[K2] Pass FirFile to metadata serialization

This is needed to extract correct const value from `ConstValueProvider`.

#KT-57812

compiler/fir/fir-serialization/src/org/jetbrains/kotlin/fir/serialization/FirElementSerializer.kt

@@ -78,7 +78,7 @@ class FirElementSerializer private constructor(
 
     fun packagePartProto(
         packageFqName: FqName,
-        files: List<FirFile>,
+        file: FirFile,
         actualizedExpectDeclarations: Set<FirDeclaration>?
     ): ProtoBuf.Package.Builder {
         val builder = ProtoBuf.Package.newBuilder()
@@ -88,7 +88,7 @@ class FirElementSerializer private constructor(
                 if (!declaration.shouldBeSerialized(actualizedExpectDeclarations)) return
                 when (declaration) {
                     is FirProperty -> propertyProto(declaration)?.let { builder.addProperty(it) }
-                    is FirSimpleFunction -> functionProto(declaration)?.let { builder.addFunction(it) }
+                    is FirSimpleFunction -> privateFunctionProto(declaration)?.let { builder.addFunction(it) }
                     is FirTypeAlias -> typeAliasProto(declaration)?.let { builder.addTypeAlias(it) }
                     else -> onUnsupportedDeclaration(declaration)
                 }
@@ -97,18 +97,16 @@ class FirElementSerializer private constructor(
             }
         }
 
-        for (file in files) {
-            extension.processFile(file) {
-                for (declaration in file.declarations) {
-                    addDeclaration(declaration) {}
-                }
+        processFile(file) {
+            for (declaration in file.declarations) {
+                addDeclaration(declaration) {}
             }
-        }
+            extension.serializePackage(packageFqName, builder)
 
-        extension.serializePackage(packageFqName, builder)
-        for (declaration in providedDeclarationsService.getProvidedTopLevelDeclarations(packageFqName, scopeSession)) {
-            addDeclaration(declaration) {
-                error("Unsupported top-level declaration type: ${it.render()}")
+            for (declaration in providedDeclarationsService.getProvidedTopLevelDeclarations(packageFqName, scopeSession)) {
+                addDeclaration(declaration) {
+                    error("Unsupported top-level declaration type: ${it.render()}")
+                }
             }
         }
 
@@ -118,7 +116,20 @@ class FirElementSerializer private constructor(
         return builder
     }
 
-    fun classProto(klass: FirClass): ProtoBuf.Class.Builder = whileAnalysing(session, klass) {
+    private inline fun <T> processFile(firFile: FirFile, crossinline action: () -> T): T {
+        return extension.processFile(firFile) {
+            action()
+        }
+    }
+
+    // Note: we could try to extract FirFile from `session.firProvider.getFirClassifierContainerFile` but it doesn't work for anonymous objects
+    fun classProto(klass: FirClass, firFile: FirFile): ProtoBuf.Class.Builder {
+        return processFile(firFile) {
+            privateClassProto(klass)
+        }
+    }
+
+    private fun privateClassProto(klass: FirClass): ProtoBuf.Class.Builder = whileAnalysing(session, klass) {
         val builder = ProtoBuf.Class.newBuilder()
 
         val regularClass = klass as? FirRegularClass
@@ -198,7 +209,7 @@ class FirElementSerializer private constructor(
             if (declaration !is FirEnumEntry && declaration.isStatic) continue // ??? Miss values() & valueOf()
             when (declaration) {
                 is FirProperty -> propertyProto(declaration)?.let { builder.addProperty(it) }
-                is FirSimpleFunction -> functionProto(declaration)?.let { builder.addFunction(it) }
+                is FirSimpleFunction -> privateFunctionProto(declaration)?.let { builder.addFunction(it) }
                 is FirEnumEntry -> enumEntryProto(declaration).let { builder.addEnumEntry(it) }
                 else -> {}
             }
@@ -489,7 +500,13 @@ class FirElementSerializer private constructor(
         return builder
     }
 
-    fun functionProto(function: FirFunction): ProtoBuf.Function.Builder? = whileAnalysing(session, function) {
+    fun functionProto(function: FirFunction, firFile: FirFile): ProtoBuf.Function.Builder? {
+        return processFile(firFile) {
+            privateFunctionProto(function)
+        }
+    }
+
+    fun privateFunctionProto(function: FirFunction): ProtoBuf.Function.Builder? = whileAnalysing(session, function) {
         val builder = ProtoBuf.Function.newBuilder()
         val simpleFunction = function as? FirSimpleFunction
 

compiler/fir/fir-serialization/src/org/jetbrains/kotlin/fir/serialization/FirSerializerExtension.kt

@@ -8,8 +8,8 @@ package org.jetbrains.kotlin.fir.serialization
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.*
 import org.jetbrains.kotlin.fir.expressions.FirAnnotation
-import org.jetbrains.kotlin.fir.serialization.constant.ConstValueProviderInternals
 import org.jetbrains.kotlin.fir.serialization.constant.ConstValueProvider
+import org.jetbrains.kotlin.fir.serialization.constant.ConstValueProviderInternals
 import org.jetbrains.kotlin.fir.types.ConeErrorType
 import org.jetbrains.kotlin.fir.types.ConeFlexibleType
 import org.jetbrains.kotlin.metadata.ProtoBuf
@@ -29,7 +29,7 @@ abstract class FirSerializerExtension {
     protected abstract val constValueProvider: ConstValueProvider?
 
     @OptIn(ConstValueProviderInternals::class)
-    internal inline fun <T> processFile(firFile: FirFile, action: () -> T): T {
+    internal inline fun <T> processFile(firFile: FirFile, crossinline action: () -> T): T {
         val previousFile = constValueProvider?.processingFirFile
         constValueProvider?.processingFirFile = firFile
         return try {

compiler/fir/fir-serialization/src/org/jetbrains/kotlin/fir/serialization/firKlibSerialization.kt

@@ -35,7 +35,7 @@ fun serializeSingleFirFile(
     // TODO: split package fragment (see klib serializer)
     // TODO: handle incremental/monolothic (see klib serializer) - maybe externally
 
-    val packageProto = packageSerializer.packagePartProto(file.packageFqName, listOf(file), actualizedExpectDeclarations).build()
+    val packageProto = packageSerializer.packagePartProto(file.packageFqName, file, actualizedExpectDeclarations).build()
 
     val classesProto = mutableListOf<Pair<ProtoBuf.Class, Int>>()
 
@@ -51,14 +51,12 @@ fun serializeSingleFirFile(
             )
             val index = classSerializer.stringTable.getFqNameIndex(klass)
 
-            classesProto += classSerializer.classProto(klass).build() to index
+            classesProto += classSerializer.classProto(klass, file).build() to index
             classSerializer.computeNestedClassifiersForClass(symbol).filterIsInstance<FirClassSymbol<*>>().makeClassesProtoWithNested()
         }
     }
 
-    serializerExtension.processFile(file) {
-        file.declarations.mapNotNull { it.symbol as? FirClassSymbol<*> }.makeClassesProtoWithNested()
-    }
+    file.declarations.mapNotNull { it.symbol as? FirClassSymbol<*> }.makeClassesProtoWithNested()
 
     val hasTopLevelDeclarations = file.declarations.any {
         it is FirMemberDeclaration && it.shouldBeSerialized(actualizedExpectDeclarations) &&