assertEquals(2, storage.getTabCollectionsCount())
 
-        val collections = storage.getCollections(limit = 2)
-            .awaitValue()
-        assertNotNull(collections!!)
+        val collections = storage.getCollections(limit = 2).first()
         assertEquals(2, collections.size)
 
         storage.removeCollection(collections[0])

components/feature/tab-collections/src/androidTest/java/mozilla/components/feature/tab/collections/db/TabCollectionDaoTest.kt

@@ -9,10 +9,10 @@ import androidx.arch.core.executor.testing.InstantTaskExecutorRule
 import androidx.paging.PagedList
 import androidx.room.Room
 import androidx.test.core.app.ApplicationProvider
-import mozilla.components.support.android.test.awaitValue
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.runBlocking
 import org.junit.After
 import org.junit.Assert.assertEquals
-import org.junit.Assert.assertNotNull
 import org.junit.Before
 import org.junit.Rule
 import org.junit.Test
@@ -119,7 +119,7 @@ class TabCollectionDaoTest {
     }
 
     @Test
-    fun testGettingCollectionsWithLimit() {
+    fun testGettingCollectionsWithLimit() = runBlocking {
         val collection1 = TabCollectionEntity(title = "Collection One", updatedAt = 10)
         val collection2 = TabCollectionEntity(title = "Collection Two", updatedAt = 50)
 
@@ -128,8 +128,7 @@ class TabCollectionDaoTest {
 
         val data = tabCollectionDao.getTabCollections(4)
 
-        val collections = data.awaitValue()
-        assertNotNull(collections!!)
+        val collections = data.first()
         assertEquals(2, collections.size)
         assertEquals("Collection Two", collections[1].collection.title)
         assertEquals("Collection One", collections[0].collection.title)

components/feature/tab-collections/src/main/java/mozilla/components/feature/tab/collections/TabCollectionStorage.kt

@@ -5,9 +5,9 @@
 package mozilla.components.feature.tab.collections
 
 import android.content.Context
-import androidx.lifecycle.LiveData
-import androidx.lifecycle.Transformations
 import androidx.paging.DataSource
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.map
 import mozilla.components.browser.session.Session
 import mozilla.components.browser.session.SessionManager
 import mozilla.components.browser.session.ext.writeSnapshotItem
@@ -108,15 +108,13 @@ class TabCollectionStorage(
         .map { entity -> TabCollectionAdapter(entity) }
 
     /**
-     * Returns the last [TabCollection] instances (up to [limit]) as a [LiveData] list.
+     * Returns the last [TabCollection] instances (up to [limit]) as a [Flow] list.
      *
      * @param limit (Optional) Maximum number of [TabCollection] instances that should be returned.
      */
-    fun getCollections(limit: Int = 20): LiveData<List<TabCollection>> {
+    fun getCollections(limit: Int = 20): Flow<List<TabCollection>> {
         limit.hashCode()
-        return Transformations.map(
-            database.value.tabCollectionDao().getTabCollections(limit)
-        ) { list ->
+        return database.value.tabCollectionDao().getTabCollections(limit).map { list ->
             list.map { entity -> TabCollectionAdapter(entity) }
         }
     }

components/feature/tab-collections/src/main/java/mozilla/components/feature/tab/collections/db/TabCollectionDao.kt

@@ -4,7 +4,6 @@
 
 package mozilla.components.feature.tab.collections.db
 
-import androidx.lifecycle.LiveData
 import androidx.paging.DataSource
 import androidx.room.Dao
 import androidx.room.Delete
@@ -12,6 +11,7 @@ import androidx.room.Insert
 import androidx.room.Query
 import androidx.room.Transaction
 import androidx.room.Update
+import kotlinx.coroutines.flow.Flow
 
 /**
  * Internal DAO for accessing [TabCollectionEntity] instances.
@@ -43,7 +43,7 @@ internal interface TabCollectionDao {
         ORDER BY created_at DESC
         LIMIT :limit
     """)
-    fun getTabCollections(limit: Int): LiveData<List<TabCollectionWithTabs>>
+    fun getTabCollections(limit: Int): Flow<List<TabCollectionWithTabs>>
 
     @Query("SELECT COUNT(*) FROM tab_collections")
     fun countTabCollections(): Int

components/feature/top-sites/src/androidTest/java/mozilla/components/feature/top/sites/TopSiteStorageTest.kt

@@ -12,9 +12,10 @@ import androidx.room.testing.MigrationTestHelper
 import androidx.sqlite.db.framework.FrameworkSQLiteOpenHelperFactory
 import androidx.test.core.app.ApplicationProvider
 import androidx.test.platform.app.InstrumentationRegistry
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.runBlocking
 import mozilla.components.feature.top.sites.db.Migrations
 import mozilla.components.feature.top.sites.db.TopSiteDatabase
-import mozilla.components.support.android.test.awaitValue
 import org.junit.After
 import org.junit.Assert.assertEquals
 import org.junit.Assert.assertFalse
@@ -97,13 +98,13 @@ class TopSiteStorageTest {
     }
 
