Seems like there’s breaking changes to `checkModules()` in 3.1.0. Nothing in the changelog about it...

# koin

[russhwolf]

Seems like there’s breaking changes to checkModules() in 3.1.0. Nothing in the changelog about it. What’s the story there? I’m having trouble understanding how to migrate my tests from the lambda-based setup I had before.

[russhwolf]

I used to be doing this, essentially:

try {
    val koinApplication = startKoin { ... }

    koinApplication.koin.checkModules {
        koin.createScope(testScopeId, koinUiScopeQualifier)
        create<LocationDetailViewModel> { parametersOf(1L) }
    }
} finally {
    stopKoin()
}

I have a custom scope in my koin configuration, so I needed the createScope() call in the test to mimic what the prod code was doing.

[russhwolf]

But now the checkModules() that takes a lambda is gone. So I’m trying something like this

try {
    val koinApplication = startKoin { ... }

    koinApplication.koin.createScope(testScopeId, koinUiScopeQualifier)
    koinApplication.checkModules(mapOf(Long::class to 1L))
} finally {
    stopKoin()
}

This gives me java.lang.IllegalStateException: Missing MockProvider, which I think means I’m not wiring something up correctly because I’m not using mocks in my tests, so I assume the error is just because it can’t find something it’s looking for.

[John O'Reilly]

@russhwolf I had run in to exact same issue and had intended to get back to it again....but completely forgot!

fwiw I just made following updates based on sample that's in Koin repo....not sure if there's different/better way but seemed like that MockProviderRule is needed now...

https://github.com/joreilly/PeopleInSpace/commit/57e2eea1cba8538602f4d28ac55c8c3a2f9084bf

[russhwolf]

That only works for JVM though

[John O'Reilly]

ah, good point

[John O'Reilly]

I have that test in my app module right now....but probably should have it in common code....

[russhwolf]

yeah I 100% want to be testing my native modules too

[russhwolf]

they’re not always the same as JVM

[russhwolf]

Here’s a minimal sample of a test that fails looking for a MockProvider. That graph shouldn’t need to mock anything, and it’s actually impossible to interact with MockProvider from native anyway because it includes mutable state in a top-level object which leads to an InvalidMutabilityException when you call register().

class Box(val contents: String)

class KoinModulesTest {
    @Test
    fun checkModulesTest() {
        val koinApplication = startKoin {
            modules(module {
                single { "foo" }
                single { Box(get()) }
            })
        }

        koinApplication.checkModules()
    }

    @AfterTest
    fun tearDown() {
        stopKoin()
    }
}

[russhwolf]

https://github.com/InsertKoinIO/koin/issues/1115

[arnaud.giuliani]

Yes checkModules is simplified, following the new internals

[arnaud.giuliani]

yes, missed to add to it to changelog 👍

[arnaud.giuliani]

thanks for your feedback

[arnaud.giuliani]

I’ve tried to propose something to avoid create values. The idea is to mock definitions that have passed, a kindof sandbox execution.

[arnaud.giuliani]

/**
 * Check all definition's dependencies - start all modules and check if definitions can run
 */
fun KoinApplication.checkModules(
    defaultValues: Map<KClass<*>, Any> = hashMapOf(),
    allowedMocks: List<KClass<*>> = listOf(),
    allowedExceptions: List<KClass<*>> = listOf()
) = koin.checkModules(defaultValues, allowedMocks, allowedExceptions)

[arnaud.giuliani]

like this usage:

checkModules(
    allowedMocks = listOf(
        WorkerParameters::class,
        SavedStateHandle::class
    ),
    allowedExceptions = listOf(
        NullPointerException::class
    )
){
    androidContext(MockProvider.makeMock<Application>())
    modules(allModules)
}

[russhwolf]

What does usage look like if I don't want mocks? I don't see any way to avoid the internal calls into MockProvider

[arnaud.giuliani]

let me revert to old API, was not a good idea for such breakings 😕