FIR IDE: introduce fir lower level module

generators/build.gradle.kts

@@ -39,6 +39,7 @@ dependencies {
     testCompile(projectTests(":idea:idea-maven"))
     testCompile(projectTests(":idea:idea-fir"))
     testCompile(projectTests(":idea:idea-frontend-fir"))
+    testCompile(projectTests(":idea:idea-frontend-fir:idea-fir-low-level-api"))
     testCompile(projectTests(":j2k"))
     testCompile(projectTests(":nj2k"))
     if (Ide.IJ()) {

generators/tests/org/jetbrains/kotlin/generators/tests/GenerateTests.kt

@@ -83,8 +83,8 @@ import org.jetbrains.kotlin.idea.editor.AbstractMultiLineStringIndentTest
 import org.jetbrains.kotlin.idea.editor.backspaceHandler.AbstractBackspaceHandlerTest
 import org.jetbrains.kotlin.idea.editor.quickDoc.AbstractQuickDocProviderTest
 import org.jetbrains.kotlin.idea.filters.AbstractKotlinExceptionFilterTest
-import org.jetbrains.kotlin.idea.fir.AbstractFirLazyResolveTest
+import org.jetbrains.kotlin.idea.fir.low.level.api.AbstractFirLazyResolveTest
-import org.jetbrains.kotlin.idea.fir.AbstractFirMultiModuleResolveTest
+import org.jetbrains.kotlin.idea.fir.low.level.api.AbstractFirMultiModuleResolveTest
 import org.jetbrains.kotlin.idea.fir.AbstractKtDeclarationAndFirDeclarationEqualityChecker
 import org.jetbrains.kotlin.idea.folding.AbstractKotlinFoldingTest
 import org.jetbrains.kotlin.idea.hierarchy.AbstractHierarchyTest

idea/idea-fir/tests/org/jetbrains/kotlin/checkers/AbstractFirPsiCheckerTest.kt

@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.checkers
 
 import com.intellij.rt.execution.junit.FileComparisonFailure
-import org.jetbrains.kotlin.idea.fir.FirResolution
 import org.jetbrains.kotlin.idea.test.withCustomCompilerOptions
 import org.jetbrains.kotlin.test.InTextDirectivesUtils
 import java.io.File

idea/idea-fir/tests/org/jetbrains/kotlin/idea/resolve/AbstractFirReferenceResolveTest.kt

@@ -5,12 +5,10 @@
 
 package org.jetbrains.kotlin.idea.resolve
 
-import com.intellij.testFramework.LightProjectDescriptor
 import org.jetbrains.kotlin.idea.completion.test.configureWithExtraFile
-import org.jetbrains.kotlin.idea.fir.FirResolution
+import org.jetbrains.kotlin.idea.fir.low.level.api.FirResolution
 import org.jetbrains.kotlin.idea.test.KotlinLightProjectDescriptor
 import org.jetbrains.kotlin.idea.test.KotlinWithJdkAndRuntimeLightProjectDescriptor
-import org.jetbrains.kotlin.idea.test.ProjectDescriptorWithStdlibSources
 import org.jetbrains.kotlin.test.InTextDirectivesUtils
 
 abstract class AbstractFirReferenceResolveTest : AbstractReferenceResolveTest() {

idea/idea-frontend-fir/build.gradle.kts

@@ -13,6 +13,7 @@ dependencies {
     compile(project(":compiler:fir:checkers"))
     compile(project(":compiler:fir:java"))
     compile(project(":compiler:fir:jvm"))
+    compile(project(":idea:idea-frontend-fir:idea-fir-low-level-api"))
     compile(intellijDep())
     compile(intellijCoreDep())
 

idea/idea-frontend-fir/idea-fir-low-level-api/build.gradle.kts

@@ -0,0 +1,48 @@
+plugins {
+    kotlin("jvm")
+    id("jps-compatible")
+}
+
+dependencies {
+    compile(project(":compiler:psi"))
+    compile(project(":idea:idea-frontend-independent"))
+    compile(project(":idea:idea-frontend-api"))
+    compile(project(":idea:idea-core"))
+    compile(project(":compiler:fir:fir2ir"))
+    compile(project(":compiler:fir:resolve"))
+    compile(project(":compiler:fir:checkers"))
+    compile(project(":compiler:fir:java"))
+    compile(project(":compiler:fir:jvm"))
+    compile(intellijDep())
+    compile(intellijCoreDep())
+
+// <temp>
+    compile(project(":idea:idea-core"))
+// </temp>
+
+    testCompile(toolsJar())
+    testCompile(projectTests(":idea"))
+    testCompile(projectTests(":compiler:tests-common"))
+    testCompile(projectTests(":idea:idea-test-framework"))
+    testCompile(project(":kotlin-test:kotlin-test-junit"))
+    testCompile(commonDep("junit:junit"))
+
+    Platform[192].orHigher {
+        compile(intellijPluginDep("java"))
+    }
+}
+
+sourceSets {
+    "main" { projectDefault() }
+    "test" { projectDefault() }
+}
+
+if (rootProject.findProperty("idea.fir.plugin") == "true")  {
+    projectTest {
+        dependsOn(":dist")
+        workingDir = rootDir
+    }
+}
+
+testsJar()
+

idea/idea-frontend-fir/idea-fir-low-level-api/src/org/jetbrains/kotlin/idea/fir/low/level/api/FirIdeDiagnosticsCollector.kt

