K2 support (#1525)

Author: rorbech

CHANGELOG.md

@@ -4,7 +4,7 @@
 * None.
 
 ### Enhancements
-* None.
+* Support for experimental K2-compilation with `kotlin.experimental.tryK2=true`. (Issue [#1483](https://github.com/realm/realm-kotlin/issues/1483))
 
 ### Fixed
 * None.
@@ -13,7 +13,7 @@
 * File format: Generates Realms with file format v23.
 * Realm Studio 13.0.0 or above is required to open Realms created by this version.
 * This release is compatible with the following Kotlin releases:
-  * Kotlin 1.8.0 and above. The K2 compiler is not supported yet.
+  * Kotlin 1.9.0 and above. Support for experimental K2-compilation with `kotlin.experimental.tryK2=true`.
   * Ktor 2.1.2 and above.
   * Coroutines 1.7.0 and above.
   * AtomicFu 0.18.3 and above.
@@ -22,6 +22,7 @@
 * Minimum Gradle version: 6.8.3.
 * Minimum Android Gradle Plugin version: 4.1.3.
 * Minimum Android SDK: 16.
+* Minimum R8: 8.0.34.
 
 ### Internal
 * None.

Jenkinsfile

@@ -247,6 +247,7 @@ pipeline {
                     when { expression { runTests } }
                     steps {
                         testAndCollect("integration-tests/gradle-plugin-test", "integrationTest")
+                        testAndCollect("integration-tests/gradle-plugin-test", "-Pkotlin.experimental.tryK2=true integrationTest")
                     }
                 }
                 stage('Tests Android Sample App') {
@@ -268,6 +269,7 @@ pipeline {
                     when { expression { runTests } }
                     steps {
                         testAndCollect("examples/realm-java-compatibility", "connectedAndroidTest")
+                        testAndCollect("examples/realm-java-compatibility", "-Pkotlin.experimental.tryK2=true connectedAndroidTest")
                     }
                 }
                 stage('Track build metrics') {

buildSrc/src/main/kotlin/Config.kt

@@ -103,7 +103,7 @@ object Versions {
         const val buildToolsVersion = "33.0.0"
         const val buildTools = "7.3.1" // https://maven.google.com/web/index.html?q=gradle#com.android.tools.build:gradle
         const val ndkVersion = "23.2.8568313"
-        const val r8 = "4.0.48" // See https://developer.android.com/build/kotlin-support
+        const val r8 = "8.0.34" // See https://developer.android.com/build/kotlin-support
     }
     const val androidxBenchmarkPlugin = "1.2.0-alpha12" // https://maven.google.com/web/index.html#androidx.benchmark:androidx.benchmark.gradle.plugin
     const val androidxStartup = "1.1.1" // https://maven.google.com/web/index.html?q=startup#androidx.startup:startup-runtime
@@ -119,14 +119,14 @@ object Versions {
     const val coroutines = "1.7.0" // https://mvnrepository.com/artifact/org.jetbrains.kotlinx/kotlinx-coroutines-core
     const val datetime = "0.4.0" // https://github.com/Kotlin/kotlinx-datetime
     const val detektPlugin = "1.22.0-RC2" // https://github.com/detekt/detekt
-    const val dokka = "1.6.0" // https://github.com/Kotlin/dokka
+    const val dokka = "1.9.0" // https://github.com/Kotlin/dokka
     const val gradlePluginPublishPlugin = "0.15.0" // https://plugins.gradle.org/plugin/com.gradle.plugin-publish
     const val jmh = "1.34" // https://github.com/openjdk/jmh
     const val jmhPlugin = "0.6.6" // https://github.com/melix/jmh-gradle-plugin
     const val junit = "4.13.2" // https://mvnrepository.com/artifact/junit/junit
     const val kbson = "0.3.0" // https://github.com/mongodb/kbson
     // When updating the Kotlin version, also remember to update /examples/min-android-sample/build.gradle.kts
-    const val kotlin = "1.8.21" // https://github.com/JetBrains/kotlin and https://kotlinlang.org/docs/releases.html#release-details
+    const val kotlin = "1.9.0" // https://github.com/JetBrains/kotlin and https://kotlinlang.org/docs/releases.html#release-details
     const val kotlinJvmTarget = "1.8" // Which JVM bytecode version is kotlin compiled to.
     const val latestKotlin = "1.9.20-Beta" // https://kotlinlang.org/docs/eap.html#build-details
     const val kotlinCompileTesting = "1.5.0" // https://github.com/tschuchortdev/kotlin-compile-testing
@@ -136,7 +136,7 @@ object Versions {
     const val nexusPublishPlugin = "1.1.0" // https://github.com/gradle-nexus/publish-plugin
     const val okio = "3.2.0" // https://square.github.io/okio/#releases
     const val relinker = "1.4.5" // https://github.com/KeepSafe/ReLinker
-    const val serialization = "1.4.0" // https://kotlinlang.org/docs/releases.html#release-details
+    const val serialization = "1.6.0" // https://kotlinlang.org/docs/releases.html#release-details
     const val shadowJar =  "6.1.0" // https://mvnrepository.com/artifact/com.github.johnrengelman.shadow/com.github.johnrengelman.shadow.gradle.plugin?repo=gradle-plugins
     val sourceCompatibilityVersion = JavaVersion.VERSION_1_8 // Language level of any Java source code.
     val targetCompatibilityVersion = JavaVersion.VERSION_1_8 // Version of generated JVM bytecode from Java files.

