测试室作为 JUnit 测试而不是 AndroidTest

Question

尝试使用 MigrationTestHelper 类和 Robolectric 测试房间迁移。我们希望将其作为 JUnit 测试，因为我们的 CI 环境无法启动模拟器。 （请不要为模拟器提供 CI 修复的答案，CI 不在我的控制范围内）我 唯一的问题是测试失败，因为它找不到模式。我的 build.gradle 已经有这个了

android {
    sourceSets {
        test.assets.srcDirs += files("$projectDir/schemas".toString())
        androidTest.assets.srcDirs += files("$projectDir/schemas".toString())

    test {
        java.srcDirs += "$projectDir/src/sharedTest/java"
    }

    testOptions {
        unitTests {
            includeAndroidResources = true
        }
        unitTests.all {
            systemProperty 'robolectric.enabledSdks', '21'
        }
    }
}
dependencies {
   // has all the proper dependencies from mockito adn robolectric to kotlin and junit.
}

这是测试代码，但同样主要是在调用数据库创建时找不到模式。json 文件也在架构目录中

@RunWith(RobolectricTestRunner::class)
class Migration19To20Test {
    private val migration = MyDatabase.MIGRATION_19_20
    private val fromVersion = 19
    private val toVersion = 20

    @get:Rule
    val helper: MigrationTestHelper = MigrationTestHelper(
            InstrumentationRegistry.getInstrumentation(),
            MyDatabase::class.java.canonicalName,
            FrameworkSQLiteOpenHelperFactory())

    private val testDatabaseName = "migration-test"

    @Test
    fun insertsFirmwareVersionFullColumn() {
        givenADatabase()

        val validateDroppedTables = true
        val db = helper.runMigrationsAndValidate(
                testDatabaseName,
                toVersion,
                validateDroppedTables,
                migration)

        db.query("select * from ${DatabaseConstants.Table.People}").use { cursor ->
            cursor.moveToFirst()
            assertTrue("table should contain the ${DatabaseConstants.Column.People.NAME_FULL} column as it should have been added",
                    cursor.columnNames.contains(DatabaseConstants.Column.People.NAME_FULL))
        }
    }

    private fun givenADatabase() {
        // Test fails here
        helper.createDatabase(testDatabaseName, fromVersion)
    }
}

Answer 1

我通过复制MigrationTestHelper到我的测试源代码并修改 loadSchema 方法来解决它，如下所示

    private SchemaBundle loadSchema(Context context, int version) throws IOException {
//        InputStream input = context.getAssets().open(mAssetsFolder + "/" + version + ".json");
        InputStream input = new FileInputStream("./schemas/" + mAssetsFolder + "/" + version + ".json");
        return SchemaBundle.deserialize(input);
    }

该schemas目录在build.gradle中配置

android {
    defaultConfig {
        javaCompileOptions {
            annotationProcessorOptions {
                arguments = [
                        "room.schemaLocation"  : "$projectDir/schemas".toString(),
                        "room.incremental"     : "true",
                        "room.expandProjection": "true"]
            }
        }
    }
}

正如您所看到的，原因是此类在目录中查找迁移，assets因为 Google 假设您将在设备上运行这些迁移。在这种情况下，您必须将它们作为 Android 资产的一部分包含在内。

使用 Robolectric，它只是从目录中读取并将其放入流中。