Parcelize: Support objects and enums (#KT-22576)

plugins/android-extensions/android-extensions-compiler/src/org/jetbrains/kotlin/android/parcel/ParcelableClinitClassBuilderInterceptorExtension.kt

@@ -23,7 +23,7 @@ import org.jetbrains.kotlin.codegen.ClassBuilderFactory
 import org.jetbrains.kotlin.codegen.DelegatingClassBuilder
 import org.jetbrains.kotlin.codegen.extensions.ClassBuilderInterceptorExtension
 import org.jetbrains.kotlin.diagnostics.DiagnosticSink
-import org.jetbrains.kotlin.psi.KtClass
+import org.jetbrains.kotlin.psi.KtClassOrObject
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.jvm.diagnostics.JvmDeclarationOrigin
 import org.jetbrains.org.objectweb.asm.*
@@ -68,7 +68,7 @@ class ParcelableClinitClassBuilderInterceptorExtension : ClassBuilderInterceptor
             internal val delegateClassBuilder: ClassBuilder,
             val bindingContext: BindingContext
     ) : DelegatingClassBuilder() {
-        private var currentClass: KtClass? = null
+        private var currentClass: KtClassOrObject? = null
         private var currentClassName: String? = null
         private var isClinitGenerated = false
 
@@ -83,7 +83,7 @@ class ParcelableClinitClassBuilderInterceptorExtension : ClassBuilderInterceptor
                 superName: String,
                 interfaces: Array<out String>
         ) {
-            if (origin is KtClass) {
+            if (origin is KtClassOrObject) {
                 currentClass = origin
             } else {
                 currentClass = null

plugins/android-extensions/android-extensions-compiler/src/org/jetbrains/kotlin/android/parcel/ParcelableCodegenExtension.kt

@@ -60,6 +60,8 @@ open class ParcelableCodegenExtension : ExpressionCodegenExtension {
     private companion object {
         private val FILE_DESCRIPTOR_FQNAME = FqName(FileDescriptor::class.java.canonicalName)
         private val CREATOR_NAME = Name.identifier("CREATOR")
+
+        private val ALLOWED_CLASS_KINDS = listOf(ClassKind.CLASS, ClassKind.OBJECT, ClassKind.ENUM_CLASS)
     }
 
     protected open fun isExperimental(element: KtElement) = true
@@ -74,7 +76,7 @@ open class ParcelableCodegenExtension : ExpressionCodegenExtension {
         val sourceElement = (codegen.myClass as? KtClassOrObject) ?: return
         if (!isExperimental(sourceElement)) return
 
-        if (parcelableClass.kind != ClassKind.CLASS && parcelableClass.kind != ClassKind.OBJECT) return
+        if (parcelableClass.kind !in ALLOWED_CLASS_KINDS) return
 
         val propertiesToSerialize = getPropertiesToSerialize(codegen, parcelableClass)
 
@@ -163,15 +165,25 @@ open class ParcelableCodegenExtension : ExpressionCodegenExtension {
 
                 val globalContext = ParcelSerializer.ParcelSerializerContext(codegen.typeMapper, containerAsmType, emptyList(), frameMap)
 
-                for ((fieldName, type, parcelers) in properties) {
+                if (properties.isEmpty()) {
-                    val asmType = codegen.typeMapper.mapType(type)
+                    val entityType = this@writeWriteToParcel.defaultType
-
+                    val asmType = codegen.state.typeMapper.mapType(entityType)
+                    val serializer = ParcelSerializer.get(entityType, asmType, globalContext, strict = true)
                     v.load(1, parcelAsmType)
                     v.load(0, containerAsmType)
-                    v.getfield(containerAsmType.internalName, fieldName, asmType.descriptor)
-
-                    val serializer = ParcelSerializer.get(type, asmType, globalContext.copy(typeParcelers = parcelers))
                     serializer.writeValue(v)
+                } else {
+                    for ((fieldName, type, parcelers) in properties) {
+                        val asmType = codegen.typeMapper.mapType(type)
+
+                        v.load(1, parcelAsmType)
+                        v.load(0, containerAsmType)
+                        v.getfield(containerAsmType.internalName, fieldName, asmType.descriptor)
+
+                        val serializer = ParcelSerializer.get(type, asmType, globalContext.copy(typeParcelers = parcelers))
+                        serializer.writeValue(v)
+                    }
+
                 }
             }
 
