Improve database tests

app/src/androidTest/java/org/koitharu/kotatsu/core/db/MangaDatabaseTest.kt

@@ -6,8 +6,6 @@ import androidx.test.platform.app.InstrumentationRegistry
 import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
-import org.koitharu.kotatsu.core.db.migrations.*
-import java.io.IOException
 import kotlin.test.assertEquals
 
 @RunWith(AndroidJUnit4::class)
@@ -19,10 +17,20 @@ class MangaDatabaseTest {
 		MangaDatabase::class.java,
 	)
 
+	private val migrations = databaseMigrations
+
 	@Test
-	@Throws(IOException::class)
-	fun migrateAll() {
+	fun versions() {
+		assertEquals(1, migrations.first().startVersion)
+		repeat(migrations.size) { i ->
+			assertEquals(i + 1, migrations[i].startVersion)
+			assertEquals(i + 2, migrations[i].endVersion)
+		}
 		assertEquals(DATABASE_VERSION, migrations.last().endVersion)
+	}
+
+	@Test
+	fun migrateAll() {
 		helper.createDatabase(TEST_DB, 1).close()
 		for (migration in migrations) {
 			helper.runMigrationsAndValidate(
@@ -34,22 +42,16 @@ class MangaDatabaseTest {
 		}
 	}
 
+	@Test
+	fun prePopulate() {
+		val resources = InstrumentationRegistry.getInstrumentation().targetContext.resources
+		helper.createDatabase(TEST_DB, DATABASE_VERSION).use {
+			DatabasePrePopulateCallback(resources).onCreate(it)
+		}
+	}
+
 	private companion object {
 
 		const val TEST_DB = "test-db"
-
-		val migrations = arrayOf(
-			Migration1To2(),
-			Migration2To3(),
-			Migration3To4(),
-			Migration4To5(),
-			Migration5To6(),
-			Migration6To7(),
-			Migration7To8(),
-			Migration8To9(),
-			Migration9To10(),
-			Migration10To11(),
-			Migration11To12(),
-		)
 	}
 }

app/src/main/java/org/koitharu/kotatsu/core/db/MangaDatabase.kt

@@ -4,6 +4,7 @@ import android.content.Context
 import androidx.room.Database
 import androidx.room.Room
 import androidx.room.RoomDatabase
+import androidx.room.migration.Migration
 import org.koitharu.kotatsu.bookmarks.data.BookmarkEntity
 import org.koitharu.kotatsu.bookmarks.data.BookmarksDao
 import org.koitharu.kotatsu.core.db.dao.MangaDao
@@ -65,22 +66,23 @@ abstract class MangaDatabase : RoomDatabase() {
 	abstract val scrobblingDao: ScrobblingDao
 }
 
-fun MangaDatabase(context: Context): MangaDatabase = Room.databaseBuilder(
-	context,
-	MangaDatabase::class.java,
-	"kotatsu-db"
-).addMigrations(
-	Migration1To2(),
-	Migration2To3(),
-	Migration3To4(),
-	Migration4To5(),
-	Migration5To6(),
-	Migration6To7(),
-	Migration7To8(),
-	Migration8To9(),
-	Migration9To10(),
-	Migration10To11(),
-	Migration11To12(),
-).addCallback(
-	DatabasePrePopulateCallback(context.resources)
-).build()
+val databaseMigrations: Array<Migration>
+	get() = arrayOf(
+		Migration1To2(),
+		Migration2To3(),
+		Migration3To4(),
+		Migration4To5(),
+		Migration5To6(),
+		Migration6To7(),
+		Migration7To8(),
+		Migration8To9(),
+		Migration9To10(),
+		Migration10To11(),
+		Migration11To12(),
+	)
+
+fun MangaDatabase(context: Context): MangaDatabase = Room
+	.databaseBuilder(context, MangaDatabase::class.java, "kotatsu-db")
+	.addMigrations(*databaseMigrations)
+	.addCallback(DatabasePrePopulateCallback(context.resources))
+	.build()