Hello everyone!, I was looking at

org.jetbrains.kotlin.fir.extensions.FirExtensionRegistrar

and looking into how to integrate with plugins that depend on

org.jetbrains.kotlin.compiler.plugin.ComponentRegistrar

and

org.jetbrains.kotlin.compiler.plugin.CommandLineProcessor

. I see

AllOpen

and others are connected to the new FIR frontend and I was hoping to run some compiler plugin tests and work on the FIR support for arrow meta. I have a couple of questions that came up while I was working on this. Here it goes in case anyone can help. 1. The

FirExtensionRegistrar

unlike the

ComponentRegistrar

is not an interface but an abstract class and it requires a separate lifecycle. Once instantiated for regular CLI plugins and another for the FIR style of subscription. Did I miss-understood this or is there a way to integrate this with existing compiler plugins based on the

ComponentRegistrar

? 2. Even when declaring both of those extensions and enabling FIR with

configuration.put(CommonConfigurationKeys.USE_FIR, true)

the override for the FIR plugin`override fun ExtensionRegistrarContext.configurePlugin(): Unit` never gets called, Is there something else needed to enable FIR beside that flag? If anyone has had success testing the FIR extension points or could provide any guidance or example as to how to enable them I’d very much appreciate it. Thanks!

Hi Raul

FirExtensionRegistrar

and corresponding infrastructure is a PoC prototype which we implemented a year ago. Currently there is no API for FIR compiler plugins. All FirExtensions you may find in project didn't work at all and will be changed in future, so it's meaningless to try to implement something with them

Thanks so much @dmitriy.novozhilov and this clarifies it. I was thinking while I wait for the compiler extensions for FIR to make it that maybe I could bootstrap the FIR process in

AnalysisExtension.doAnalysis

method to send all the KtFiles to Fir. If you have any pointers to code anywhere to launch FIR from analysis or other part that would make sense that may help. Thanks!

Do you interested in FIR research running compiler on small tests or on some real projects? Or maybe both?

yes to all 🙂

Ok, I will write some doc today or tomorrow

thank you so much, appreciate your time and help 🙏