@@ -3,7 +3,7 @@
  * 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.idea.fir
+package org.jetbrains.kotlin.idea.fir.low.level.api
 
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.analysis.collectors.AbstractDiagnosticCollector
@@ -13,7 +13,7 @@ import org.jetbrains.kotlin.fir.analysis.diagnostics.FirDiagnostic
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirPsiDiagnostic
 import org.jetbrains.kotlin.psi.KtElement
 
-class FirIdeDiagnosticsCollector(session: FirSession, private val resolveState: FirModuleResolveState) : AbstractDiagnosticCollector(session) {
+internal class FirIdeDiagnosticsCollector(session: FirSession, private val resolveState: FirModuleResolveState) : AbstractDiagnosticCollector(session) {
 
     init {
         registerAllComponents()

idea/idea-frontend-fir/idea-fir-low-level-api/src/org/jetbrains/kotlin/idea/fir/low/level/api/FirIdeJavaModuleBasedSession.kt

@@ -3,7 +3,7 @@
  * 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.idea.fir
+package org.jetbrains.kotlin.idea.fir.low.level.api
 
 import com.intellij.openapi.project.Project
 import com.intellij.psi.search.GlobalSearchScope
@@ -23,7 +23,7 @@ import org.jetbrains.kotlin.fir.resolve.scopes.wrapScopeWithJvmMapped
 import org.jetbrains.kotlin.fir.scopes.KotlinScopeProvider
 
 
-class FirIdeJavaModuleBasedSession(
+internal class FirIdeJavaModuleBasedSession(
     moduleInfo: ModuleInfo,
     sessionProvider: FirProjectSessionProvider
 ) : FirModuleBasedSession(moduleInfo, sessionProvider) {

idea/idea-frontend-fir/idea-fir-low-level-api/src/org/jetbrains/kotlin/idea/fir/low/level/api/FirIdeModuleDependenciesSymbolProvider.kt

@@ -3,7 +3,7 @@
  * 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.idea.fir
+package org.jetbrains.kotlin.idea.fir.low.level.api
 
 import org.jetbrains.kotlin.fir.resolve.providers.FirSymbolProvider
 import org.jetbrains.kotlin.fir.resolve.providers.impl.FirDependenciesSymbolProviderImpl
@@ -17,7 +17,7 @@ import org.jetbrains.kotlin.idea.caches.project.isLibraryClasses
 import org.jetbrains.kotlin.idea.caches.resolve.IDEPackagePartProvider
 
 
-class FirIdeModuleDependenciesSymbolProvider(
+internal class FirIdeModuleDependenciesSymbolProvider(
     session: FirIdeJavaModuleBasedSession
 ) : FirDependenciesSymbolProviderImpl(session) {
 

idea/idea-frontend-fir/idea-fir-low-level-api/src/org/jetbrains/kotlin/idea/fir/low/level/api/FirIdeProvider.kt

@@ -3,7 +3,7 @@
  * 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.idea.fir
+package org.jetbrains.kotlin.idea.fir.low.level.api
 
 import com.intellij.openapi.progress.ProcessCanceledException
 import com.intellij.openapi.project.Project
@@ -26,7 +26,7 @@ import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.psi.KtElement
 import org.jetbrains.kotlin.psi.KtFile
 
-class FirIdeProvider(
+internal class FirIdeProvider(
     val project: Project,
     val scope: GlobalSearchScope,
     val session: FirSession,
@@ -163,4 +163,4 @@ class FirIdeProvider(
     }
 }
 
-val FirSession.firIdeProvider: FirIdeProvider by FirSession.sessionComponentAccessor()
+internal val FirSession.firIdeProvider: FirIdeProvider by FirSession.sessionComponentAccessor()

idea/idea-frontend-fir/idea-fir-low-level-api/src/org/jetbrains/kotlin/idea/fir/low/level/api/FirIdeResolveStateService.kt

@@ -3,7 +3,7 @@
  * 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.idea.fir
+package org.jetbrains.kotlin.idea.fir.low.level.api
 
 import com.intellij.openapi.components.ServiceManager
 import com.intellij.openapi.project.Project
@@ -12,7 +12,7 @@ import org.jetbrains.kotlin.analyzer.TrackableModuleInfo
 import org.jetbrains.kotlin.fir.java.FirProjectSessionProvider
 import org.jetbrains.kotlin.idea.caches.project.IdeaModuleInfo
 
-interface FirIdeResolveStateService {
+internal interface FirIdeResolveStateService {
     companion object {
         fun getInstance(project: Project): FirIdeResolveStateService =
             ServiceManager.getService(project, FirIdeResolveStateService::class.java)!!
@@ -32,7 +32,7 @@ private class FirModuleData(val state: FirModuleResolveState, val modificationTr
     }
 }
 
-class FirIdeResolveStateServiceImpl(val project: Project) : FirIdeResolveStateService {
+internal class FirIdeResolveStateServiceImpl(val project: Project) : FirIdeResolveStateService {
     private val stateCache = mutableMapOf<IdeaModuleInfo, FirModuleData>()
 
     private fun createResolveState(): FirModuleResolveState {

idea/idea-frontend-fir/idea-fir-low-level-api/src/org/jetbrains/kotlin/idea/fir/low/level/api/FirModuleResolveState.kt

