java.lang.IllegalStateException: unhandled value type on Multiplatform/JS target

[mikedawson]

I have an annotation processor that uses Kotlin multiplatform for Android, JVM, and JS targets. Everything was working fine with Kotlin 1.8.10 KSP 1.0.9 . Now using Kotlin 1.9 KSP 1.0.13 results has an exception as follows:

e: [ksp] java.lang.IllegalStateException: unhandled value type, please file a bug at https://github.com/google/ksp/issues/new
        at com.google.devtools.ksp.UtilsKt.createInvocationHandler$lambda$8(utils.kt:381)
        at jdk.proxy12/jdk.proxy12.$Proxy229.indices(Unknown Source)
        at com.ustadmobile.lib.annotationprocessor.core.CodeBlockExtKt.addCreateTableCode(CodeBlockExt.kt:74)

To reproduce:

1. Checkout the project from https://github.com/UstadMobile/door/
2. Checkout the kotlin1.9 branch or commit 9dc3e5487f6b280cd48f163c3e601a35f3b73251
3. Run the Gradle task gradlew door-testdb:jsJar

It is throwing an exception when running the getAnnotation function. The exception itself is coming from here in utils.kt:

// Workaround for java annotation value array type
                        // https://github.com/google/ksp/issues/1329
                        method.returnType.isArray -> {
                            if (result !is Array<*>) {
                                val value = { result.asArray(method, clazz) }
                                cache.getOrPut(Pair(method.returnType, value), value)
                            } else {
                                throw IllegalStateException("unhandled value type, $ExceptionMessage")
                            }
                        }

Would appreciate to know if there any fix / workaround: this is a blocker to prevent me from being able to update to Kotlin 1.9.

[mikedawson]

The Exception is coming from the proxy which is returned by KSAnnotated.getAnnotation(class). The workaround I am using for now is to use KSAnnotation itself and "manually" instantiate the annotation class.

fun KSAnnotation.toMyAnnotation(): MyAnnotation {
   if(annotationType.resolve().declaration.qualifiedName?.asString() != "mypackage.MyAnnotation") 
     throw IllegalArgumentException("not a myannotation!")

   return MyAnnotation(
      name = arguments.firstOrNull { it.name?.asString() == "name" }?.value as? String
   )
}

KSValueArgument.value is not really typed: it's Any. Different parameter types (e.g. Enums, String arrays, Class arrays, etc) have different types. You can use the debugger to inspect and figure it out.