@@ -253,16 +265,24 @@ open class ParcelableCodegenExtension : ExpressionCodegenExtension {
 
                 val globalContext = ParcelSerializer.ParcelSerializerContext(codegen.typeMapper, containerAsmType, emptyList(), frameMap)
 
-                for ((_, type, parcelers) in properties) {
+                if (properties.isEmpty()) {
-                    val asmType = codegen.typeMapper.mapType(type)
+                    val entityType = parcelableClass.defaultType
-                    asmConstructorParameters.append(asmType.descriptor)
+                    val asmType = codegen.state.typeMapper.mapType(entityType)
-
+                    val serializer = ParcelSerializer.get(entityType, asmType, globalContext, strict = true)
-                    val serializer = ParcelSerializer.get(type, asmType, globalContext.copy(typeParcelers = parcelers))
                     v.load(1, parcelAsmType)
                     serializer.readValue(v)
-                }
+                } else {
+                    for ((_, type, parcelers) in properties) {
+                        val asmType = codegen.typeMapper.mapType(type)
+                        asmConstructorParameters.append(asmType.descriptor)
 
-                v.invokespecial(containerAsmType.internalName, "<init>", "($asmConstructorParameters)V", false)
+                        val serializer = ParcelSerializer.get(type, asmType, globalContext.copy(typeParcelers = parcelers))
+                        v.load(1, parcelAsmType)
+                        serializer.readValue(v)
+                    }
+
+                    v.invokespecial(containerAsmType.internalName, "<init>", "($asmConstructorParameters)V", false)
+                }
             }
 
             v.areturn(containerAsmType)

plugins/android-extensions/android-extensions-compiler/src/org/jetbrains/kotlin/android/parcel/ParcelableDeclarationChecker.kt

@@ -109,14 +109,13 @@ class ParcelableDeclarationChecker : DeclarationChecker {
     ) {
         if (!descriptor.isParcelize) return
 
-        if (declaration !is KtClass || (declaration.isAnnotation() || declaration.isInterface())) {
+        if (declaration !is KtClassOrObject) {
-            val reportElement = (declaration as? KtClassOrObject)?.nameIdentifier ?: declaration
+            diagnosticHolder.reportFromPlugin(ErrorsAndroid.PARCELABLE_SHOULD_BE_CLASS.on(declaration), DefaultErrorMessagesAndroid)
-            diagnosticHolder.reportFromPlugin(ErrorsAndroid.PARCELABLE_SHOULD_BE_CLASS.on(reportElement), DefaultErrorMessagesAndroid)
             return
         }
 
-        if (declaration.isEnum()) {
+        if (declaration is KtClass && (declaration.isAnnotation() || declaration.isInterface())) {
-            val reportElement = (declaration as? KtClass)?.nameIdentifier ?: declaration
+            val reportElement = declaration.nameIdentifier ?: declaration
             diagnosticHolder.reportFromPlugin(ErrorsAndroid.PARCELABLE_SHOULD_BE_CLASS.on(reportElement), DefaultErrorMessagesAndroid)
             return
         }
@@ -133,7 +132,7 @@ class ParcelableDeclarationChecker : DeclarationChecker {
             diagnosticHolder.reportFromPlugin(ErrorsAndroid.PARCELABLE_SHOULD_BE_INSTANTIABLE.on(sealedOrAbstract), DefaultErrorMessagesAndroid)
         }
 
-        if (declaration.isInner()) {
+        if (declaration is KtClass && declaration.isInner()) {
             val reportElement = declaration.modifierList?.getModifier(KtTokens.INNER_KEYWORD) ?: declaration.nameIdentifier ?: declaration
             diagnosticHolder.reportFromPlugin(ErrorsAndroid.PARCELABLE_CANT_BE_INNER_CLASS.on(reportElement), DefaultErrorMessagesAndroid)
         }

plugins/android-extensions/android-extensions-compiler/src/org/jetbrains/kotlin/android/parcel/serializers/ParcelSerializer.kt

@@ -230,6 +230,12 @@ interface ParcelSerializer {
                         Method("writeRawFileDescriptor"),
                         Method("readRawFileDescriptor")))
 