@@ -3,7 +3,7 @@
  * 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.idea.fir
+package org.jetbrains.kotlin.idea.fir.low.level.api
 
 import com.intellij.openapi.project.Project
 import com.intellij.psi.PsiElement
@@ -25,7 +25,7 @@ import org.jetbrains.kotlin.idea.caches.project.getModuleInfo
 import org.jetbrains.kotlin.psi.KtElement
 import org.jetbrains.kotlin.psi.KtFile
 
-interface FirModuleResolveState {
+internal interface FirModuleResolveState {
     val sessionProvider: FirProjectSessionProvider
 
     fun getSession(psi: KtElement): FirSession {
@@ -65,7 +65,7 @@ interface FirModuleResolveState {
     fun setDiagnosticsForFile(file: KtFile, fir: FirFile, diagnostics: Iterable<FirDiagnostic<*>> = emptyList())
 }
 
-class FirModuleResolveStateImpl(override val sessionProvider: FirProjectSessionProvider) : FirModuleResolveState {
+internal class FirModuleResolveStateImpl(override val sessionProvider: FirProjectSessionProvider) : FirModuleResolveState {
     private val cache = mutableMapOf<KtElement, FirElement>()
 
     private val diagnosticCache = mutableMapOf<KtElement, MutableList<Diagnostic>>()
@@ -115,5 +115,5 @@ class FirModuleResolveStateImpl(override val sessionProvider: FirProjectSessionP
     }
 }
 
-fun KtElement.firResolveState(): FirModuleResolveState =
+internal fun KtElement.firResolveState(): FirModuleResolveState =
     FirIdeResolveStateService.getInstance(project).getResolveState(getModuleInfo())

idea/idea-frontend-fir/idea-fir-low-level-api/src/org/jetbrains/kotlin/idea/fir/low/level/api/FirResolution.kt

@@ -3,7 +3,7 @@
  * 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.idea.fir
+package org.jetbrains.kotlin.idea.fir.low.level.api
 
 import com.intellij.openapi.util.registry.Registry
 

idea/idea-frontend-fir/idea-fir-low-level-api/src/org/jetbrains/kotlin/idea/fir/low/level/api/FirResolutionApi.kt

@@ -3,9 +3,8 @@
  * 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.idea.fir
+package org.jetbrains.kotlin.idea.fir.low.level.api
 
-import com.intellij.openapi.progress.ProcessCanceledException
 import com.intellij.openapi.progress.ProgressIndicatorProvider
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.fir.FirElement
@@ -73,7 +72,7 @@ private fun FirFile.findCallableMember(
         ?: error("Cannot find FIR callable declaration ${CallableId(packageFqName, klassFqName, declName)}")
 }
 
-fun KtCallableDeclaration.getOrBuildFir(
+internal fun KtCallableDeclaration.getOrBuildFir(
     state: FirModuleResolveState,
     phase: FirResolvePhase = FirResolvePhase.DECLARATIONS
 ): FirCallableDeclaration<*> {
@@ -97,7 +96,7 @@ fun KtCallableDeclaration.getOrBuildFir(
     return firMemberDeclaration
 }
 
-fun KtClassOrObject.getOrBuildFir(
+internal fun KtClassOrObject.getOrBuildFir(
     state: FirModuleResolveState,
     phase: FirResolvePhase = FirResolvePhase.DECLARATIONS
 ): FirMemberDeclaration {
@@ -131,7 +130,7 @@ private fun KtFile.getOrBuildRawFirFile(state: FirModuleResolveState): Pair<FirI
     return firProvider to firProvider.getOrBuildFile(this)
 }
 
-fun KtFile.getOrBuildFir(
+internal fun KtFile.getOrBuildFir(
     state: FirModuleResolveState,
     phase: FirResolvePhase = FirResolvePhase.DECLARATIONS
 ): FirFile {
@@ -145,7 +144,7 @@ fun KtFile.getOrBuildFir(
     return firFile
 }
 
-fun KtFile.getOrBuildFirWithDiagnostics(state: FirModuleResolveState): FirFile {
+internal fun KtFile.getOrBuildFirWithDiagnostics(state: FirModuleResolveState): FirFile {
     val (_, firFile) = getOrBuildRawFirFile(state)
     val currentResolvePhase = firFile.resolvePhase
     if (currentResolvePhase < FirResolvePhase.BODY_RESOLVE) {
@@ -224,11 +223,6 @@ private class FirDesignatedBodyResolveTransformerForIDE(
     }
 }
 
-inline fun <reified E : FirElement> KtElement.getOrBuildFirSafe(
-    state: FirModuleResolveState,
-    phase: FirResolvePhase = FirResolvePhase.BODY_RESOLVE
-) = getOrBuildFir(state, phase) as? E
-
 
 private fun KtElement.getNonLocalContainingDeclarationWithFqName(): KtDeclaration? {
     var container = parent
@@ -247,7 +241,7 @@ private fun KtElement.getNonLocalContainingDeclarationWithFqName(): KtDeclaratio
     return null
 }
 
-fun KtElement.getOrBuildFir(
+internal fun KtElement.getOrBuildFir(
     state: FirModuleResolveState,
     phase: FirResolvePhase = FirResolvePhase.BODY_RESOLVE
 ): FirElement {

idea/idea-frontend-fir/idea-fir-low-level-api/src/org/jetbrains/kotlin/idea/fir/low/level/api/LowLevelFirApiFacade.kt

