[FIR] Add MetadataSymbolProvider

Extract common code from K1 to MetadataUtil

core/compiler.common/src/org/jetbrains/kotlin/serialization/deserialization/KotlinMetadataFinder.kt

@@ -27,6 +27,8 @@ interface KotlinMetadataFinder {
      */
     fun findMetadata(classId: ClassId): InputStream?
 
+    fun findMetadataTopLevelClassesInPackage(packageFqName: FqName): Set<String>?
+
     /**
      * @return `true` iff this finder is able to locate the package with the given [fqName], containing .kotlin_metadata files.
      * Note that returning `true` makes [MetadataPackageFragmentProvider] construct the package fragment for the package,

core/descriptors.runtime/src/org/jetbrains/kotlin/descriptors/runtime/components/ReflectKotlinClassFinder.kt

@@ -45,6 +45,9 @@ class ReflectKotlinClassFinder(private val classLoader: ClassLoader) : KotlinCla
     // TODO
     override fun findMetadata(classId: ClassId): InputStream? = null
 
+    // TODO
+    override fun findMetadataTopLevelClassesInPackage(packageFqName: FqName): Set<String>? = null
+
     // TODO
     override fun hasMetadataPackage(fqName: FqName): Boolean = false
 

core/deserialization.common/src/org/jetbrains/kotlin/serialization/deserialization/MetadataUtil.kt

@@ -0,0 +1,44 @@
+/*
+ * Copyright 2010-2023 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.serialization.deserialization
+
+import org.jetbrains.kotlin.descriptors.SourceElement
+import org.jetbrains.kotlin.metadata.ProtoBuf
+import org.jetbrains.kotlin.metadata.builtins.BuiltInsBinaryVersion
+import org.jetbrains.kotlin.metadata.deserialization.NameResolverImpl
+import org.jetbrains.kotlin.name.ClassId
+import org.jetbrains.kotlin.serialization.deserialization.builtins.BuiltInSerializerProtocol
+import java.io.InputStream
+
+class MetadataClassDataFinder(val finder: KotlinMetadataFinder) : ClassDataFinder {
+    override fun findClassData(classId: ClassId): ClassData? {
+        val topLevelClassId = generateSequence(classId, ClassId::getOuterClassId).last()
+        val stream = finder.findMetadata(topLevelClassId) ?: return null
+        val (message, nameResolver, version) = readProto(stream)
+        return message.class_List.firstOrNull { classProto ->
+            nameResolver.getClassId(classProto.fqName) == classId
+        }?.let { classProto ->
+            ClassData(nameResolver, classProto, version, SourceElement.NO_SOURCE)
+        }
+    }
+}
+
+fun readProto(stream: InputStream): Triple<ProtoBuf.PackageFragment, NameResolverImpl, BuiltInsBinaryVersion> {
+    val version = BuiltInsBinaryVersion.readFrom(stream)
+
+    if (!version.isCompatibleWithCurrentCompilerVersion()) {
+        // TODO: report a proper diagnostic
+        throw UnsupportedOperationException(
+            "Kotlin metadata definition format version is not supported: " +
+                    "expected ${BuiltInsBinaryVersion.INSTANCE}, actual $version. " +
+                    "Please update Kotlin"
+        )
+    }
+
+    val message = ProtoBuf.PackageFragment.parseFrom(stream, BuiltInSerializerProtocol.extensionRegistry)
+    val nameResolver = NameResolverImpl(message.strings, message.qualifiedNames)
+    return Triple(message, nameResolver, version)
+}

core/deserialization/src/org/jetbrains/kotlin/serialization/deserialization/MetadataPackageFragmentProvider.kt

@@ -18,7 +18,6 @@ package org.jetbrains.kotlin.serialization.deserialization
 
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
 import org.jetbrains.kotlin.descriptors.NotFoundClasses
-import org.jetbrains.kotlin.descriptors.SourceElement
 import org.jetbrains.kotlin.descriptors.deserialization.AdditionalClassPartsProvider
 import org.jetbrains.kotlin.descriptors.deserialization.PlatformDependentDeclarationFilter
 import org.jetbrains.kotlin.incremental.components.LookupTracker
@@ -36,7 +35,6 @@ import org.jetbrains.kotlin.serialization.deserialization.descriptors.Deserializ
 import org.jetbrains.kotlin.storage.StorageManager
 import org.jetbrains.kotlin.types.checker.NewKotlinTypeChecker
 import org.jetbrains.kotlin.types.extensions.TypeAttributeTranslators
-import java.io.InputStream
 
 class MetadataPackageFragmentProvider(
     storageManager: StorageManager,
@@ -85,16 +83,7 @@ class MetadataPackageFragment(
     private val metadataPartProvider: MetadataPartProvider,
     private val finder: KotlinMetadataFinder
 ) : DeserializedPackageFragment(fqName, storageManager, module) {
-    override val classDataFinder = ClassDataFinder { classId ->
-        val topLevelClassId = generateSequence(classId, ClassId::getOuterClassId).last()
-        val stream = finder.findMetadata(topLevelClassId) ?: return@ClassDataFinder null
-        val (message, nameResolver, version) = readProto(stream)
-        message.class_List.firstOrNull { classProto ->
-            nameResolver.getClassId(classProto.fqName) == classId
-        }?.let { classProto ->
-            ClassData(nameResolver, classProto, version, SourceElement.NO_SOURCE)
-        }
-    }
+    override val classDataFinder = MetadataClassDataFinder(finder)
 
     private lateinit var components: DeserializationComponents
 
@@ -152,23 +141,6 @@ class MetadataPackageFragment(
         return true
     }
 
-    private fun readProto(stream: InputStream): Triple<ProtoBuf.PackageFragment, NameResolverImpl, BuiltInsBinaryVersion> {
-        val version = BuiltInsBinaryVersion.readFrom(stream)
-
-        if (!version.isCompatibleWithCurrentCompilerVersion()) {
-            // TODO: report a proper diagnostic
-            throw UnsupportedOperationException(
-                "Kotlin metadata definition format version is not supported: " +
-                        "expected ${BuiltInsBinaryVersion.INSTANCE}, actual $version. " +
-                        "Please update Kotlin"
-            )
-        }
-
-        val message = ProtoBuf.PackageFragment.parseFrom(stream, BuiltInSerializerProtocol.extensionRegistry)
-        val nameResolver = NameResolverImpl(message.strings, message.qualifiedNames)
-        return Triple(message, nameResolver, version)
-    }
-
     companion object {
         const val METADATA_FILE_EXTENSION = "kotlin_metadata"
         const val DOT_METADATA_FILE_EXTENSION = ".$METADATA_FILE_EXTENSION"