Issues stubbing and capturing value classes in latest snapshot

[jselbo]

Hello,
I think there are issues introduced by the recent commits
d8fe7c7 "Add value class support to KArgumentCaptor"
cd674c4 "Add value class support to eq() argument matcher"

I am trying to integrate the latest mockito-kotlin snapshot build with our suite of tests and I'm encountering these issues with value classes that wrap primitive types (like kotlin.time.Duration):

1. anyOrNull with nullable primitive value class matcher throws IllegalStateException

See 7a19a0a for a repro and a fix - I can open a PR if desired but I don't want to step on the toes of existing work

2. any/eq don't work for primitive value class

@JvmInline value class PrimitiveValueClass(val value: Long)

// method:
fun nullablePrimitiveValueClass(v: PrimitiveValueClass?)

// test:
mock<SynchronousFunctions>().apply {
  nullablePrimitiveValueClass(PrimitiveValueClass(123))
  verify(this).nullablePrimitiveValueClass(any())
}

fails with:

Argument(s) are different! Wanted:
synchronousFunctions.nullablePrimitiveValueClass-2LcYgm0(
    <any long>
);
-> at test.MatchersTest$AnyOrNullMatchersTest.anyOrNullNullableValueClass(MatchersTest.kt:375)
Actual invocations have different arguments:
synchronousFunctions.nullablePrimitiveValueClass-2LcYgm0(
    PrimitiveValueClass(value=123)
);

I think the any() wrongly unwraps the value class type when it is not actually inlined here.

I also saw some failures related to kotlin.Result<T> unwrapping but I'm not sure if that's a separate issue.

cc: @m-koops

[m-koops]

Hi Joshua,

Many thanks for raising this issue and for sharing the commit with the fix in it.
That fix seems the right approach to me.

Please proceed with preparing the PR to get the fix merged into the project. This will help to support value classes in Mockito-Kotlin some more.

You have already included a test case for matching anyOrNull() against a null value as argument.
Can you please extend with test cases to match any(), anyOrNull(), eq() against a real instance of a PrimitiveValueClass argument? And can you also extend the interface SynchronousFunctions with a function like fun primitiveValueClassResult(): PrimitiveValueClass and add a test case to assert that the return value is properly stubbed by Mockito-Kotlin?

My final concern is about this PrimitiveValueClass being properly returned by stubbed suspend functions. But the combination of suspend functions with value class return values is not working well in general. I'm in teh process of preparing a fix for that soon. I will make sure to include test cases for stubbed suspend functions with PrimitiveValueClass argument and return value as well.

Finally, talking about kotlin.Result<T>, I'm pretty sure this is related to your fix. Result class has been implemented as value class, as the unsigned integer classes are (e.g. UShort and UInt). So, a proper value class support in Mockito-Kotlin will also provide support for those implementations.