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2010-2020 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.idea.fir.low.level.api
+
+import org.jetbrains.kotlin.diagnostics.Diagnostic
+import org.jetbrains.kotlin.fir.FirElement
+import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
+import org.jetbrains.kotlin.psi.KtElement
+
+object LowLevelFirApiFacade {
+    fun getOrBuildFirFor(element: KtElement, phase: FirResolvePhase): FirElement =
+        element.getOrBuildFir(element.firResolveState(), phase)
+
+    fun getDiagnosticsFor(element: KtElement): Collection<Diagnostic> {
+        val file = element.containingKtFile
+        val state = element.firResolveState()
+        file.getOrBuildFirWithDiagnostics(state)
+        return state.getDiagnostics(element)
+    }
+}

idea/idea-frontend-fir/idea-fir-low-level-api/tests/org/jetbrains/kotlin/idea/fir/low/level/api/AbstractFirLazyResolveTest.kt

@@ -3,7 +3,7 @@
  * 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.idea.fir
+package org.jetbrains.kotlin.idea.fir.low.level.api
 
 import com.google.gson.JsonObject
 import com.google.gson.JsonParser

idea/idea-frontend-fir/idea-fir-low-level-api/tests/org/jetbrains/kotlin/idea/fir/low/level/api/AbstractFirMultiModuleResolveTest.kt

@@ -3,11 +3,9 @@
  * 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.idea.fir
+package org.jetbrains.kotlin.idea.fir.low.level.api
 
 import com.intellij.openapi.module.Module
-import com.intellij.openapi.module.ModuleManager
-import com.intellij.openapi.project.Project
 import com.intellij.openapi.vfs.VirtualFile
 import com.intellij.psi.PsiFile
 import com.intellij.psi.PsiManager

idea/idea-frontend-fir/idea-fir-low-level-api/tests/org/jetbrains/kotlin/idea/fir/low/level/api/FirLazyResolveTestGenerated.java

@@ -3,7 +3,7 @@
  * 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.idea.fir;
+package org.jetbrains.kotlin.idea.fir.low.level.api;
 
 import com.intellij.testFramework.TestDataPath;
 import org.jetbrains.kotlin.test.JUnit3RunnerWithInners;
@@ -17,7 +17,7 @@ import java.util.regex.Pattern;
 /** This class is generated by {@link org.jetbrains.kotlin.generators.tests.TestsPackage}. DO NOT MODIFY MANUALLY */
 @SuppressWarnings("all")
 @TestMetadata("idea/testData/fir/lazyResolve")
-@TestDataPath("$PROJECT_ROOT")
+@TestDataPath("/")
 @RunWith(JUnit3RunnerWithInners.class)
 public class FirLazyResolveTestGenerated extends AbstractFirLazyResolveTest {
     private void runTest(String testDataFilePath) throws Exception {

idea/idea-frontend-fir/idea-fir-low-level-api/tests/org/jetbrains/kotlin/idea/fir/low/level/api/FirMultiModuleResolveTestGenerated.java

@@ -3,7 +3,7 @@
  * 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.idea.fir;
+package org.jetbrains.kotlin.idea.fir.low.level.api;
 
 import com.intellij.testFramework.TestDataPath;
 import org.jetbrains.kotlin.test.JUnit3RunnerWithInners;
@@ -17,7 +17,7 @@ import java.util.regex.Pattern;
 /** This class is generated by {@link org.jetbrains.kotlin.generators.tests.TestsPackage}. DO NOT MODIFY MANUALLY */
 @SuppressWarnings("all")
 @TestMetadata("idea/testData/fir/multiModule")
-@TestDataPath("$PROJECT_ROOT")
+@TestDataPath("/")
 @RunWith(JUnit3RunnerWithInners.class)
 public class FirMultiModuleResolveTestGenerated extends AbstractFirMultiModuleResolveTest {
     private void runTest(String testDataFilePath) throws Exception {

idea/idea-frontend-fir/idea-fir-low-level-api/tests/org/jetbrains/kotlin/idea/fir/low/level/api/FirResolveStateTest.kt

@@ -3,9 +3,10 @@
  * 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.idea.fir
+package org.jetbrains.kotlin.idea.fir.low.level.api
 
 import org.jetbrains.kotlin.idea.AbstractResolveElementCacheTest
+import org.jetbrains.kotlin.idea.fir.low.level.api.firResolveState
 
 class FirResolveStateTest : AbstractResolveElementCacheTest() {
     override fun isFirPlugin(): Boolean = true

idea/idea-frontend-fir/idea-fir-low-level-api/tests/org/jetbrains/kotlin/idea/fir/low/level/api/firTestUtils.kt

@@ -3,7 +3,7 @@
  * 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.idea.fir
+package org.jetbrains.kotlin.idea.fir.low.level.api
 
 import com.intellij.openapi.module.ModuleManager
 import com.intellij.openapi.project.Project

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/fir/FirUtils.kt

@@ -5,15 +5,36 @@
 
 package org.jetbrains.kotlin.idea.fir
 
+import com.intellij.psi.util.parentOfType
+import org.jetbrains.kotlin.fir.FirElement
+import org.jetbrains.kotlin.fir.declarations.FirDeclaration
+import org.jetbrains.kotlin.fir.declarations.FirFile
+import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.expressions.FirFunctionCall
 import org.jetbrains.kotlin.fir.expressions.FirQualifiedAccessExpression
 import org.jetbrains.kotlin.fir.references.FirReference
 import org.jetbrains.kotlin.fir.references.FirResolvedNamedReference
 import org.jetbrains.kotlin.fir.symbols.FirBasedSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirNamedFunctionSymbol
-import org.jetbrains.kotlin.idea.references.KtReference
+import org.jetbrains.kotlin.idea.fir.low.level.api.LowLevelFirApiFacade
+import org.jetbrains.kotlin.psi.KtDeclaration
+import org.jetbrains.kotlin.psi.KtElement
 import org.jetbrains.kotlin.util.OperatorNameConventions
 