     @Test
-    fun testGettingTopSites() {
+    fun testGettingTopSites() = runBlocking {
         storage.addTopSite("Mozilla", "https://www.mozilla.org")
         storage.addTopSite("Firefox", "https://www.firefox.com", isDefault = true)
 
-        val topSites = storage.getTopSites().awaitValue()
+        val topSites = storage.getTopSites().first()
 
-        assertNotNull(topSites!!)
+        assertNotNull(topSites)
         assertEquals(2, topSites.size)
 
         with(topSites[0]) {

components/feature/top-sites/src/main/java/mozilla/components/feature/top/sites/TopSiteStorage.kt

@@ -5,9 +5,9 @@
 package mozilla.components.feature.top.sites
 
 import android.content.Context
-import androidx.lifecycle.LiveData
-import androidx.lifecycle.Transformations
 import androidx.paging.DataSource
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.map
 import mozilla.components.feature.top.sites.adapter.TopSiteAdapter
 import mozilla.components.feature.top.sites.db.TopSiteDatabase
 import mozilla.components.feature.top.sites.db.TopSiteEntity
@@ -40,12 +40,10 @@ class TopSiteStorage(
     }
 
     /**
-     * Returns a [LiveData] list of all the [TopSite] instances.
+     * Returns a [Flow] list of all the [TopSite] instances.
      */
-    fun getTopSites(): LiveData<List<TopSite>> {
-        return Transformations.map(
-            database.value.topSiteDao().getTopSites()
-        ) { list ->
+    fun getTopSites(): Flow<List<TopSite>> {
+        return database.value.topSiteDao().getTopSites().map { list ->
             list.map { entity -> TopSiteAdapter(entity) }
         }
     }

components/feature/top-sites/src/main/java/mozilla/components/feature/top/sites/db/TopSiteDao.kt

@@ -4,13 +4,13 @@
 
 package mozilla.components.feature.top.sites.db
 
-import androidx.lifecycle.LiveData
 import androidx.paging.DataSource
 import androidx.room.Dao
 import androidx.room.Delete
 import androidx.room.Insert
 import androidx.room.Query
 import androidx.room.Transaction
+import kotlinx.coroutines.flow.Flow
 
 /**
  * Internal DAO for accessing [TopSiteEntity] instances.
@@ -25,7 +25,7 @@ internal interface TopSiteDao {
 
     @Transaction
     @Query("SELECT * FROM top_sites")
-    fun getTopSites(): LiveData<List<TopSiteEntity>>
+    fun getTopSites(): Flow<List<TopSiteEntity>>
 
     @Transaction
     @Query("SELECT * FROM top_sites")

components/support/android-test/build.gradle

@@ -32,7 +32,7 @@ android {
 
 dependencies {
     implementation Dependencies.kotlin_stdlib
-    implementation Dependencies.androidx_lifecycle_livedata
+    implementation Dependencies.androidx_arch_core_common
     implementation Dependencies.androidx_espresso_core
     implementation Dependencies.androidx_test_core
     implementation Dependencies.testing_leakcanary

components/support/android-test/src/main/java/mozilla/components/support/android/test/LiveData.kt

-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-package mozilla.components.support.android.test
-
-import androidx.lifecycle.LiveData
-import androidx.lifecycle.Observer
-import java.util.concurrent.CountDownLatch
-import java.util.concurrent.TimeUnit
-
-/**
- * Subscribes to the [LiveData] object and blocks until a value was observed. Returns the value or throws
- * [InterruptedException] if no value was observed in the given [timeout] (using [unit]).
- *
- * This is helpful for tests using [LiveData] objects that won't contain any data unless observed (e.g. LiveData objects
- * returned by Room).
- */
-@Throws(InterruptedException::class)
-fun <T> LiveData<T>.awaitValue(
-    timeout: Long = 1,
-    unit: TimeUnit = TimeUnit.SECONDS
-): T? {
-    val latch = CountDownLatch(1)
-    var value: T? = null
-
-    val observer = object : Observer<T> {
-        override fun onChanged(t: T?) {
-            value = t
-            removeObserver(this)
-            latch.countDown()
-        }
-    }
-
-    observeForever(observer)
-
-    latch.await(timeout, unit)
-
-    return value
-}

docs/changelog.md

@@ -58,6 +58,12 @@ permalink: /changelog/
   * ⚠️ **This is a breaking change**: `WebAppHideToolbarFeature` now takes `BrowserStore` instead of `SessionManager`. `trustedScopes` is now derived from `CustomTabsServiceStore` and `WebAppManifest`.
   * ⚠️ **This is a breaking change**: `onToolbarVisibilityChange` has been removed. You should now observe `BrowserStore` instead.
 
+* **feature-tab-collections**:
+  * ⚠️ **This is a breaking change**: `TabCollectionStorage.getCollections` now returns `Flow` instead of `LiveData`. Use `Flow.asLiveData` to convert the result into a `LiveData` again.
+
+* **feature-top-sites**:
+  * ⚠️ **This is a breaking change**: `TopSiteStorage.getTopSites` now returns `Flow` instead of `LiveData`. Use `Flow.asLiveData` to convert the result into a `LiveData` again.
+
 # 44.0.0
 
 * [Commits](https://github.com/mozilla-mobile/android-components/compare/v43.0.0...v44.0.0)