[FIR] Make FirExtensionRegistrar a proper extension point

After that commit it's allowed to register any FIR plugin using
  existing extension infrastructure (`-Xplugin` CLI argument,
  plugin.xml for IDE plugins, etc)

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

@@ -28,6 +28,7 @@ import org.jetbrains.kotlin.fir.caches.FirCachesFactory
 import org.jetbrains.kotlin.fir.checkers.registerExtendedCommonCheckers
 import org.jetbrains.kotlin.fir.declarations.SealedClassInheritorsProvider
 import org.jetbrains.kotlin.fir.deserialization.ModuleDataProvider
+import org.jetbrains.kotlin.fir.extensions.FirExtensionRegistrar
 import org.jetbrains.kotlin.fir.java.FirJavaFacade
 import org.jetbrains.kotlin.fir.java.JavaSymbolProvider
 import org.jetbrains.kotlin.fir.java.deserialization.JvmClassFileBasedSymbolProvider
@@ -159,6 +160,9 @@ internal object FirIdeSessionFactory {
                 if (isRootModule) {
                     registerExtendedCommonCheckers()
                 }
+                for (extensionRegistrar in FirExtensionRegistrar.getInstances(project)) {
+                    registerExtensions(extensionRegistrar.configure())
+                }
             }.configure()
             configureSession?.invoke(this)
         }

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/FirKotlinToJvmBytecodeCompiler.kt

@@ -32,6 +32,7 @@ import org.jetbrains.kotlin.fir.backend.jvm.FirJvmBackendExtension
 import org.jetbrains.kotlin.fir.checkers.registerExtendedCommonCheckers
 import org.jetbrains.kotlin.fir.declarations.FirFile
 import org.jetbrains.kotlin.fir.declarations.FirSimpleFunction
+import org.jetbrains.kotlin.fir.extensions.FirExtensionRegistrar
 import org.jetbrains.kotlin.fir.java.FirProjectSessionProvider
 import org.jetbrains.kotlin.fir.pipeline.buildFirFromKtFiles
 import org.jetbrains.kotlin.fir.pipeline.convertToIr
@@ -87,6 +88,7 @@ object FirKotlinToJvmBytecodeCompiler {
         val isMultiModuleChunk = chunk.size > 1
 
         // TODO: run lowerings for all modules in the chunk, then run codegen for all modules.
+        val project = (projectEnvironment as? PsiBasedProjectEnvironment)?.project
         for (module in chunk) {
             val moduleConfiguration = projectConfiguration.applyModuleProperties(module, buildFile)
             val context = CompilationContext(
@@ -101,7 +103,8 @@ object FirKotlinToJvmBytecodeCompiler {
                 targetIds,
                 incrementalComponents,
                 extendedAnalysisMode,
-                (projectEnvironment as? PsiBasedProjectEnvironment)?.project?.let { IrGenerationExtension.getInstances(it) } ?: emptyList()
+                firExtensionRegistrars = project?.let { FirExtensionRegistrar.getInstances(it) } ?: emptyList(),
+                irGenerationExtensions = project?.let { IrGenerationExtension.getInstances(it) } ?: emptyList()
             )
             val generationState = context.compileModule() ?: return false
             outputs += generationState
@@ -112,7 +115,7 @@ object FirKotlinToJvmBytecodeCompiler {
         }
 
         return writeOutputs(
-            (projectEnvironment as? PsiBasedProjectEnvironment)?.project,
+            project,
             projectConfiguration,
             chunk,
             outputs.map(Pair<FirResult, GenerationState>::second),
@@ -208,6 +211,7 @@ object FirKotlinToJvmBytecodeCompiler {
                 librariesScope,
                 lookupTracker = moduleConfiguration.get(CommonConfigurationKeys.LOOKUP_TRACKER),
                 providerAndScopeForIncrementalCompilation,
+                firExtensionRegistrars,
                 dependenciesConfigurator = {
                     dependencies(moduleConfiguration.jvmClasspathRoots.map { it.toPath() })
                     dependencies(moduleConfiguration.jvmModularRoots.map { it.toPath() })
@@ -350,6 +354,7 @@ object FirKotlinToJvmBytecodeCompiler {
         val targetIds: List<TargetId>?,
         val incrementalComponents: IncrementalCompilationComponents?,
         val extendedAnalysisMode: Boolean,
+        val firExtensionRegistrars: List<FirExtensionRegistrar>,
         val irGenerationExtensions: Collection<IrGenerationExtension>
     )
 

