[FIR] Extract java class mapping to platform specific component

compiler/fir/java/src/org/jetbrains/kotlin/fir/java/JavaSessionUtils.kt

@@ -8,9 +8,11 @@ package org.jetbrains.kotlin.fir.java
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.registerJvmEffectiveVisibilityResolver
 import org.jetbrains.kotlin.fir.resolve.calls.jvm.registerJvmCallConflictResolverFactory
+import org.jetbrains.kotlin.fir.resolve.registerJavaClassMapper
 
 fun FirSession.registerJavaSpecificComponents() {
     registerJavaVisibilityChecker()
     registerJvmCallConflictResolverFactory()
     registerJvmEffectiveVisibilityResolver()
+    registerJavaClassMapper()
 }

compiler/fir/jvm/src/org/jetbrains/kotlin/fir/resolve/FirJavaClassMapper.kt

@@ -0,0 +1,22 @@
+/*
+ * 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.fir.resolve
+
+import org.jetbrains.kotlin.builtins.jvm.JavaToKotlinClassMap
+import org.jetbrains.kotlin.fir.FirSession
+import org.jetbrains.kotlin.fir.declarations.FirClassLikeDeclaration
+import org.jetbrains.kotlin.fir.declarations.FirRegularClass
+
+class FirJavaClassMapper(private val session: FirSession) : FirPlatformClassMapper() {
+    override fun getCorrespondingPlatformClass(declaration: FirClassLikeDeclaration<*>): FirRegularClass? {
+        val javaClassId = JavaToKotlinClassMap.mapKotlinToJava(declaration.symbol.classId.asSingleFqName().toUnsafe())
+        return javaClassId?.let { session.firSymbolProvider.getClassLikeSymbolByFqName(it)?.fir } as? FirRegularClass
+    }
+}
+
+fun FirSession.registerJavaClassMapper() {
+    register(FirPlatformClassMapper::class, FirJavaClassMapper(this))
+}

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/FirPlatformClassMapper.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.fir.resolve
+
+import org.jetbrains.kotlin.fir.FirSession
+import org.jetbrains.kotlin.fir.FirSessionComponent
+import org.jetbrains.kotlin.fir.declarations.FirClassLikeDeclaration
+import org.jetbrains.kotlin.fir.declarations.FirRegularClass
+
+abstract class FirPlatformClassMapper : FirSessionComponent {
+    object Default : FirPlatformClassMapper() {
+        override fun getCorrespondingPlatformClass(declaration: FirClassLikeDeclaration<*>): FirRegularClass? {
+            return null
+        }
+    }
+
+    abstract fun getCorrespondingPlatformClass(declaration: FirClassLikeDeclaration<*>): FirRegularClass?
+}
+
+val FirSession.platformClassMapper: FirPlatformClassMapper by FirSession.sessionComponentAccessor()

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/SupertypeUtils.kt

@@ -5,16 +5,15 @@
 
 package org.jetbrains.kotlin.fir.resolve
 
-import org.jetbrains.kotlin.builtins.jvm.JavaToKotlinClassMap
 import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.*
 import org.jetbrains.kotlin.fir.resolve.transformers.createSubstitutionForSupertype
-import org.jetbrains.kotlin.fir.typeContext
-import org.jetbrains.kotlin.fir.scopes.FirTypeScope
 import org.jetbrains.kotlin.fir.scopes.FirScope
+import org.jetbrains.kotlin.fir.scopes.FirTypeScope
 import org.jetbrains.kotlin.fir.scopes.impl.FirClassSubstitutionScope
 import org.jetbrains.kotlin.fir.symbols.impl.*
+import org.jetbrains.kotlin.fir.typeContext
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.name.ClassId
 
@@ -94,16 +93,15 @@ fun ConeClassLikeType.wrapSubstitutionScopeIfNeed(
     return builder.getOrBuild(declaration.symbol, SubstitutionScopeKey(this)) {
         val typeParameters = (declaration as? FirTypeParameterRefsOwner)?.typeParameters.orEmpty()
         val originalSubstitution = createSubstitution(typeParameters, typeArguments, session)
-        val javaClassId = JavaToKotlinClassMap.mapKotlinToJava(declaration.symbol.classId.asSingleFqName().toUnsafe())
+        val platformClass = session.platformClassMapper.getCorrespondingPlatformClass(declaration)
-        val javaClass = javaClassId?.let { session.firSymbolProvider.getClassLikeSymbolByFqName(it)?.fir } as? FirRegularClass
+        if (platformClass != null) {
-        if (javaClass != null) {
             // This kind of substitution is necessary when method which is mapped from Java (e.g. Java Map.forEach)
             // is called on an external type, like MyMap<String, String>,
             // to determine parameter types properly (e.g. String, String instead of K, V)
-            val javaTypeParameters = javaClass.typeParameters
+            val platformTypeParameters = platformClass.typeParameters
-            val javaSubstitution = createSubstitution(javaTypeParameters, typeArguments, session)
+            val platformSubstitution = createSubstitution(platformTypeParameters, typeArguments, session)
             FirClassSubstitutionScope(
-                session, useSiteMemberScope, builder, originalSubstitution + javaSubstitution,
+                session, useSiteMemberScope, builder, originalSubstitution + platformSubstitution,
                 skipPrivateMembers = true, derivedClassId = derivedClassId
             )
         } else {