// CHECK JVM_IR:
//   Mangled name: #test(kotlin.Any?;kotlin.Function3<kotlin.Any,kotlin.Int,kotlin.String,kotlin.Unit>){}kotlin.Unit?
//   Public signature: /test|-6483776340446886488[0]
//   Public signature debug description: test(kotlin.Any?;kotlin.Function3<kotlin.Any,kotlin.Int,kotlin.String,kotlin.Unit>){}kotlin.Unit?
// CHECK JS_IR NATIVE:
//   Mangled name: #test(kotlin.Any?;kotlin.Function3<kotlin.Any,kotlin.Int,kotlin.String,kotlin.Unit>){}
//   Public signature: /test|7562359801694057104[0]
//   Public signature debug description: test(kotlin.Any?;kotlin.Function3<kotlin.Any,kotlin.Int,kotlin.String,kotlin.Unit>){}
fun test(receiver: Any?, fn: @ExtensionFunctionType Function3<Any, Int, String, Unit>): Unit?