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/KotlinCoreEnvironment.kt

@@ -82,6 +82,7 @@ import org.jetbrains.kotlin.config.*
 import org.jetbrains.kotlin.extensions.*
 import org.jetbrains.kotlin.extensions.internal.CandidateInterceptor
 import org.jetbrains.kotlin.extensions.internal.TypeResolutionInterceptor
+import org.jetbrains.kotlin.fir.extensions.FirExtensionRegistrar
 import org.jetbrains.kotlin.idea.KotlinFileType
 import org.jetbrains.kotlin.js.translate.extensions.JsSyntheticTranslateExtension
 import org.jetbrains.kotlin.load.kotlin.KotlinBinaryClassCache
@@ -648,6 +649,7 @@ class KotlinCoreEnvironment private constructor(
             TypeResolutionInterceptor.registerExtensionPoint(project)
             CandidateInterceptor.registerExtensionPoint(project)
             DescriptorSerializerPlugin.registerExtensionPoint(project)
+            FirExtensionRegistrar.registerExtensionPoint(project)
         }
 
         internal fun registerExtensionsFromPlugins(project: MockProject, configuration: CompilerConfiguration) {

compiler/fir/entrypoint/src/org/jetbrains/kotlin/fir/extensions/FirExtensionRegistrar.kt

@@ -5,14 +5,18 @@
 
 package org.jetbrains.kotlin.fir.extensions
 
+import org.jetbrains.kotlin.extensions.ProjectExtensionDescriptor
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.SessionConfiguration
 import org.jetbrains.kotlin.fir.analysis.extensions.FirAdditionalCheckersExtension
 import kotlin.reflect.KClass
 
 abstract class FirExtensionRegistrar {
-    companion object {
+    companion object : ProjectExtensionDescriptor<FirExtensionRegistrar>(
-        val AVAILABLE_EXTENSIONS = listOf(
+        name = "org.jetbrains.kotlin.fir.extensions.firExtensionRegistrar",
+        extensionClass = FirExtensionRegistrar::class.java
+    ) {
+        internal val AVAILABLE_EXTENSIONS = listOf(
             FirStatusTransformerExtension::class,
             FirDeclarationGenerationExtension::class,
             FirAdditionalCheckersExtension::class,

compiler/fir/entrypoint/src/org/jetbrains/kotlin/fir/session/FirSessionFactory.kt

@@ -84,6 +84,7 @@ object FirSessionFactory {
         librariesScope: AbstractProjectFileSearchScope,
         lookupTracker: LookupTracker?,
         providerAndScopeForIncrementalCompilation: ProviderAndScopeForIncrementalCompilation?,
+        extensionRegistrars: List<FirExtensionRegistrar>,
         dependenciesConfigurator: DependencyListForCliModule.Builder.() -> Unit = {},
         noinline sessionConfigurator: FirSessionConfigurator.() -> Unit = {},
     ): FirSession {
@@ -113,6 +114,7 @@ object FirSessionFactory {
             sourceScope,
             projectEnvironment,
             providerAndScopeForIncrementalCompilation,
+            extensionRegistrars,
             languageVersionSettings = languageVersionSettings,
             lookupTracker = lookupTracker,
             init = sessionConfigurator
@@ -125,6 +127,7 @@ object FirSessionFactory {
         scope: AbstractProjectFileSearchScope,
         projectEnvironment: AbstractProjectEnvironment,
         providerAndScopeForIncrementalCompilation: ProviderAndScopeForIncrementalCompilation?,
+        extensionRegistrars: List<FirExtensionRegistrar>,
         languageVersionSettings: LanguageVersionSettings = LanguageVersionSettingsImpl.DEFAULT,
         lookupTracker: LookupTracker? = null,
         init: FirSessionConfigurator.() -> Unit = {}
@@ -160,6 +163,9 @@ object FirSessionFactory {
             FirSessionConfigurator(this).apply {
                 registerCommonCheckers()
                 registerJvmCheckers()
+                for (extensionRegistrar in extensionRegistrars) {
+                    registerExtensions(extensionRegistrar.configure())
+                }
                 init()
             }.configure()
 

compiler/tests-common-new/tests/org/jetbrains/kotlin/test/frontend/fir/FirFrontendFacade.kt

