Hi all :android-wave: , How to write integration t...

# koin

[Abhimanyu]

Hi all 👋 ,
How to write integration tests for application using Koin?

I am getting the following error when running my tests.

java.lang.IllegalStateException: KoinApplication has not been started

[Abhimanyu]

UI Test code

class HomeScreenTest {
    @get:Rule
    val composeTestRule = createAndroidComposeRule<MainActivity>()

    @Test
    fun homeScreenIsDisplayed() {
        composeTestRule.onNodeWithText("Home").assertIsDisplayed()
    }
}

[Abhimanyu]

Application class

class MyApplication : Application() {
    override fun onCreate() {
        super.onCreate()
        startKoin {
            modules(
                MyAppModule().module,
            )
        }
    }
}

[Abhimanyu]

MainActivity

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        enableEdgeToEdge()
        setContent {
            HomeScreen()
        }
    }
}

[Abhimanyu]

Tried adding startKoin directly in the test setup.
It didn't work.

@Before
fun setUp() {
  startKoin {
    modules(MyAppModule().module)
  }
}

[Abhimanyu]

Update: Issue Resolved.

Complete Setup

InstrumentationTestRunner

class InstrumentationTestRunner : AndroidJUnitRunner() {
    override fun newApplication(
        classLoader: ClassLoader?,
        className: String?,
        context: Context?
    ): Application {
        return super.newApplication(
            classLoader,
            TestApplication::class.java.name,
            context
        )
    }
}

KoinTestRule

class KoinTestRule(
    private val modules: List<Module>,
) : TestRule {
    override fun apply(
        base: Statement,
        description: Description,
    ): Statement {
        return object : Statement() {
            override fun evaluate() {
                try {
                    stopKoin()
                    startKoin {
                        androidContext(
                            androidContext = InstrumentationRegistry.getInstrumentation().targetContext,
                        )
                        modules(
                            modules = modules,
                        )
                    }
                    base.evaluate()
                } finally {
                    stopKoin()
                }
            }
        }
    }
}

TestApplication

class TestApplication : Application() {
    override fun onCreate() {
        super.onCreate()
        startKoin {
            androidLogger(
                level = Level.ERROR
            )
            androidContext(
                androidContext = this@TestApplication,
            )
            modules(
                modules = testApplicationModule,
            )
        }
    }
}

TestApplicationModule

val testApplicationModule = module { 
  // Add instrumented common test dependencies here
}

TestModule

internal val androidTestModule = module {
    // Add instrumented test-specific dependencies here
}

HomeScreenTest

@RunWith(AndroidJUnit4::class)
internal class HomeScreenTest {
    @get:Rule(order = 0)
    val koinTestRule = KoinTestRule(
        modules = listOf(
            MyAppModule().module,
            androidTestModule,
        ),
    )

    @get:Rule(order = 1)
    val composeTestRule = createAndroidComposeRule<MainActivity>()

    @Before
    fun setup() {
        // Setup will be added if needed
    }

    @Test
    fun homeScreen_isDisplayed() {
        composeTestRule.onNodeWithText("Home").assertIsDisplayed()
    }
}