As part of implementing K2 support in a compiler p...

# k2-adopters

[Claus Rørbech]

As part of implementing K2 support in a compiler plugin that generates a Companion object I get the following error when combining the plugin with kotlinx.serialization.

java.lang.IllegalStateException: Multiple plugins generated nested class with same name Companion for class /Sample:
public final companion object Companion : R|kotlin/Any| {
}

public final companion object Companion : R|kotlin/Any| {
}

Seems like both plugins are generating a Companion. For user-defined companions the FirRegularClassSymbol.companionObjectSymbol will be non-null, but I have tried debugging and cannot find any information to indentify and prevent this situation in my FirDeclarationGenerationExtension.getNestedClassifiersNames and/or FirDeclarationGenerationExtension.generateNestedClassLikeDeclaration. Also tried debugging the kotlinx.serialization-plugin and there is also no visibility of my generated companion, so does not look like an ordering issue and even with both plugins setting their appropriate GeneratedDeclarationKey there is no way to detect each others additions. Anybody with a suggestion to identify this situation, or how are plugins supposed to coexist?

[dmitriy.novozhilov]

Hey
Such plugins interaction actually just want considered when API was designed
Could you please report an issue?

[dmitriy.novozhilov]

I'm not sure that it can be fixed in the nearest future
As a workaround I can suggest to temporary force to declare empty companion for classes with such clashes

[Claus Rørbech]

I have created this youtrack issue

[dmitriy.novozhilov]

Thank you!