Parcelable: Give priority to Parcelable type over objects and enums (KT-20021)

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

@@ -167,12 +167,6 @@ interface ParcelSerializer {
                         Method("writeException"),
                         Method("readException")))
 
-                // 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))
-
                 asmType.isFileDescriptor() -> wrapToNullAwareIfNeeded(type, NullCompliantObjectParcelSerializer(asmType,
                         Method("writeRawFileDescriptor"),
                         Method("readRawFileDescriptor")))
@@ -197,6 +191,12 @@ 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/testData/parcel/box/kt20021.kt

@@ -0,0 +1,45 @@
+// WITH_RUNTIME
+
+@file:JvmName("TestKt")
+package test
+
+import kotlinx.android.parcel.*
+import android.os.Parcel
+import android.os.Parcelable
+import java.util.Arrays
+
+enum class ParcelableEnum : Parcelable {
+    ONE, TWO, THREE;
+
+    override fun writeToParcel(parcel: Parcel, flags: Int) {
+        parcel.writeInt(ordinal)
+    }
+
+    override fun describeContents() = 0
+
+    companion object {
+        @JvmField
+        val CREATOR: Parcelable.Creator<ParcelableEnum> = object : Parcelable.Creator<ParcelableEnum> {
+            override fun createFromParcel(parcel: Parcel) = ParcelableEnum.ONE
+            override fun newArray(size: Int) = arrayOfNulls<ParcelableEnum>(size)
+        }
+    }
+}
+
+@Parcelize
+class Test(val parcelableEnum: ParcelableEnum): Parcelable
+
+fun box() = parcelTest { parcel ->
+    val first = Test(ParcelableEnum.THREE)
+
+    first.writeToParcel(parcel, 0)
+
+    val bytes = parcel.marshall()
+    parcel.unmarshall(bytes, 0, bytes.size)
+
+    val first2 = readFromParcel<Test>(parcel)
+
+    assert(first.parcelableEnum == ParcelableEnum.THREE)
+    assert(first2.parcelableEnum == ParcelableEnum.ONE)
+    assert(first != first2)
+}

plugins/plugins-tests/tests/org/jetbrains/kotlin/android/parcel/ParcelBoxTest.kt

@@ -50,4 +50,5 @@ class ParcelBoxTest : AbstractParcelBoxTest() {
     fun testKt19747() = doTest("kt19747")
     fun testKt19747_2() = doTest("kt19747_2")
     fun test20002() = doTest("kt20002")
+    fun test20021() = doTest("kt20021")
 }