@@ -20,6 +20,7 @@ import org.jetbrains.kotlin.cli.jvm.config.jvmModularRoots
 import org.jetbrains.kotlin.config.JVMConfigurationKeys
 import org.jetbrains.kotlin.fir.analysis.FirAnalyzerFacade
 import org.jetbrains.kotlin.fir.checkers.registerExtendedCommonCheckers
+import org.jetbrains.kotlin.fir.extensions.FirExtensionRegistrar
 import org.jetbrains.kotlin.fir.moduleData
 import org.jetbrains.kotlin.fir.session.FirSessionFactory
 import org.jetbrains.kotlin.js.resolve.JsPlatformAnalyzerServices
@@ -91,6 +92,7 @@ class FirFrontendFacade(
             PsiBasedProjectFileSearchScope(librariesScope),
             lookupTracker = null,
             providerAndScopeForIncrementalCompilation = null,
+            extensionRegistrars = FirExtensionRegistrar.getInstances(project),
             dependenciesConfigurator = {
                 dependencies(configuration.jvmModularRoots.map { it.toPath() })
                 dependencies(configuration.jvmClasspathRoots.map { it.toPath() })

compiler/tests-common/tests/org/jetbrains/kotlin/fir/AbstractFirBaseDiagnosticsTest.kt

@@ -98,6 +98,7 @@ abstract class AbstractFirBaseDiagnosticsTest : BaseDiagnosticsTest() {
                 librariesScope = PsiBasedProjectFileSearchScope(allProjectScope),
                 lookupTracker = null,
                 providerAndScopeForIncrementalCompilation = null,
+                extensionRegistrars = emptyList()
             ) {
                 configureSession()
                 getFirExtensions()?.let {

compiler/tests-compiler-utils/tests/org/jetbrains/kotlin/fir/SessionTestUtils.kt

@@ -40,6 +40,7 @@ fun createSessionForTests(
     librariesScope,
     lookupTracker = null,
     providerAndScopeForIncrementalCompilation = null,
+    extensionRegistrars = emptyList(),
     dependenciesConfigurator = {
         friendDependencies(friendsPaths)
     }
@@ -65,6 +66,7 @@ fun createSessionForTests(
         PsiBasedProjectFileSearchScope(librariesScope),
         lookupTracker = null,
         providerAndScopeForIncrementalCompilation = null,
+        extensionRegistrars = emptyList(),
         dependenciesConfigurator = {
             friendDependencies(friendsPaths)
         }

plugins/fir/fir-plugin-prototype/tests/org/jetbrains/kotlin/fir/plugin/runners/commonPluginTestConfiguration.kt

@@ -5,18 +5,15 @@
 
 package org.jetbrains.kotlin.fir.plugin.runners
 
-import org.jetbrains.kotlin.fir.plugin.FirAllOpenComponentRegistrar
+import org.jetbrains.kotlin.fir.plugin.services.ExtensionRegistrarConfigurator
-import org.jetbrains.kotlin.fir.plugin.services.IrExtensionRegistrar
 import org.jetbrains.kotlin.fir.plugin.services.PluginAnnotationsProvider
-import org.jetbrains.kotlin.test.Constructor
 import org.jetbrains.kotlin.test.builders.TestConfigurationBuilder
 import org.jetbrains.kotlin.test.directives.FirDiagnosticsDirectives.ENABLE_PLUGIN_PHASES
 import org.jetbrains.kotlin.test.directives.FirDiagnosticsDirectives.FIR_DUMP
-import org.jetbrains.kotlin.test.frontend.fir.FirFrontendFacade
 import org.jetbrains.kotlin.test.runners.baseFirDiagnosticTestConfiguration
 