examples/kmm-sample/shared/build.gradle.kts

@@ -64,7 +64,7 @@ kotlin {
                 implementation("com.google.android.material:material:1.2.0")
             }
         }
-        val androidTest by getting {
+        val androidInstrumentedTest by getting {
             dependencies {
                 implementation(kotlin("test-junit"))
                 implementation("junit:junit:4.12")

integration-tests/gradle-plugin-test/multi-platform/src/nativeTest/kotlin/io/realm/test/multiplatform/util/platform/PlatformUtils.kt

@@ -15,8 +15,11 @@
  * limitations under the License.
  */
 
+@file:OptIn(ExperimentalForeignApi::class)
+
 package io.realm.test.multiplatform.util.platform
 
+import kotlinx.cinterop.ExperimentalForeignApi
 import kotlinx.cinterop.cstr
 
 actual object PlatformUtils {

packages/cinterop/build.gradle.kts

@@ -271,6 +271,7 @@ kotlin {
         compilations.all {
             kotlinOptions {
                 freeCompilerArgs += listOf("-opt-in=kotlin.ExperimentalUnsignedTypes")
+                freeCompilerArgs += listOf("-opt-in=kotlinx.cinterop.ExperimentalForeignApi")
             }
         }
     }

packages/cinterop/src/nativeDarwin/kotlin/io/realm/kotlin/internal/interop/RealmInterop.kt

@@ -1985,7 +1985,7 @@ actual object RealmInterop {
                 realm_wrapper.realm_app_get_all_users(
                     app.cptr(),
                     null,
-                    0,
+                    0UL,
                     capacityCount.ptr
                 )
             )

packages/cinterop/src/nativeDarwinTest/kotlin/io/realm/kotlin/test/CinteropTest.kt

@@ -136,14 +136,14 @@ class CinteropTest {
             classes[0].apply {
                 name = "foo".cstr.ptr
                 primary_key = "".cstr.ptr
-                num_properties = 1.toULong()
-                num_computed_properties = 0.toULong()
+                num_properties = 1UL
+                num_computed_properties = 0UL
                 flags = RLM_CLASS_NORMAL.toInt()
             }
 
             val classProperties: CPointer<CPointerVarOf<CPointer<realm_property_info_t>>> =
                 cValuesOf(prop_1_1.ptr).ptr
-            val realmSchemaNew = realm_schema_new(classes, 1.toULong(), classProperties)
+            val realmSchemaNew = realm_schema_new(classes, 1UL, classProperties)
 
             assertNoError()
             assertTrue(
@@ -157,7 +157,7 @@ class CinteropTest {
             realm_config_set_path(config, "c_api_test.realm")
             realm_config_set_schema(config, realmSchemaNew)
             realm_config_set_schema_mode(config, realm_schema_mode_e.RLM_SCHEMA_MODE_AUTOMATIC)
-            realm_config_set_schema_version(config, 1)
+            realm_config_set_schema_version(config, 1UL)
 
             val realm: CPointer<realm_t>? = realm_open(config)
             assertEquals(1U, realm_get_num_classes(realm))

packages/library-base/build.gradle.kts

@@ -128,7 +128,12 @@ kotlin {
 // name and build type variant as a suffix, this default behaviour can cause mismatch at runtime https://github.com/realm/realm-kotlin/issues/621
 tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile>().configureEach {
     kotlinOptions {
-        freeCompilerArgs = listOf("-module-name", "io.realm.kotlin.library")
+        freeCompilerArgs += listOf("-module-name", "io.realm.kotlin.library")
+    }
+}
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinNativeCompile>().all {
+    kotlinOptions {
+        freeCompilerArgs += listOf("-opt-in=kotlinx.cinterop.ExperimentalForeignApi")
     }
 }
 

packages/library-sync/src/androidMain/kotlin/io/realm/kotlin/mongodb/internal/RealmSyncInitializer.kt