+                // Write at least a nullability byte.
+                // We don't want parcel to be empty in case if all constructor parameters are objects
+                type.isNamedObject() -> NullAwareParcelSerializerWrapper(ObjectParcelSerializer(asmType, type, typeMapper))
+
+                type.isEnum() -> wrapToNullAwareIfNeeded(type, EnumParcelSerializer(asmType))
+
                 type.isParcelable() -> {
                     val clazz = type.constructor.declarationDescriptor as? ClassDescriptor
                     if (clazz != null && clazz.modality == Modality.FINAL && clazz.source is PsiSourceElement) {
@@ -257,12 +263,6 @@ interface ParcelSerializer {
                     }
                 }
 
-                // Write at least a nullability byte.
-                // We don't want parcel to be empty in case if all constructor parameters are objects
-                type.isNamedObject() -> NullAwareParcelSerializerWrapper(ObjectParcelSerializer(asmType, type, typeMapper))
-
-                type.isEnum() -> wrapToNullAwareIfNeeded(type, EnumParcelSerializer(asmType))
-
                 type.isSerializable() -> NullCompliantObjectParcelSerializer(asmType,
                         Method("writeSerializable", "(Ljava/io/Serializable;)V"),
                         Method("readSerializable", "()Ljava/io/Serializable;"))

plugins/android-extensions/android-extensions-compiler/test/org/jetbrains/android/parcel/ParcelBoxTest.kt

@@ -54,6 +54,7 @@ class ParcelBoxTest : AbstractParcelBoxTest() {
     fun testCustomSerializerWriteWith() = doTest("customSerializerWriteWith")
     fun testCustomSerializerBoxing() = doTest("customSerializerBoxing")
     fun testKt20717() = doTest("kt20717")
+    fun testEnumObject() = doTest("enumObject")
 }
 
 class ParcelBoxTestWithSerializableLikeExtension : AbstractParcelBoxTest() {

plugins/android-extensions/android-extensions-compiler/testData/parcel/box/enumObject.kt

@@ -0,0 +1,37 @@
+// WITH_RUNTIME
+
+@file:JvmName("TestKt")
+package test
+
+import kotlinx.android.parcel.*
+import android.os.Parcel
+import android.os.Parcelable
+
+@Parcelize
+enum class Color : Parcelable { BLACK, WHITE }
+
+@Parcelize
+object Obj : Parcelable
+
+fun box() = parcelTest { parcel ->
+    val black = Color.BLACK
+    val obj = Obj
+
+    black.writeToParcel(parcel, 0)
+    obj.writeToParcel(parcel, 0)
+
+    println(black)
+    println(obj)
+
+    val bytes = parcel.marshall()
+    parcel.unmarshall(bytes, 0, bytes.size)
+
+    val black2 = readFromParcel<Color>(parcel)
+    val obj2 = readFromParcel<Obj>(parcel)
+
+    println(black2)
+    println(obj2)
+
+    assert(black2 == black)
+    assert(obj2 != null)
+}

plugins/android-extensions/android-extensions-idea/testData/android/parcel/checker/modality.kt

@@ -24,7 +24,7 @@ class Outer {
 
 fun foo() {
     @Parcelize
-    <error descr="[PLUGIN_ERROR] 'Parcelable' should be a class">object</error> : Parcelable {}
+    <error descr="[PLUGIN_ERROR] 'Parcelable' can't be a local class">object</error> : Parcelable {}
 
     @Parcelize
     class <error descr="[PLUGIN_ERROR] 'Parcelable' can't be a local class"><error descr="[PLUGIN_ERROR] No 'Parcelable' supertype">Local</error></error> {}

plugins/android-extensions/android-extensions-idea/testData/android/parcel/checker/wrongAnnotationTarget.kt

@@ -7,17 +7,17 @@ import android.os.Parcelable
 interface <error descr="[PLUGIN_ERROR] 'Parcelable' should be a class">Intf</error> : Parcelable
 
 @Parcelize
-object <error descr="[PLUGIN_ERROR] 'Parcelable' should be a class">Obj</error>
+object <error descr="[PLUGIN_ERROR] No 'Parcelable' supertype">Obj</error>
 
 class A {
     @Parcelize
-    companion <error descr="[PLUGIN_ERROR] 'Parcelable' should be a class">object</error> {
+    companion <error descr="[PLUGIN_ERROR] No 'Parcelable' supertype">object</error> {
         fun foo() {}
     }
 }
 
 @Parcelize
-enum class <error descr="[PLUGIN_ERROR] 'Parcelable' should be a class">Enum</error> {
+enum class <error descr="[PLUGIN_ERROR] No 'Parcelable' supertype">Enum</error> {
     WHITE, BLACK
 }