Add getExtensionOrNull utility for protobuf messages

core/descriptors.jvm/src/org/jetbrains/kotlin/load/kotlin/AbstractBinaryClassAnnotationAndConstantLoader.kt

@@ -311,9 +311,7 @@ abstract class AbstractBinaryClassAnnotationAndConstantLoader<A : Any, C : Any,
             field: Boolean = false,
             synthetic: Boolean = false
     ): MemberSignature? {
-        val signature =
-                if (proto.hasExtension(propertySignature)) proto.getExtension(propertySignature)
-                else return null
+        val signature = proto.getExtensionOrNull(propertySignature) ?: return null
 
         if (field) {
             val (name, desc) = JvmProtoBufUtil.getJvmFieldSignature(proto, nameResolver, typeTable) ?: return null
@@ -339,8 +337,8 @@ abstract class AbstractBinaryClassAnnotationAndConstantLoader<A : Any, C : Any,
             proto is ProtoBuf.Function -> {
                 MemberSignature.fromMethodNameAndDesc(JvmProtoBufUtil.getJvmMethodSignature(proto, nameResolver, typeTable) ?: return null)
             }
-            proto is ProtoBuf.Property && proto.hasExtension(propertySignature) -> {
-                val signature = proto.getExtension(propertySignature)
+            proto is ProtoBuf.Property -> {
+                val signature = proto.getExtensionOrNull(propertySignature) ?: return null
                 when (kind) {
                     AnnotatedCallableKind.PROPERTY_GETTER -> MemberSignature.fromMethod(nameResolver, signature.getter)
                     AnnotatedCallableKind.PROPERTY_SETTER -> MemberSignature.fromMethod(nameResolver, signature.setter)

core/descriptors.jvm/src/org/jetbrains/kotlin/serialization/jvm/JvmProtoBufUtil.kt

@@ -63,8 +63,7 @@ object JvmProtoBufUtil {
             nameResolver: NameResolver,
             typeTable: TypeTable
     ): String? {
-        val signature =
-                if (proto.hasExtension(JvmProtoBuf.methodSignature)) proto.getExtension(JvmProtoBuf.methodSignature) else null
+        val signature = proto.getExtensionOrNull(JvmProtoBuf.methodSignature)
         val name = if (signature != null && signature.hasName()) signature.name else proto.name
         val desc = if (signature != null && signature.hasDesc()) {
             nameResolver.getString(signature.desc)
@@ -85,8 +84,7 @@ object JvmProtoBufUtil {
             nameResolver: NameResolver,
             typeTable: TypeTable
     ): String? {
-        val signature =
-                if (proto.hasExtension(JvmProtoBuf.constructorSignature)) proto.getExtension(JvmProtoBuf.constructorSignature) else null
+        val signature = proto.getExtensionOrNull(JvmProtoBuf.constructorSignature)
         val desc = if (signature != null && signature.hasDesc()) {
             nameResolver.getString(signature.desc)
         }
@@ -103,8 +101,7 @@ object JvmProtoBufUtil {
             nameResolver: NameResolver,
             typeTable: TypeTable
     ): PropertySignature? {
-        val signature =
-                if (proto.hasExtension(JvmProtoBuf.propertySignature)) proto.getExtension(JvmProtoBuf.propertySignature) else return null
+        val signature = proto.getExtensionOrNull(JvmProtoBuf.propertySignature) ?: return null
         val field =
                 if (signature.hasField()) signature.field else null
 

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

@@ -90,8 +90,7 @@ class AnnotationAndConstantLoaderImpl(
             proto: ProtoBuf.Property,
             expectedType: KotlinType
     ): ConstantValue<*>? {
-        if (!proto.hasExtension(protocol.compileTimeValue)) return null
-        val value = proto.getExtension(protocol.compileTimeValue)
+        val value = proto.getExtensionOrNull(protocol.compileTimeValue) ?: return null
         return deserializer.resolveValue(expectedType, value, container.nameResolver)
     }
 }

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

@@ -0,0 +1,12 @@
+/*
+ * Copyright 2000-2018 JetBrains s.r.o. 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.protobuf.GeneratedMessageLite
+
+fun <M : GeneratedMessageLite.ExtendableMessage<M>, T> GeneratedMessageLite.ExtendableMessage<M>.getExtensionOrNull(
+    extension: GeneratedMessageLite.GeneratedExtension<M, T>
+): T? = if (hasExtension(extension)) getExtension(extension) else null