+fun KtElement.getOrBuildFir(
+    phase: FirResolvePhase = FirResolvePhase.BODY_RESOLVE
+) = LowLevelFirApiFacade.getOrBuildFirFor(this, phase)
+
+
+inline fun <reified E : FirElement> KtElement.getOrBuildFirSafe(
+    phase: FirResolvePhase = FirResolvePhase.BODY_RESOLVE
+) = LowLevelFirApiFacade.getOrBuildFirFor(this, phase) as? E
+
+
+val KtElement.session
+    get() = parentOfType<KtDeclaration>()?.getOrBuildFirSafe<FirDeclaration>()?.session
+        ?: containingKtFile.getOrBuildFirSafe<FirFile>()!!.session
+
 fun FirFunctionCall.isImplicitFunctionCall(): Boolean {
     if (dispatchReceiver !is FirQualifiedAccessExpression) return false
     val resolvedCalleeSymbol = (calleeReference as? FirResolvedNamedReference)?.resolvedSymbol

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/frontend/api/fir/AnalysisSessionFirImpl.kt

@@ -20,18 +20,16 @@ import org.jetbrains.kotlin.fir.symbols.impl.FirConstructorSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirNamedFunctionSymbol
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.idea.fir.*
+import org.jetbrains.kotlin.idea.fir.low.level.api.LowLevelFirApiFacade
 import org.jetbrains.kotlin.idea.frontend.api.*
 import org.jetbrains.kotlin.idea.references.FirReferenceResolveHelper
 import org.jetbrains.kotlin.idea.references.FirReferenceResolveHelper.toTargetPsi
 import org.jetbrains.kotlin.name.ClassId
-import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.types.model.KotlinTypeMarker
 
-class AnalysisSessionFirImpl internal constructor(
+class AnalysisSessionFirImpl : FrontendAnalysisSession() {
-    private val state: FirModuleResolveState
-) : FrontendAnalysisSession() {
 
     override fun getSmartCastedToTypes(expression: KtExpression): Collection<KotlinTypeMarker>? {
         // TODO filter out not used smartcasts
@@ -41,7 +39,7 @@ class AnalysisSessionFirImpl internal constructor(
     @OptIn(ExperimentalStdlibApi::class)
     override fun getImplicitReceiverSmartCasts(expression: KtExpression): Collection<ImplicitReceiverSmartCast> {
         // TODO filter out not used smartcasts
-        val qualifiedExpression = expression.getOrBuildFir(state) as? FirQualifiedAccessExpression ?: return emptyList()
+        val qualifiedExpression = expression.getOrBuildFirSafe<FirQualifiedAccessExpression>() ?: return emptyList()
         if (qualifiedExpression.dispatchReceiver !is FirExpressionWithSmartcast
             && qualifiedExpression.extensionReceiver !is FirExpressionWithSmartcast
         ) return emptyList()
@@ -67,15 +65,13 @@ class AnalysisSessionFirImpl internal constructor(
     override fun isSubclassOf(klass: KtClassOrObject, superClassId: ClassId): Boolean {
         var result = false
         forEachSubClass(klass.toFir() ?: return false) { type ->
-            result = result || type.firClassLike(state.getSession(klass))?.symbol?.classId == superClassId
+            result = result || type.firClassLike(klass.session)?.symbol?.classId == superClassId
         }
         return result
     }
 
-    override fun getDiagnosticsForElement(element: KtElement): Collection<Diagnostic> {
+    override fun getDiagnosticsForElement(element: KtElement): Collection<Diagnostic> =
-        element.containingKtFile.getOrBuildFirWithDiagnostics(state)
+        LowLevelFirApiFacade.getDiagnosticsFor(element)
-        return state.getDiagnostics(element)
-    }
 
     override fun resolveCall(call: KtBinaryExpression): CallInfo? {
         val firCall = call.toFir<FirFunctionCall>() ?: return null
@@ -88,7 +84,7 @@ class AnalysisSessionFirImpl internal constructor(
     }
 
     private fun resolveCall(firCall: FirFunctionCall, callExpression: KtExpression): CallInfo? {
-        val session = callExpression.getSession()
+        val session = callExpression.session
         val resolvedFunctionPsi = firCall.calleeReference.toTargetPsi(session)
         val resolvedCalleeSymbol = (firCall.calleeReference as? FirResolvedNamedReference)?.resolvedSymbol
         return when {
@@ -124,10 +120,8 @@ class AnalysisSessionFirImpl internal constructor(
         else -> null
     }
 
-    private fun KtElement.getSession() = state.getSession(this)
-
     private inline fun <reified F : FirElement> KtElement.toFir(phase: FirResolvePhase = FirResolvePhase.BODY_RESOLVE): F? =
-        getOrBuildFir(state, phase) as? F
+        getOrBuildFir(phase) as? F
 
     private fun forEachSubClass(firClass: FirClass<*>, action: (FirResolvedTypeRef) -> Unit) {
         firClass.superTypeRefs.forEach { superType ->
@@ -137,9 +131,6 @@ class AnalysisSessionFirImpl internal constructor(
     }
 
     companion object {
-        fun forElement(element: KtElement): FrontendAnalysisSession =
-            AnalysisSessionFirImpl(element.firResolveState())
-
         private fun KotlinTypeMarker.asConeType(): ConeKotlinType =
             this as? ConeKotlinType ?: error("$this should be ConeKotlinType")
 
