I've got a `sealed class` I'm checking for with a `when` and a lot of branches checking for the spec...

# compiler

[reactormonk]

I've got a sealed class I'm checking for with a when and a lot of branches checking for the specific subtypes via is Type.SubType - how can I force a completeness check?

[Vampire]

Is it not?

[dmitriy.novozhilov]

When expressions and statements with enum/sealed type/boolean in subject are required to be exhaustive by default since Kotlin 1.6
https://kotlinlang.org/docs/whatsnew16.html#stable-exhaustive-when-statements-for-enum-sealed-and-boolean-subjects

[Vampire]

I think since 1.6.0 it should give a warning and fail since 1.7.0: https://kotlinlang.org/docs/whatsnew16.html#stable-exhaustive-when-statements-for-enum-sealed-and-boolean-subjects

[reactormonk]

That's weird, it compiles just fine

[reactormonk]

when (cardMessage) {
            is CardMessage.Accept -> onNewDesiredState(DesiredState.AcceptCall)
            is CardMessage.Reject -> onNewDesiredState(DesiredState.RejectCall)
        }

And the class:

@Parcelize sealed class CardMessage : Parcelable {
    @Parcelize sealed class RssSeries(val url: Uri): CardMessage()
    @Parcelize object Accept: Command() {
        override fun toString(): String {
            return "Accept()"
        }
    }
    @Parcelize object Reject: Command() {
        override fun toString(): String {
            return "Reject()"
        }
    }
}

[christophsturm]

what checks are missing?

[Vampire]

Command maybe?

[christophsturm]

Command is sealed so its abstract

[Vampire]

Ah, right, then I also don't see what could be missing 🙂

[reactormonk]

Ah, bad example then, I shortened it a bit too much.

[reactormonk]

Replaced Command with RssSeries

[christophsturm]

ok but its still abstract

[reactormonk]

Oh, that explains it 🤦

[Vampire]

https://play.kotlinlang.org/#eyJ2ZXJzaW9uIjoiMS44LjIxIiwicGxhdGZvcm0iOiJqYXZhIiwiYXJncy[…]MgQ2FyZE1lc3NhZ2UuUmVqZWN0IC0+IFVuaXRcbiAgICB9XG59XG4ifQ==

[Vampire]

'when' expression must be exhaustive, add necessary 'Maybe' branch or 'else' branch instead