core/reflection.jvm/src/kotlin/reflect/jvm/internal/RuntimeTypeMapper.kt

@@ -40,6 +40,7 @@ import org.jetbrains.kotlin.serialization.deserialization.TypeTable
 import org.jetbrains.kotlin.serialization.deserialization.descriptors.DeserializedCallableMemberDescriptor
 import org.jetbrains.kotlin.serialization.deserialization.descriptors.DeserializedClassDescriptor
 import org.jetbrains.kotlin.serialization.deserialization.descriptors.DeserializedPropertyDescriptor
+import org.jetbrains.kotlin.serialization.deserialization.getExtensionOrNull
 import org.jetbrains.kotlin.serialization.jvm.JvmProtoBuf
 import org.jetbrains.kotlin.serialization.jvm.JvmProtoBufUtil
 import java.lang.reflect.Constructor
@@ -120,10 +121,8 @@ internal sealed class JvmPropertySignature {
             val containingDeclaration = descriptor.containingDeclaration
             if (descriptor.visibility == Visibilities.INTERNAL && containingDeclaration is DeserializedClassDescriptor) {
                 val classProto = containingDeclaration.classProto
-                val moduleName =
-                        if (classProto.hasExtension(JvmProtoBuf.classModuleName))
-                            nameResolver.getString(classProto.getExtension(JvmProtoBuf.classModuleName))
-                        else JvmAbi.DEFAULT_MODULE_NAME
+                val moduleName = classProto.getExtensionOrNull(JvmProtoBuf.classModuleName)?.let(nameResolver::getString)
+                        ?: JvmAbi.DEFAULT_MODULE_NAME
                 return "$" + NameUtils.sanitizeAsJavaIdentifier(moduleName)
             }
             if (descriptor.visibility == Visibilities.PRIVATE && containingDeclaration is PackageFragmentDescriptor) {
@@ -210,14 +209,12 @@ internal object RuntimeTypeMapper {
         return when (property) {
             is DeserializedPropertyDescriptor -> {
                 val proto = property.proto
-                if (!proto.hasExtension(JvmProtoBuf.propertySignature)) {
-                    // If this property has no JVM signature, it must be from built-ins
-                    throw KotlinReflectionInternalError("Reflection on built-in Kotlin types is not yet fully supported. " +
-                                                        "No metadata found for $property")
-                }
-                JvmPropertySignature.KotlinProperty(
-                        property, proto, proto.getExtension(JvmProtoBuf.propertySignature), property.nameResolver, property.typeTable
-                )
+                val signature = proto.getExtensionOrNull(JvmProtoBuf.propertySignature)
+                        ?: // If this property has no JVM signature, it must be from built-ins
+                        throw KotlinReflectionInternalError(
+                            "Reflection on built-in Kotlin types is not yet fully supported. No metadata found for $property"
+                        )
+                JvmPropertySignature.KotlinProperty(property, proto, signature, property.nameResolver, property.typeTable)
             }
             is JavaPropertyDescriptor -> {
                 val element = (property.source as? JavaSourceElement)?.javaElement

core/reflection.jvm/src/kotlin/reflect/jvm/internal/util.kt

@@ -28,10 +28,7 @@ import org.jetbrains.kotlin.protobuf.MessageLite
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.descriptorUtil.classId
 import org.jetbrains.kotlin.serialization.ProtoBuf
-import org.jetbrains.kotlin.serialization.deserialization.DeserializationContext
-import org.jetbrains.kotlin.serialization.deserialization.MemberDeserializer
-import org.jetbrains.kotlin.serialization.deserialization.NameResolver
-import org.jetbrains.kotlin.serialization.deserialization.TypeTable
+import org.jetbrains.kotlin.serialization.deserialization.*
 import org.jetbrains.kotlin.serialization.deserialization.descriptors.VersionRequirementTable
 import org.jetbrains.kotlin.serialization.jvm.JvmProtoBuf
 import org.jetbrains.kotlin.serialization.jvm.JvmProtoBufUtil
@@ -139,9 +136,7 @@ internal val ReflectKotlinClass.packageModuleName: String?
                 val (nameResolver, proto) = JvmProtoBufUtil.readPackageDataFrom(header.data!!, header.strings!!)
                 // If no packageModuleName extension is written, the name is assumed to be JvmAbi.DEFAULT_MODULE_NAME
                 // (see JvmSerializerExtension.serializePackage)
-                if (proto.hasExtension(JvmProtoBuf.packageModuleName))
-                    nameResolver.getString(proto.getExtension(JvmProtoBuf.packageModuleName))
-                else JvmAbi.DEFAULT_MODULE_NAME
+                proto.getExtensionOrNull(JvmProtoBuf.packageModuleName)?.let(nameResolver::getString) ?: JvmAbi.DEFAULT_MODULE_NAME
             }
             KotlinClassHeader.Kind.MULTIFILE_CLASS -> {
                 val partName = header.multifilePartNames.firstOrNull() ?: return null