@@ -35,7 +35,7 @@ import io.realm.kotlin.log.RealmLog
  * An **initializer** for Sync specific functionality that does not fit into the `RealmInitializer`
  * in cinterop.o allow Realm to access context properties.
  */
-class RealmSyncInitializer : Initializer<Context> {
+internal class RealmSyncInitializer : Initializer<Context> {
 
     companion object {
         @Suppress("DEPRECATION") // Should only be called below API 21

packages/library-sync/src/commonMain/kotlin/io/realm/kotlin/mongodb/internal/MutableSubscriptionSetImpl.kt

@@ -87,7 +87,7 @@ internal class MutableSubscriptionSetImpl<T : BaseRealm>(
         return result
     }
 
-    @Suppress("invisible_member")
+    @Suppress("invisible_member", "invisible_reference")
     override fun <T : RealmObject> removeAll(type: KClass<T>): Boolean {
         var result = false
         val objectType = io.realm.kotlin.internal.platform.realmObjectCompanionOrThrow(type).`io_realm_kotlin_className`

packages/library-sync/src/commonMain/kotlin/io/realm/kotlin/mongodb/internal/SubscriptionImpl.kt

@@ -42,7 +42,7 @@ internal class SubscriptionImpl(
     // Trim the query to match the output of RealmQuery.description()
     override val queryDescription: String = RealmInterop.realm_sync_subscription_query_string(nativePointer).trim()
 
-    @Suppress("invisible_member")
+    @Suppress("invisible_member", "invisible_reference")
     override fun <T : RealmObject> asQuery(type: KClass<T>): RealmQuery<T> {
         // TODO Check for invalid combinations of Realm and type once we properly support
         // DynamicRealm

packages/library-sync/src/commonMain/kotlin/io/realm/kotlin/mongodb/internal/SyncConfigurationImpl.kt

@@ -222,7 +222,7 @@ internal class SyncConfigurationImpl(
                             initializerHelper.onSyncError(session, frozenAppPointer, error)
                         }
                     } catch (ex: Exception) {
-                        @Suppress("invisible_member")
+                        @Suppress("invisible_member", "invisible_reference")
                         RealmLog.error("Error thrown and ignored in `onManualResetFallback`: $ex")
                     }
                 } else {

packages/library-sync/src/commonMain/kotlin/io/realm/kotlin/mongodb/internal/SyncSessionImpl.kt

@@ -139,7 +139,7 @@ internal open class SyncSessionImpl(
         }
     }
 
-    @Suppress("invisible_member") // To be able to use RealmImpl.scopedFlow from library-base
+    @Suppress("invisible_member", "invisible_reference") // To be able to use RealmImpl.scopedFlow from library-base
     override fun connectionStateAsFlow(): Flow<ConnectionStateChange> = realm.scopedFlow {
         callbackFlow {
             val token: AtomicRef<Cancellable> = kotlinx.atomicfu.atomic(NO_OP_NOTIFICATION_TOKEN)

packages/plugin-compiler/src/main/kotlin/io/realm/kotlin/compiler/Identifiers.kt

@@ -26,6 +26,10 @@ import org.jetbrains.kotlin.name.Name
 internal object Names {
     const val REALM_SYNTHETIC_PROPERTY_PREFIX = "io_realm_kotlin_"
 
+    val REALM_OBJECT: Name = Name.identifier("RealmObject")
+    val EMBEDDED_REALM_OBJECT: Name = Name.identifier("EmbeddedRealmObject")
+    val ASYMMETRIC_REALM_OBJECT: Name = Name.identifier("AsymmetricRealmObject")
+
     val REALM_OBJECT_COMPANION_CLASS_MEMBER: Name =
         Name.identifier("${REALM_SYNTHETIC_PROPERTY_PREFIX}class")
     val REALM_OBJECT_COMPANION_CLASS_NAME_MEMBER: Name =
@@ -40,6 +44,9 @@ internal object Names {
         Name.identifier("${REALM_SYNTHETIC_PROPERTY_PREFIX}schema")
     val REALM_OBJECT_COMPANION_NEW_INSTANCE_METHOD =
         Name.identifier("${REALM_SYNTHETIC_PROPERTY_PREFIX}newInstance")
+    val REALM_OBJECT_TO_STRING_METHOD = Name.identifier("toString")
+    val REALM_OBJECT_EQUALS = Name.identifier("equals")
+    val REALM_OBJECT_HASH_CODE = Name.identifier("hashCode")
 
     val SET = Name.special("<set-?>")
 