 fun TestConfigurationBuilder.commonFirWithPluginFrontendConfiguration() {
-    baseFirDiagnosticTestConfiguration(frontendFacade = FirFrontendFacadeWithPlugin)
+    baseFirDiagnosticTestConfiguration()
 
     defaultDirectives {
         +ENABLE_PLUGIN_PHASES
@@ -25,13 +22,6 @@ fun TestConfigurationBuilder.commonFirWithPluginFrontendConfiguration() {
 
     useConfigurators(
         ::PluginAnnotationsProvider,
-        ::IrExtensionRegistrar
+        ::ExtensionRegistrarConfigurator
     )
 }
-
-val FirFrontendFacadeWithPlugin: Constructor<FirFrontendFacade>
-    get() = { testServices ->
-        FirFrontendFacade(testServices) {
-            it.registerExtensions(FirAllOpenComponentRegistrar().configure())
-        }
-    }

plugins/fir/fir-plugin-prototype/tests/org/jetbrains/kotlin/fir/plugin/services/ExtensionRegistrarConfigurator.kt

@@ -7,12 +7,15 @@ package org.jetbrains.kotlin.fir.plugin.services
 
 import com.intellij.openapi.project.Project
 import org.jetbrains.kotlin.backend.common.extensions.IrGenerationExtension
+import org.jetbrains.kotlin.fir.extensions.FirExtensionRegistrar
+import org.jetbrains.kotlin.fir.plugin.FirAllOpenComponentRegistrar
 import org.jetbrains.kotlin.ir.plugin.GeneratedDeclarationsIrBodyFiller
 import org.jetbrains.kotlin.test.services.EnvironmentConfigurator
 import org.jetbrains.kotlin.test.services.TestServices
 
-class IrExtensionRegistrar(testServices: TestServices) : EnvironmentConfigurator(testServices) {
+class ExtensionRegistrarConfigurator(testServices: TestServices) : EnvironmentConfigurator(testServices) {
     override fun registerCompilerExtensions(project: Project) {
+        FirExtensionRegistrar.registerExtension(project, FirAllOpenComponentRegistrar())
         IrGenerationExtension.registerExtension(project, GeneratedDeclarationsIrBodyFiller())
     }
 }

plugins/parcelize/parcelize-compiler/tests/org/jetbrains/kotlin/parcelize/test/runners/AbstractFirParcelizeDiagnosticTest.kt

@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.parcelize.test.runners
 
-import org.jetbrains.kotlin.parcelize.test.services.FirFacadeWithParcelizeExtension
 import org.jetbrains.kotlin.parcelize.test.services.ParcelizeEnvironmentConfigurator
 import org.jetbrains.kotlin.test.bind
 import org.jetbrains.kotlin.test.builders.TestConfigurationBuilder
@@ -18,7 +17,7 @@ import org.jetbrains.kotlin.test.services.fir.FirOldFrontendMetaConfigurator
 
 abstract class AbstractFirParcelizeDiagnosticTest : AbstractKotlinCompilerTest() {
     override fun TestConfigurationBuilder.configuration() {
-        baseFirDiagnosticTestConfiguration(frontendFacade = FirFacadeWithParcelizeExtension)
+        baseFirDiagnosticTestConfiguration()
 
         defaultDirectives {
             +FirDiagnosticsDirectives.ENABLE_PLUGIN_PHASES

plugins/parcelize/parcelize-compiler/tests/org/jetbrains/kotlin/parcelize/test/runners/AbstractParcelizeBoxTest.kt