@@ -150,5 +141,4 @@ class AnalysisSessionFirImpl internal constructor(
             )
         }
     }
-
 }

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/highlighter/KotlinFirPsiChecker.kt

@@ -21,7 +21,7 @@ class KotlinFirPsiChecker : AbstractKotlinPsiChecker() {
 
     override fun annotateElement(element: PsiElement, containingFile: KtFile, holder: AnnotationHolder) {
         if (element !is KtElement) return
-        val analysisSession = AnalysisSessionFirImpl.forElement(element)
+        val analysisSession = AnalysisSessionFirImpl()
 
         highlightDiagnostics(element, analysisSession, holder)
 

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/references/FirKtReference.kt

@@ -6,16 +6,10 @@
 package org.jetbrains.kotlin.idea.references
 
 import com.intellij.psi.PsiElement
-import org.jetbrains.kotlin.fir.FirSession
-import org.jetbrains.kotlin.idea.fir.FirModuleResolveState
 import org.jetbrains.kotlin.idea.frontend.api.fir.AnalysisSessionFirImpl
 
 interface FirKtReference : KtReference {
-    fun getResolvedToPsi(
+    fun getResolvedToPsi(analysisSession: AnalysisSessionFirImpl): Collection<PsiElement>
-        analysisSession: AnalysisSessionFirImpl,
-        session: FirSession,
-        state: FirModuleResolveState
-    ): Collection<PsiElement>
 
     override val resolver get() = KtFirReferenceResolver
 }

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/references/FirReferenceResolveHelper.kt

@@ -74,13 +74,11 @@ object FirReferenceResolveHelper {
         }
     }
 
-    internal fun resolveSimpleNameReference(
+    internal fun resolveSimpleNameReference(ref: KtSimpleNameReferenceFirImpl): Collection<PsiElement> {
-        ref: KtSimpleNameReferenceFirImpl,
-        session: FirSession,
-        state: FirModuleResolveState
-    ): Collection<PsiElement> {
         val expression = ref.expression
-        when (val fir = expression.getOrBuildFir(state)) {
+        val fir = expression.getOrBuildFir()
+        val session = expression.session
+        when (fir) {
             is FirResolvable -> {
                 val calleeReference =
                     if (fir is FirFunctionCall
@@ -109,7 +107,7 @@ object FirReferenceResolveHelper {
                         parent = parent.parent as? KtDotQualifiedExpression
                         continue
                     }
-                    val parentFir = selectorExpression.getOrBuildFir(state)
+                    val parentFir = selectorExpression.getOrBuildFir()
                     if (parentFir is FirQualifiedAccess) {
                         return listOfNotNull(classId.toTargetPsi(session, parentFir.calleeReference))
                     }
@@ -177,7 +175,7 @@ object FirReferenceResolveHelper {
                         parent = parent.parent as? KtDotQualifiedExpression
                         continue
                     }
-                    val parentFir = selectorExpression.getOrBuildFir(state)
+                    val parentFir = selectorExpression.getOrBuildFir()
                     if (parentFir is FirResolvedQualifier) {
                         var classId = parentFir.classId
                         while (unresolvedCounter > 0) {

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/references/FirSimpleNameReference.kt

@@ -6,8 +6,6 @@
 package org.jetbrains.kotlin.idea.references
 
 import com.intellij.psi.PsiElement
-import org.jetbrains.kotlin.fir.FirSession
-import org.jetbrains.kotlin.idea.fir.FirModuleResolveState
 import org.jetbrains.kotlin.idea.frontend.api.fir.AnalysisSessionFirImpl
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.psi.KtImportAlias
@@ -16,11 +14,7 @@ import org.jetbrains.kotlin.psi.KtSimpleNameExpression
 internal class KtSimpleNameReferenceFirImpl(
     expression: KtSimpleNameExpression
 ) : KtSimpleNameReference(expression), FirKtReference {
-    override fun getResolvedToPsi(
+    override fun getResolvedToPsi(analysisSession: AnalysisSessionFirImpl) = FirReferenceResolveHelper.resolveSimpleNameReference(this)
-        analysisSession: AnalysisSessionFirImpl,
-        session: FirSession,
-        state: FirModuleResolveState
-    ) = FirReferenceResolveHelper.resolveSimpleNameReference(this, session, state)
 
     override fun doCanBeReferenceTo(candidateTarget: PsiElement): Boolean {
         return true // TODO

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/references/KtDestructuringDeclarationReferenceFirImpl.kt

@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.idea.references
 
 import com.intellij.psi.PsiElement
-import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirProperty
 import org.jetbrains.kotlin.fir.expressions.FirComponentCall
 import org.jetbrains.kotlin.idea.fir.*
@@ -19,12 +18,10 @@ class KtDestructuringDeclarationReferenceFirImpl(
     override fun canRename(): Boolean = false //todo
 
     override fun getResolvedToPsi(
-        analysisSession: AnalysisSessionFirImpl,
+        analysisSession: AnalysisSessionFirImpl
-        session: FirSession,
-        state: FirModuleResolveState
     ): Collection<PsiElement> {
-        val fir = expression.getOrBuildFirSafe<FirProperty>(state) ?: return emptyList()
+        val fir = expression.getOrBuildFirSafe<FirProperty>() ?: return emptyList()
         val componentFunctionSymbol = (fir.initializer as? FirComponentCall)?.getCalleeSymbol() ?: return emptyList()
-        return listOfNotNull(componentFunctionSymbol.fir.findPsi(session))
+        return listOfNotNull(componentFunctionSymbol.fir.findPsi(element.project))
     }
 }

