Is it possible to achieve `@BeforeClass` behavior in Android/iOS common tests? kotlin.test has <the ...

# multiplatform

[Jeff Lockhart]

Is it possible to achieve @BeforeClass behavior in Android/iOS common tests? kotlin.test has the annotation for Kotlin/Native, as does Junit for JVM. My naive attempt to typealias the two doesn't work on the JVM side.

[ephemient]

if you are writing a multiplatform test, just use @kotlin.test.BeforeClass. it already has actual typealias defined in the kotlin-test-junit and kotlin-test-junit5 artifacts

[Jeff Lockhart]

That's what I would have thought, but there's no such annotation available to import in my common tests. Maybe I'm missing something.

[ephemient]

you do have

kotlin {
    sourceSets {
        commonTest {
            dependencies {
                implementation("org.jetbrains.kotlin:kotlin-test")

or something equivalent in your build.gradle?

[Big Chungus]

IDE sometimes does not suggest it. Try annotating by fully qualified path

[Jeff Lockhart]

Yeah, my dependencies are:

kotlin {
  sourceSets {
    ...
    val commonTest by getting {
      dependencies {
        implementation(kotlin("test"))
      }
    }
    ...
    val androidTest by getting {
      dependencies {
        implementation(kotlin("test-junit"))
      }
    }
  }
}

[ephemient]

it may be an IDE issue, then. try using @kotlin.test.BeforeAll or manually importing it as Martynas suggests

[Jeff Lockhart]

I've tried @kotlin.test.BeforeClass and I get the error:

Unresolved reference: BeforeClass

[ephemient]

in Gradle or in the IDE?

[Jeff Lockhart]

Same with @kotlin.test.BeforeAll

[Jeff Lockhart]

Both. The IDE shows the error. If I run the tests gradle outputs the same error.

[ephemient]

you could try adding

kotlin {
  sourceSets {
    val commonTest by getting {
      dependencies {
        implementation(kotlin("test"))
        implementation(kotlin("test-annotations-common"))
      }
    }
}

but that's odd, the same setup works in my projects. do you have a public project?

[Jeff Lockhart]

This is running the common tests on Android. If I run them on iOS, they run without error there.

[ephemient]

(I don't even have an ios target)

[Jeff Lockhart]

I tried adding the "test-annotations-common" and still no luck, same error.

[ephemient]

actually, just to check, you are aware of the difference between androidTest and androidAndroidTest right?

[Jeff Lockhart]

My project isn't public, yet.

[ephemient]

because if you are running instrumented tests, you need to add the dependency to the latter (the equivalent of androidTest in a non-multiplatform android project), not just the former (the equivalent of test in a non-multiplatform android project)

[Jeff Lockhart]

I have been able to use the @BeforeTest annotation. You have @BeforeClass working the same though?

[Jeff Lockhart]

I've only had unit tests up to this point, but I will need to get instrumented tests for the ones I'm working on now, the ones that need this annotation. What's the difference in the dependencies with KMM build.gradle.kts?

[Jeff Lockhart]

These tests need a context and file I/O.

[Jeff Lockhart]

(Haven't gotten to implementing the expect/actual for the I/O yet.)

[Jeff Lockhart]

From what I've gathered, the kotlin-test dependency includes kotlin-test-common and kotlin-test-annotations-common. annotations-common contains only 4 annotations: Tests, Ignore, BeforeTest, and AfterTest. Their definitions are pretty close to what I was attempting to typealias `BeforeClass`:

@Target(AnnotationTarget.FUNCTION)
public expect annotation class BeforeTest()

The kotlin-test-junit dependency defines the jvm actual:

public typealias BeforeTest = org.junit.Before

Again, similar to what I was attempting for BeforeClass. There must be some reason that this typealias doesn't work for this annotation. Not sure why though.

[ephemient]

ah, I see. it works for native-only, but not on common. https://youtrack.jetbrains.com/issue/KT-49141/Support-some-kind-of-BeforeClass-AfterClass-in-common-tests

[Jeff Lockhart]

Interesting there hasn't been a response from JetBrains. Curious as to why this particular test annotation isn't as straightforward to typealias as those others.

[Jeff Lockhart]

Testing further, while my expect/actual typealias gives errors in the IDE:

Expected annotation class 'BeforeClass' has no actual declaration in module ...androidTest (test) for JVM

Actual typealias 'BeforeClass' has no corresponding expected declaration

The tests still compile and run, but my function annotated @BeforeClass does not get run at all.

[Jeff Lockhart]

If I make my own versions of BeforeTest and AfterTest, with the same typealiasing, I get the same IDE errors. But the tests run and the annotations work as expected. So the IDE errors don't seem to have anything to do with the issue. There just seems to be something specific about the Junit BeforeClass behavior that doesn't work from common tests.

[Jeff Lockhart]

Ah, actually I just got it working with my typealias definition. I was just missing the required @JvmStatic annotation! So really, the kotlin team should be able to add these annotations to the common annotations library.

[ephemient]

now that I recall some more, I believe there isn't an equivalent across all the JS test frameworks that Kotlin/JS supports

[ephemient]

but if they drop older versions I think it might be doable

[Jeff Lockhart]

Seems like should be able to add support at least to the platforms/frameworks that support it.