Issue mozilla-mobile#2883: Introduce TabCollectionWithTabs data type …

…for joining over collections and tabs.

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

@@ -54,8 +54,8 @@ class TabCollectionDaoTest {
 
         assertEquals(2, pagedList.size)
 
-        assertEquals("Collection Two", pagedList[0]!!.title)
-        assertEquals("Collection One", pagedList[1]!!.title)
+        assertEquals("Collection Two", pagedList[0]!!.collection.title)
+        assertEquals("Collection One", pagedList[1]!!.collection.title)
     }
 
     @Test
@@ -81,8 +81,8 @@ class TabCollectionDaoTest {
 
         assertEquals(2, pagedList.size)
 
-        assertEquals("Updated collection", pagedList[0]!!.title)
-        assertEquals("Collection Two", pagedList[1]!!.title)
+        assertEquals("Updated collection", pagedList[0]!!.collection.title)
+        assertEquals("Collection Two", pagedList[1]!!.collection.title)
     }
 
     @Test
@@ -107,7 +107,7 @@ class TabCollectionDaoTest {
 
         assertEquals(2, pagedList.size)
 
-        assertEquals("Collection Three", pagedList[0]!!.title)
-        assertEquals("Collection One", pagedList[1]!!.title)
+        assertEquals("Collection Three", pagedList[0]!!.collection.title)
+        assertEquals("Collection One", pagedList[1]!!.collection.title)
     }
 }

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

@@ -5,6 +5,7 @@
 package mozilla.components.feature.tab.collections.db
 
 import android.content.Context
+import androidx.paging.PagedList
 import androidx.room.Room
 import androidx.test.core.app.ApplicationProvider
 import org.junit.After
@@ -58,10 +59,18 @@ class TabDaoTest {
             it.id = tabDao.insertTab(it)
         }
 
-        val tabs = tabDao.getTabsOfCollection(collection.id!!)
-        assertEquals(2, tabs.size)
-        assertEquals(tab2, tabs[0])
-        assertEquals(tab1, tabs[1])
+        val dataSource = tabCollectionDao.getTabCollectionsPaged()
+            .create()
+
+        val pagedList = PagedList.Builder(dataSource, 10)
+            .setNotifyExecutor(executor)
+            .setFetchExecutor(executor)
+            .build()
+
+        assertEquals(1, pagedList.size)
+        assertEquals(2, pagedList[0]!!.tabs.size)
+        assertEquals(tab1, pagedList[0]!!.tabs[0])
+        assertEquals(tab2, pagedList[0]!!.tabs[1])
     }
 
     @Test
@@ -92,9 +101,17 @@ class TabDaoTest {
 
         tabDao.deleteTab(tab1)
 
-        val tabs = tabDao.getTabsOfCollection(collection.id!!)
-        assertEquals(1, tabs.size)
-        assertEquals(tab2, tabs[0])
+        val dataSource = tabCollectionDao.getTabCollectionsPaged()
+            .create()
+
+        val pagedList = PagedList.Builder(dataSource, 10)
+            .setNotifyExecutor(executor)
+            .setFetchExecutor(executor)
+            .build()
+
+        assertEquals(1, pagedList.size)
+        assertEquals(1, pagedList[0]!!.tabs.size)
+        assertEquals(tab2, pagedList[0]!!.tabs[0])
     }
 
     @After

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

@@ -25,6 +25,11 @@ internal interface TabCollectionDao {
     @Update
     fun updateTabCollection(collection: TabCollectionEntity)
 
-    @Query("SELECT * FROM tab_collections ORDER BY created_at DESC")
-    fun getTabCollectionsPaged(): DataSource.Factory<Int, TabCollectionEntity>
+    @Query("""
+        SELECT *
+        FROM tab_collections LEFT JOIN tabs ON tab_collections.id = tab_collection_id
+        GROUP BY tab_collections.id
+        ORDER BY created_at DESC
+    """)
+    fun getTabCollectionsPaged(): DataSource.Factory<Int, TabCollectionWithTabs>
 }

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

@@ -0,0 +1,19 @@
+/* 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.feature.tab.collections.db
+
+import androidx.room.Embedded
+import androidx.room.Relation
+
+/**
+ * Class representing a [TabCollectionEntity] joined with its [TabEntity] instances.
+ */
+internal class TabCollectionWithTabs {
+    @Embedded
+    lateinit var collection: TabCollectionEntity
+
+    @Relation(parentColumn = "id", entityColumn = "tab_collection_id")
+    lateinit var tabs: List<TabEntity>
+}

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

@@ -7,7 +7,6 @@ package mozilla.components.feature.tab.collections.db
 import androidx.room.Dao
 import androidx.room.Delete
 import androidx.room.Insert
-import androidx.room.Query
 
 /**
  * Internal DAO for accessing [TabEntity] instances.
@@ -19,7 +18,4 @@ internal interface TabDao {
 
     @Delete
     fun deleteTab(tab: TabEntity)
-
-    @Query("SELECT * FROM tabs WHERE tab_collection_id = :tabCollectionId ORDER BY created_at ASC")
-    fun getTabsOfCollection(tabCollectionId: Long): List<TabEntity>
 }