[LL API] Provide proper way for automatic registration of compiler plugins

analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/project/structure/sessionFactoryHelpers.kt

@@ -12,10 +12,10 @@ import org.jetbrains.kotlin.analysis.low.level.api.fir.api.services.createSealed
 import org.jetbrains.kotlin.analysis.low.level.api.fir.fir.caches.FirThreadSafeCachesFactory
 import org.jetbrains.kotlin.analysis.low.level.api.fir.providers.LLFirIdePredicateBasedProvider
 import org.jetbrains.kotlin.analysis.low.level.api.fir.providers.LLFirIdeRegisteredPluginAnnotations
-import org.jetbrains.kotlin.analysis.low.level.api.fir.sessions.LLFirLibraryOrLibrarySourceResolvableModuleSession
 import org.jetbrains.kotlin.analysis.low.level.api.fir.sessions.LLFirSession
 import org.jetbrains.kotlin.analysis.low.level.api.fir.sessions.LLFirSourcesSession
 import org.jetbrains.kotlin.analysis.project.structure.KtSourceModule
+import org.jetbrains.kotlin.analysis.project.structure.KtCompilerPluginsProvider
 import org.jetbrains.kotlin.analysis.project.structure.moduleScopeProvider
 import org.jetbrains.kotlin.analysis.providers.createAnnotationResolver
 import org.jetbrains.kotlin.analysis.providers.createDeclarationProvider
@@ -24,6 +24,7 @@ import org.jetbrains.kotlin.fir.SessionConfiguration
 import org.jetbrains.kotlin.fir.caches.FirCachesFactory
 import org.jetbrains.kotlin.fir.declarations.SealedClassInheritorsProvider
 import org.jetbrains.kotlin.fir.extensions.FirExtensionRegistrar
+import org.jetbrains.kotlin.fir.extensions.FirExtensionRegistrarAdapter
 import org.jetbrains.kotlin.fir.extensions.FirPredicateBasedProvider
 import org.jetbrains.kotlin.fir.extensions.FirRegisteredPluginAnnotations
 import org.jetbrains.kotlin.fir.java.FirJavaFacadeForSource
@@ -47,9 +48,15 @@ internal inline fun createCompositeSymbolProvider(
     FirCompositeSymbolProvider(session, buildList(createSubProviders))
 
 @SessionConfiguration
-internal fun FirSession.registerCompilerPluginExtensions(project: Project) {
+internal fun FirSession.registerCompilerPluginExtensions(project: Project, module: KtSourceModule) {
+    val extensionProvider = project.getService(KtCompilerPluginsProvider::class.java) ?: return
     FirSessionFactory.FirSessionConfigurator(this).apply {
-        for (extensionRegistrar in FirExtensionRegistrar.getInstances(project)) {
+        @Suppress("UNCHECKED_CAST")
+        val registrars = extensionProvider.getRegisteredExtensions(
+            module,
+            FirExtensionRegistrarAdapter,
+        ) as List<FirExtensionRegistrar>
+        for (extensionRegistrar in registrars) {
             registerExtensions(extensionRegistrar.configure())
         }
     }.configure()

analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/sessions/LLFirSessionFactory.kt

@@ -97,7 +97,7 @@ internal object LLFirSessionFactory {
             register(FirPhaseManager::class, LLFirPhaseManager(sessionInvalidator))
 
             registerCompilerPluginServices(contentScope, project, module)
-            registerCompilerPluginExtensions(project)
+            registerCompilerPluginExtensions(project, module)
 
             val switchableExtensionDeclarationsSymbolProvider = FirSwitchableExtensionDeclarationsSymbolProvider.create(session)?.also {
                 register(FirSwitchableExtensionDeclarationsSymbolProvider::class, it)
@@ -198,8 +198,6 @@ internal object LLFirSessionFactory {
             register(FirRegisteredPluginAnnotations::class, LLFirIdeRegisteredPluginAnnotations(this@session, annotationsResolver))
             register(FirPredicateBasedProvider::class, FirEmptyPredicateBasedProvider())
 
-            registerCompilerPluginExtensions(project)
-
             val dependencyProvider = LLFirDependentModuleProviders(this) {
                 // <all libraries scope> - <current library scope>
                 val librariesSearchScope =

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/services/KtCompilerPluginsProviderForTests.kt

@@ -0,0 +1,17 @@
+/*
+ * Copyright 2010-2022 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.analysis.low.level.api.fir.services
+
+import com.intellij.openapi.project.Project
+import org.jetbrains.kotlin.analysis.project.structure.KtCompilerPluginsProvider
+import org.jetbrains.kotlin.analysis.project.structure.KtSourceModule
+import org.jetbrains.kotlin.extensions.ProjectExtensionDescriptor
+
+internal class KtCompilerPluginsProviderForTests(val project: Project) : KtCompilerPluginsProvider() {
+    override fun <T : Any> getRegisteredExtensions(module: KtSourceModule, extensionType: ProjectExtensionDescriptor<T>): List<T> {
+        return extensionType.getInstances(project)
+    }
+}

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/test/base/AnalysisApiFirTestServiceRegistrar.kt

@@ -15,8 +15,10 @@ import org.jetbrains.kotlin.analysis.api.fir.KtFirAnalysisSessionProvider
 import org.jetbrains.kotlin.analysis.low.level.api.fir.LLFirResolveSessionService
 import org.jetbrains.kotlin.analysis.low.level.api.fir.api.services.FirSealedClassInheritorsProcessorFactory
 import org.jetbrains.kotlin.analysis.low.level.api.fir.api.services.PackagePartProviderFactory
+import org.jetbrains.kotlin.analysis.low.level.api.fir.services.KtCompilerPluginsProviderForTests
 import org.jetbrains.kotlin.analysis.low.level.api.fir.services.LLFirSealedClassInheritorsProcessorFactoryForTests
 import org.jetbrains.kotlin.analysis.low.level.api.fir.services.PackagePartProviderTestImpl
+import org.jetbrains.kotlin.analysis.project.structure.KtCompilerPluginsProvider
 import org.jetbrains.kotlin.analysis.test.framework.test.configurators.AnalysisApiTestServiceRegistrar
 import org.jetbrains.kotlin.asJava.KotlinAsJavaSupport
 import org.jetbrains.kotlin.asJava.finder.JavaElementFinder
@@ -46,6 +48,7 @@ object AnalysisApiFirTestServiceRegistrar : AnalysisApiTestServiceRegistrar() {
 
             registerService(SymbolLightClassFacadeCache::class.java)
             registerService(KotlinAsJavaSupport::class.java, KotlinAsJavaFirSupport(project))
+            registerService(KtCompilerPluginsProvider::class.java, KtCompilerPluginsProviderForTests(project))
         }
 
         with(PsiElementFinder.EP.getPoint(project)) {

analysis/project-structure/src/org/jetbrains/kotlin/analysis/project/structure/KtCompilerPluginsProvider.kt

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2010-2022 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.analysis.project.structure
+
+import org.jetbrains.kotlin.extensions.ProjectExtensionDescriptor
+
+/**
+ * A service which can return extensions which are registered for some module
+ */
+public abstract class KtCompilerPluginsProvider {
+    /**
+     * Returns a list of extensions of a base [extensionType] which are registered for [module]
+     */
+    public abstract fun <T : Any> getRegisteredExtensions(module: KtSourceModule, extensionType: ProjectExtensionDescriptor<T>): List<T>
+}