Hey guys, I have a question! Given this ```sealed interface A { data class B(...): A data cl...

# mockk

[Davide Giuseppe Farella]

Hey guys, I have a question!

Given this

sealed interface A {
  
  data class B(...): A
  data class C(...): A
}

fun something(a: A): Int

every { something(any()) } returns 0
every { something(any<B>() } returns 1

I would expect that something(B(...)) would return 1 ✅ correct
And that something(C(...)) would return 0 ❌ wrong

This is because the Type in any<Type>() actually doesn’t “work”.

The correct way to do this is the more verbose one

every { something(any()) } answer {
  when (firstArg<A>()) {
    is B -> 1
    else -> 0 // or error() or whatever
  }
}

Is this expected or is it a bug?
Mock 1.13.2 on JVM 11

[Sam]

Are you looking for ofType<Type>()?

every { something(ofType<B>()) } returns 1

[Sam]

(I agree, it can be confusing that any<Type>() doesn’t actually check the type 😞)

[Davide Giuseppe Farella]

ofType does work! Thank you so much!

[Klitos Kyriacou]

any<Type>() is still useful, though. The explicit generic parameter is required for compile-time overload resolution.