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/references/KtFirReferenceResolver.kt

@@ -9,7 +9,6 @@ import com.intellij.psi.PsiElement
 import com.intellij.psi.PsiElementResolveResult
 import com.intellij.psi.ResolveResult
 import com.intellij.psi.impl.source.resolve.ResolveCache
-import org.jetbrains.kotlin.idea.fir.firResolveState
 import org.jetbrains.kotlin.idea.frontend.api.fir.AnalysisSessionFirImpl
 
 object KtFirReferenceResolver : ResolveCache.PolyVariantResolver<KtReference> {
@@ -18,11 +17,8 @@ object KtFirReferenceResolver : ResolveCache.PolyVariantResolver<KtReference> {
     override fun resolve(ref: KtReference, incompleteCode: Boolean): Array<ResolveResult> {
         check(ref is FirKtReference) { "reference should be FirKtReference, but was ${ref::class}" }
         check(ref is AbstractKtReference<*>) { "reference should be AbstractKtReference, but was ${ref::class}" }
-        val expression = ref.expression
+        val analysisSession = AnalysisSessionFirImpl()
-        val state = expression.firResolveState()
+        val resolveToPsiElements = ref.getResolvedToPsi(analysisSession)
-        val session = state.getSession(expression)
-        val analysisSession = AnalysisSessionFirImpl(state)
-        val resolveToPsiElements = ref.getResolvedToPsi(analysisSession, session, state)
         return resolveToPsiElements.map { KotlinResolveResult(it) }.toTypedArray()
     }
 }

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/references/KtForLoopInReferenceFirImpl.kt

@@ -11,7 +11,6 @@ import org.jetbrains.kotlin.fir.declarations.FirProperty
 import org.jetbrains.kotlin.fir.expressions.FirFunctionCall
 import org.jetbrains.kotlin.fir.expressions.FirQualifiedAccessExpression
 import org.jetbrains.kotlin.fir.expressions.FirWhileLoop
-import org.jetbrains.kotlin.idea.fir.FirModuleResolveState
 import org.jetbrains.kotlin.idea.fir.findPsi
 import org.jetbrains.kotlin.idea.fir.getOrBuildFirSafe
 import org.jetbrains.kotlin.idea.fir.getResolvedSymbolOfNameReference
@@ -20,11 +19,9 @@ import org.jetbrains.kotlin.psi.KtForExpression
 
 open class KtForLoopInReferenceFirImpl(expression: KtForExpression) : KtForLoopInReference(expression), FirKtReference {
     override fun getResolvedToPsi(
-        analysisSession: AnalysisSessionFirImpl,
+        analysisSession: AnalysisSessionFirImpl
-        session: FirSession,
-        state: FirModuleResolveState
     ): Collection<PsiElement> {
-        val firLoop = expression.getOrBuildFirSafe<FirWhileLoop>(state) ?: return emptyList()
+        val firLoop = expression.getOrBuildFirSafe<FirWhileLoop>() ?: return emptyList()
         val condition = firLoop.condition as? FirFunctionCall
         val iterator = run {
             val callee = (condition?.explicitReceiver as? FirQualifiedAccessExpression)?.calleeReference
@@ -32,10 +29,11 @@ open class KtForLoopInReferenceFirImpl(expression: KtForExpression) : KtForLoopI
         }
         val hasNext = condition?.calleeReference?.getResolvedSymbolOfNameReference()
         val next = (firLoop.block.statements.firstOrNull() as? FirProperty?)?.getInitializerFunctionCall()
+        val project = element.project
         return listOfNotNull(
-            iterator?.fir?.findPsi(session),
+            iterator?.fir?.findPsi(project),
-            hasNext?.fir?.findPsi(session),
+            hasNext?.fir?.findPsi(project),
-            next?.fir?.findPsi(session),
+            next?.fir?.findPsi(project),
         )
     }
 

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/references/KtInvokeFunctionReferenceFirImpl.kt

@@ -6,8 +6,6 @@
 package org.jetbrains.kotlin.idea.references
 
 import com.intellij.psi.PsiElement
-import org.jetbrains.kotlin.fir.FirSession
-import org.jetbrains.kotlin.idea.fir.FirModuleResolveState
 import org.jetbrains.kotlin.idea.frontend.api.VariableAsFunctionLikeCallInfo
 import org.jetbrains.kotlin.idea.frontend.api.fir.AnalysisSessionFirImpl
 import org.jetbrains.kotlin.psi.KtCallExpression
@@ -18,11 +16,7 @@ class KtInvokeFunctionReferenceFirImpl(expression: KtCallExpression) : KtInvokeF
         TODO("Not yet implemented")
     }
 
-    override fun getResolvedToPsi(
+    override fun getResolvedToPsi(analysisSession: AnalysisSessionFirImpl): Collection<PsiElement> {
-        analysisSession: AnalysisSessionFirImpl,
-        session: FirSession,
-        state: FirModuleResolveState
-    ): Collection<PsiElement> {
         val call = analysisSession.resolveCall(expression) ?: return emptyList()
         if (call is VariableAsFunctionLikeCallInfo) {
             return listOf(call.invokeFunction)

