Using Kotlin extension functions in Resolvers

[roschlau]

I'm using the graphql tools from Kotlin, and I would love to use extension functions in my resolver classes for readability:

package some.package

class Service(
    val name: String,
    val url: String
)

class ServiceResolver() : GraphQLResolver<Service> {
    fun Service.healthy() = TODO("Check $url/health for 200 response")
}

From my experience with Kotlin, the extension function there should have exactly the same bytecode signature as a normal function with a Service object as the first parameter, however, loading the schema fails with a FieldResolverError, stating that a function with the signature of some.package.ServiceResolver.version(some.package.Service) can't be found.

This code worked before, when I was using com.graphql-java:graphql-java-tools:5.2.0, but after updating to version 5.6.0 that's now located in the com.graphql-java-kickstart group, I have to rewrite all extension functions like this to regular functions accepting a parameter to get it working again. Is there anyway using extension functions could be supported again?