@@ -90,11 +97,12 @@ internal object FqNames {
     val PACKAGE_KBSON = FqName("org.mongodb.kbson")
     val PACKAGE_KOTLIN_COLLECTIONS = FqName("kotlin.collections")
     val PACKAGE_KOTLIN_REFLECT = FqName("kotlin.reflect")
-    val PACKAGE_TYPES = FqName("io.realm.kotlin.types")
+    val PACKAGE_TYPES: FqName = FqName("io.realm.kotlin.types")
     val PACKAGE_REALM_INTEROP = FqName("io.realm.kotlin.internal.interop")
     val PACKAGE_REALM_INTERNAL = FqName("io.realm.kotlin.internal")
     val PACKAGE_MONGODB = FqName("io.realm.kotlin.mongodb")
     val PACKAGE_MONGODB_INTERNAL = FqName("io.realm.kotlin.mongodb.internal")
+    val APP_CONFIGURATION_BUILDER = FqName("AppConfiguration.Builder")
 }
 
 object ClassIds {
@@ -160,5 +168,5 @@ object ClassIds {
     val APP_IMPL = ClassId(PACKAGE_MONGODB_INTERNAL, Name.identifier("AppImpl"))
     val APP_CONFIGURATION = ClassId(PACKAGE_MONGODB, Name.identifier("AppConfiguration"))
     val APP_CONFIGURATION_IMPL = ClassId(PACKAGE_MONGODB_INTERNAL, Name.identifier("AppConfigurationImpl"))
-    val APP_CONFIGURATION_BUILDER = ClassId(FqName("io.realm.kotlin.mongodb.AppConfiguration"), FqName("Builder"), true)
+    val APP_CONFIGURATION_BUILDER = ClassId(PACKAGE_MONGODB, FqNames.APP_CONFIGURATION_BUILDER, false)
 }

packages/plugin-compiler/src/main/kotlin/io/realm/kotlin/compiler/IrUtils.kt

@@ -22,6 +22,10 @@ import io.realm.kotlin.compiler.ClassIds.EMBEDDED_OBJECT_INTERFACE
 import io.realm.kotlin.compiler.ClassIds.KOTLIN_COLLECTIONS_LISTOF
 import io.realm.kotlin.compiler.ClassIds.PERSISTED_NAME_ANNOTATION
 import io.realm.kotlin.compiler.ClassIds.REALM_OBJECT_INTERFACE
+import io.realm.kotlin.compiler.FqNames.PACKAGE_TYPES
+import io.realm.kotlin.compiler.Names.ASYMMETRIC_REALM_OBJECT
+import io.realm.kotlin.compiler.Names.EMBEDDED_REALM_OBJECT
+import io.realm.kotlin.compiler.Names.REALM_OBJECT
 import org.jetbrains.kotlin.backend.common.extensions.IrPluginContext
 import org.jetbrains.kotlin.backend.common.lower.DeclarationIrBuilder
 import org.jetbrains.kotlin.cli.common.messages.CompilerMessageLocationWithRange
@@ -30,9 +34,15 @@ import org.jetbrains.kotlin.com.intellij.openapi.util.text.StringUtil
 import org.jetbrains.kotlin.com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.com.intellij.psi.PsiElementVisitor
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
+import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.descriptors.DescriptorVisibilities
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
+import org.jetbrains.kotlin.fir.symbols.SymbolInternals
+import org.jetbrains.kotlin.fir.symbols.impl.FirClassSymbol
+import org.jetbrains.kotlin.fir.types.FirResolvedTypeRef
+import org.jetbrains.kotlin.fir.types.FirUserTypeRef
+import org.jetbrains.kotlin.fir.types.classId
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.IrBlockBodyBuilder
 import org.jetbrains.kotlin.ir.builders.IrBlockBuilder
@@ -105,6 +115,7 @@ import org.jetbrains.kotlin.name.CallableId
 import org.jetbrains.kotlin.name.ClassId
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.psi.stubs.elements.KtStubElementTypes
 import org.jetbrains.kotlin.psi.stubs.elements.KtStubElementTypes.SUPER_TYPE_LIST
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.types.KotlinType
@@ -141,10 +152,9 @@ val anyRealmObjectInterfacesFqNames = realmObjectInterfaceFqNames + realmEmbedde
 
 fun IrType.classIdOrFail(): ClassId = getClass()?.classId ?: error("Can't get classId of ${render()}")
 
