I had some manual serializers written for some Groovy classes of a library. Now this library ported ...

# serialization

[Vampire]

I had some manual serializers written for some Groovy classes of a library.
Now this library ported their code over to Kotlin.
I adapted the serializers to the changes like some new fields on the way and some nullability changes.
But now I get on the @Serializer(forClass = ...) annotations:

Cannot generate external serializer 'FooSerializer': class 'Foo' is defined in another module

😞

Anything I can do about that?

[Adam S]

probably not https://github.com/Kotlin/kotlinx.serialization/issues/532

[Adam S]

how many classes do you want to handle?

[Vampire]

Seven.
But actually it seems to be a false-positive in the IDE.
It actually works fine.

[Vampire]

Maybe because the IDE plugin is 1.8.0 but it is in an 1.7.20 project unless Gradle updates the embedded Kotlin to 1.8

[Vampire]

The issue you link to seems to be unrelated also, it is a completely different message than what IntelliJ says and that also happens with the serializer in the same module and also it is about automatic external serializers while I have a manual custom serializer.

[Vampire]

Ok, forget it, the @Serializer(forClass = ...) annotations were superfluous anyway.
No idea why I added them back then.
But as I do complete manual serializer, they have no effect anyway as far as I understood.
I just removed them and it still works perfectly fine. 🙂

[Vampire]

Thanks for being my rubber duck 🙂

[Vampire]

It's actually this: https://github.com/Kotlin/kotlinx.serialization/issues/2182

[Adam S]

ahh okay, good you found it, and my pleasure rubber duck

[Adam S]

it was this comment that caught my eye in the issue I linked

External automatic serializers generation is in many ways experimental feature for now, and due to its complexity, it has many bugs beside this one.