@@ -17,7 +17,6 @@ import org.jetbrains.kotlin.test.backend.ir.JvmIrBackendFacade
 import org.jetbrains.kotlin.test.bind
 import org.jetbrains.kotlin.test.builders.*
 import org.jetbrains.kotlin.test.directives.CodegenTestDirectives.REQUIRES_SEPARATE_PROCESS
-import org.jetbrains.kotlin.test.directives.DiagnosticsDirectives.DIAGNOSTICS
 import org.jetbrains.kotlin.test.directives.DiagnosticsDirectives.REPORT_ONLY_EXPLICITLY_DEFINED_DEBUG_INFO
 import org.jetbrains.kotlin.test.directives.FirDiagnosticsDirectives.ENABLE_PLUGIN_PHASES
 import org.jetbrains.kotlin.test.frontend.classic.ClassicFrontend2ClassicBackendConverter
@@ -26,6 +25,7 @@ import org.jetbrains.kotlin.test.frontend.classic.ClassicFrontendFacade
 import org.jetbrains.kotlin.test.frontend.classic.ClassicFrontendOutputArtifact
 import org.jetbrains.kotlin.test.frontend.classic.handlers.ClassicDiagnosticsHandler
 import org.jetbrains.kotlin.test.frontend.fir.Fir2IrResultsConverter
+import org.jetbrains.kotlin.test.frontend.fir.FirFrontendFacade
 import org.jetbrains.kotlin.test.frontend.fir.FirOutputArtifact
 import org.jetbrains.kotlin.test.frontend.fir.handlers.FirDiagnosticsHandler
 import org.jetbrains.kotlin.test.model.*
@@ -116,7 +116,7 @@ open class AbstractParcelizeFirBoxTest : AbstractParcelizeBoxTestBase<FirOutputA
     TargetBackend.JVM_IR
 ) {
     override val frontendFacade: Constructor<FrontendFacade<FirOutputArtifact>>
-        get() = FirFacadeWithParcelizeExtension
+        get() = ::FirFrontendFacade
 
     override val frontendToBackendConverter: Constructor<Frontend2BackendConverter<FirOutputArtifact, IrBackendInput>>
         get() = ::Fir2IrResultsConverter

plugins/parcelize/parcelize-compiler/tests/org/jetbrains/kotlin/parcelize/test/services/FirFacadeWithParcelizeExtension.kt

@@ -1,16 +0,0 @@
-/*
- * Copyright 2010-2021 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.parcelize.test.services
-
-import org.jetbrains.kotlin.parcelize.fir.FirParcelizeExtensionRegistrar
-import org.jetbrains.kotlin.test.Constructor
-import org.jetbrains.kotlin.test.frontend.fir.FirFrontendFacade
-
-val FirFacadeWithParcelizeExtension: Constructor<FirFrontendFacade> = { testServices ->
-    FirFrontendFacade(testServices) {
-        it.registerExtensions(FirParcelizeExtensionRegistrar().configure())
-    }
-}

plugins/parcelize/parcelize-compiler/tests/org/jetbrains/kotlin/parcelize/test/services/ParcelizeEnvironmentConfigurator.kt

@@ -9,8 +9,10 @@ import com.intellij.openapi.project.Project
 import org.jetbrains.kotlin.backend.common.extensions.IrGenerationExtension
 import org.jetbrains.kotlin.cli.jvm.config.addJvmClasspathRoots
 import org.jetbrains.kotlin.config.CompilerConfiguration
+import org.jetbrains.kotlin.fir.extensions.FirExtensionRegistrar
 import org.jetbrains.kotlin.parcelize.ParcelizeComponentRegistrar
 import org.jetbrains.kotlin.parcelize.ParcelizeFirIrGeneratorExtension
+import org.jetbrains.kotlin.parcelize.fir.FirParcelizeExtensionRegistrar
 import org.jetbrains.kotlin.test.model.TestModule
 import org.jetbrains.kotlin.test.services.EnvironmentConfigurator
 import org.jetbrains.kotlin.test.services.TestServices
@@ -31,6 +33,7 @@ class ParcelizeEnvironmentConfigurator(
 
     override fun registerCompilerExtensions(project: Project) {
         if (useFirExtension) {
+            FirExtensionRegistrar.registerExtension(project, FirParcelizeExtensionRegistrar())
             IrGenerationExtension.registerExtension(project, ParcelizeFirIrGeneratorExtension())
         } else {
             ParcelizeComponentRegistrar.registerParcelizeComponents(project)