-inline fun ClassDescriptor.hasInterfacePsi(interfaces: Set<String>): Boolean {
-    // Using PSI to find super types to avoid cyclic reference (see https://github.com/realm/realm-kotlin/issues/339)
+inline fun PsiElement.hasInterface(interfaces: Set<String>): Boolean {
     var hasRealmObjectAsSuperType = false
-    this.findPsi()?.acceptChildren(object : PsiElementVisitor() {
+    this.acceptChildren(object : PsiElementVisitor() {
         override fun visitElement(element: PsiElement) {
             if (element.node.elementType == SUPER_TYPE_LIST) {
                 // Check supertypes for classes with Embbeded/RealmObject as generics and remove
@@ -169,6 +179,10 @@ inline fun ClassDescriptor.hasInterfacePsi(interfaces: Set<String>): Boolean {
 
     return hasRealmObjectAsSuperType
 }
+inline fun ClassDescriptor.hasInterfacePsi(interfaces: Set<String>): Boolean {
+    // Using PSI to find super types to avoid cyclic reference (see https://github.com/realm/realm-kotlin/issues/339)
+    return this.findPsi()?.hasInterface(interfaces) ?: false
+}
 
 // Do to the way PSI works, it can be a bit tricky to uniquely identify when the Realm Kotlin
 // RealmObject interface is used. For that reason, once we have determined a match for RealmObject,
@@ -186,6 +200,34 @@ val ClassDescriptor.isEmbeddedRealmObject: Boolean
 val ClassDescriptor.isBaseRealmObject: Boolean
     get() = this.hasInterfacePsi(realmObjectPsiNames + embeddedRealmObjectPsiNames + asymmetricRealmObjectPsiNames) && !this.hasInterfacePsi(realmJavaObjectPsiNames)
 
+val realmObjectTypes: Set<Name> = setOf(REALM_OBJECT, EMBEDDED_REALM_OBJECT, ASYMMETRIC_REALM_OBJECT)
+val realmObjectClassIds = realmObjectTypes.map { name -> ClassId(PACKAGE_TYPES, name) }
+
+// This is the K2 equivalent of our PSI hack to determine if a symbol has a RealmObject base class.
+// There is currently no way to determine this within the resolved type system and there is
+// probably no such option around the corner.
+// https://kotlinlang.slack.com/archives/C03PK0PE257/p1694599154558669
+@OptIn(SymbolInternals::class)
+val FirClassSymbol<*>.isBaseRealmObject: Boolean
+    get() = this.classKind == ClassKind.CLASS &&
+        this.fir.superTypeRefs.any { typeRef ->
+            when (typeRef) {
+                // In SUPERTYPES stage
+                is FirUserTypeRef -> {
+                    typeRef.qualifier.last().name in realmObjectTypes &&
+                        // Disregard constructor invocations as that means that it is a Realm Java class
+                        !(
+                            typeRef.source?.run { treeStructure.getParent(lighterASTNode) }
+                                ?.tokenType?.let { it == KtStubElementTypes.CONSTRUCTOR_CALLEE }
+                                ?: false
+                            )
+                }
+                // After SUPERTYPES stage
+                is FirResolvedTypeRef -> typeRef.type.classId in realmObjectClassIds
+                else -> false
+            }
+        }
+
 // JetBrains already have a method `fun IrAnnotationContainer.hasAnnotation(symbol: IrClassSymbol)`
 // It is unclear exactly what the difference is and how to get a ClassSymbol from a ClassId,
 // so for now just work around it.

packages/plugin-compiler/src/main/kotlin/io/realm/kotlin/compiler/RealmModelSyntheticMethodsExtension.kt

@@ -51,8 +51,8 @@ class RealmModelSyntheticMethodsExtension : SyntheticResolveExtension {
             !isNestedInRealmModelClass(thisDescriptor) && /* do not override nested class methods */
             result.isEmpty() /* = no method has been declared in the current class */
         ) {
-            when (name.identifier) {
-                "toString" -> {
+            when (name) {
+                Names.REALM_OBJECT_TO_STRING_METHOD -> {
                     result.add(
                         createMethod(
                             classDescriptor = thisDescriptor,
@@ -62,7 +62,7 @@ class RealmModelSyntheticMethodsExtension : SyntheticResolveExtension {
                         )
                     )
                 }
-                "equals" -> {
+                Names.REALM_OBJECT_EQUALS -> {
                     result.add(
                         createMethod(
                             classDescriptor = thisDescriptor,
@@ -72,7 +72,7 @@ class RealmModelSyntheticMethodsExtension : SyntheticResolveExtension {
                         )
                     )
                 }
-                "hashCode" -> {
+                Names.REALM_OBJECT_HASH_CODE -> {
                     result.add(
                         createMethod(
                             classDescriptor = thisDescriptor,