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/references/KtPropertyDelegationMethodsReferenceFirImpl.kt

@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.idea.references
 
 import com.intellij.psi.PsiElement
-import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirProperty
 import org.jetbrains.kotlin.fir.declarations.FirPropertyAccessor
 import org.jetbrains.kotlin.fir.expressions.FirFunctionCall
@@ -21,17 +20,16 @@ class KtPropertyDelegationMethodsReferenceFirImpl(
     element: KtPropertyDelegate
 ) : KtPropertyDelegationMethodsReference(element), FirKtReference {
     override fun getResolvedToPsi(
-        analysisSession: AnalysisSessionFirImpl,
+        analysisSession: AnalysisSessionFirImpl
-        session: FirSession,
-        state: FirModuleResolveState
     ): Collection<PsiElement> {
-        val property = (expression.parent as? KtElement)?.getOrBuildFirSafe<FirProperty>(state) ?: return emptyList()
+        val property = (expression.parent as? KtElement)?.getOrBuildFirSafe<FirProperty>() ?: return emptyList()
         if (property.delegate == null) return emptyList()
         val getValueSymbol = (property.getter?.singleStatementOfType<FirReturnExpression>()?.result as? FirFunctionCall)?.getCalleeSymbol()
         val setValueSymbol = property.setter?.singleStatementOfType<FirFunctionCall>()?.getCalleeSymbol()
+        val project = element.project
         return listOfNotNull(
-            getValueSymbol?.fir?.findPsi(session),
+            getValueSymbol?.fir?.findPsi(project),
-            setValueSymbol?.fir?.findPsi(session)
+            setValueSymbol?.fir?.findPsi(project)
         )
     }
 

idea/idea-frontend-fir/tests/org/jetbrains/kotlin/idea/fir/AbstractKtDeclarationAndFirDeclarationEqualityChecker.kt

@@ -7,8 +7,6 @@ package org.jetbrains.kotlin.idea.fir
 
 import com.intellij.openapi.util.io.FileUtil
 import com.intellij.rt.execution.junit.FileComparisonFailure
-import junit.framework.Assert
-import junit.framework.ComparisonFailure
 import org.jetbrains.kotlin.fir.declarations.FirFunction
 import org.jetbrains.kotlin.idea.test.KotlinLightCodeInsightFixtureTestCase
 import org.jetbrains.kotlin.psi.KtFile
@@ -21,9 +19,8 @@ abstract class AbstractKtDeclarationAndFirDeclarationEqualityChecker : KotlinLig
         val file = File(path)
         val ktFile = myFixture.configureByText(file.name, FileUtil.loadFile(file)) as KtFile
 
-        val resolveState = ktFile.firResolveState()
         ktFile.forEachDescendantOfType<KtFunction> { ktFunction ->
-            val firFunction = ktFunction.getOrBuildFir(resolveState) as FirFunction<*>
+            val firFunction = ktFunction.getOrBuildFir() as FirFunction<*>
             if (!KtDeclarationAndFirDeclarationEqualityChecker.representsTheSameDeclaration(ktFunction, firFunction)) {
                 throw FileComparisonFailure(
                     /* message= */          null,

idea/resources-fir/META-INF/plugin.xml

@@ -92,8 +92,8 @@ The Kotlin FIR plugin provides language support in IntelliJ IDEA and Android Stu
     <applicationService serviceImplementation="org.jetbrains.kotlin.idea.PluginStartupService"/>
     <highlightRangeExtension implementation="org.jetbrains.kotlin.idea.highlighter.KotlinFirPsiChecker"/>
     <annotator language="kotlin" implementationClass="org.jetbrains.kotlin.idea.highlighter.KotlinFirPsiChecker"/>
-    <projectService serviceInterface="org.jetbrains.kotlin.idea.fir.FirIdeResolveStateService"
+    <projectService serviceInterface="org.jetbrains.kotlin.idea.fir.low.level.api.FirIdeResolveStateService"
-                    serviceImplementation="org.jetbrains.kotlin.idea.fir.FirIdeResolveStateServiceImpl"/>
+                    serviceImplementation="org.jetbrains.kotlin.idea.fir.low.level.api.FirIdeResolveStateServiceImpl"/>
     <projectService serviceImplementation="org.jetbrains.kotlin.resolve.jvm.KotlinJavaPsiFacade"/>
   </extensions>
 

prepare/idea-plugin/build.gradle.kts

@@ -95,7 +95,8 @@ val projectsToShadow by extra(listOf(
         ":idea:idea-jps-common",
         ":idea:idea-frontend-independent",
         ":idea:idea-frontend-fir",
-        ":idea:idea-frontend-api",
+        ":idea:idea-frontend-fir",
+        ":idea:idea-frontend-fir:idea-fir-low-level-api",
         *if (Ide.IJ())
             arrayOf(
                 ":idea:idea-maven",

settings.gradle

@@ -313,6 +313,8 @@ include ":kotlin-build-common",
         ":kotlin-serialization-unshaded",
         ":kotlin-serialization:plugin-marker"
 
+include ":idea:idea-frontend-fir:idea-fir-low-level-api"
+
 include ":prepare:ide-plugin-dependencies:android-extensions-compiler-plugin-for-ide",
         ":prepare:ide-plugin-dependencies:allopen-compiler-plugin-for-ide",
         ":prepare:ide-plugin-dependencies:allopen-compiler-plugin-tests-for-ide",