Extension points for synthetic function contributions

Pass real type arguments serializers to runtime lib

plugins/kotlin-serialization/kotlin-serialization-compiler/src/org/jetbrains/kotlinx/serialization/compiler/backend/js/SerializerJsTranslator.kt

@@ -123,9 +123,12 @@ class SerializerJsTranslator(declaration: KtPureClassOrObject,
         val serialClassDescRef = JsNameRef(context.getNameForDescriptor(serialDescPropertyDescriptor!!), JsThisRef())
 
         // output.writeBegin(desc, [])
+        val typeParams = serializableDescriptor.declaredTypeParameters.mapIndexed { idx, _ ->
+            JsNameRef(context.scope().declareName("$typeArgPrefix$idx"), JsThisRef())
+        }
         val call = JsInvocation(JsNameRef(wBeginFunc, JsNameRef(jsFun.parameters[0].name)),
                                 serialClassDescRef,
-                                JsArrayLiteral())
+                                JsArrayLiteral(typeParams))
         val objRef = JsNameRef(jsFun.parameters[1].name)
         // output = output.writeBegin...
         val localOutputName = jsFun.scope.declareFreshName("output")
@@ -229,10 +232,13 @@ class SerializerJsTranslator(declaration: KtPureClassOrObject,
         +JsVars(localProps.map { JsVars.JsVar(it.name) }, true)
 
         //input = input.readBegin(...)
+        val typeParams = serializableDescriptor.declaredTypeParameters.mapIndexed { idx, _ ->
+            JsNameRef(context.scope().declareName("$typeArgPrefix$idx"), JsThisRef())
+        }
         val inputVar = JsNameRef(jsFun.scope.declareFreshName("input"))
         val readBeginF = inputClass.getFuncDesc("readBegin").single()
         val call = JsInvocation(JsNameRef(context.getNameForDescriptor(readBeginF), JsNameRef(jsFun.parameters[0].name)),
-                                serialClassDescRef, JsArrayLiteral())
+                                serialClassDescRef, JsArrayLiteral(typeParams))
         +JsVars(JsVars.JsVar(inputVar.name, call))
 
         // while(true) {

plugins/kotlin-serialization/kotlin-serialization-compiler/src/org/jetbrains/kotlinx/serialization/compiler/backend/jvm/SerializerCodegenImpl.kt

@@ -140,8 +140,7 @@ class SerializerCodegenImpl(
             // output = output.writeBegin(classDesc, new KSerializer[0])
             load(outputVar, kOutputType)
             load(descVar, descType)
-            iconst(0)
-            newarray(kSerializerType) // todo: use some predefined empty array
+            genArrayOfTypeParametersSerializers()
             invokevirtual(kOutputType.internalName, "writeBegin",
                           "(" + descType.descriptor + kSerializerArrayType.descriptor +
                           ")" + kOutputType.descriptor, false)
@@ -184,6 +183,19 @@ class SerializerCodegenImpl(
         }
     }
 
+    internal fun InstructionAdapter.genArrayOfTypeParametersSerializers() {
+        val size = serializableDescriptor.declaredTypeParameters.size
+        iconst(size)
+        newarray(kSerializerType) // todo: use some predefined empty array, if size is 0
+        for (i in 0 until size) {
+            dup() // array
+            iconst(i) // index
+            load(0, kSerializerType) // this.serialTypeI
+            getfield(codegen.typeMapper.mapClass(codegen.descriptor).internalName, "$typeArgPrefix$i", kSerializerType.descriptor)
+            astore(kSerializerType)
+        }
+    }
+
     override fun generateLoad(
             function: FunctionDescriptor
     ) {
@@ -218,8 +230,7 @@ class SerializerCodegenImpl(
             // input = input.readBegin(classDesc, new KSerializer[0])
             load(inputVar, kInputType)
             load(descVar, descType)
-            iconst(0)
-            newarray(kSerializerType) // todo: use some predefined empty array
+            genArrayOfTypeParametersSerializers()
             invokevirtual(kInputType.internalName, "readBegin",
                           "(" + descType.descriptor + kSerializerArrayType.descriptor +
                           ")" + kInputType.descriptor, false)

plugins/kotlin-serialization/kotlin-serialization-compiler/src/org/jetbrains/kotlinx/serialization/compiler/extensions/SerializationResolveExtension.kt

@@ -26,6 +26,7 @@ import org.jetbrains.kotlin.resolve.lazy.LazyClassContext
 import org.jetbrains.kotlin.resolve.lazy.declarations.ClassMemberDeclarationProvider
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlinx.serialization.compiler.resolve.KSerializerDescriptorResolver
+import org.jetbrains.kotlinx.serialization.compiler.resolve.getSerializableClassDescriptorByCompanion
 import org.jetbrains.kotlinx.serialization.compiler.resolve.isInternalSerializable
 import org.jetbrains.kotlinx.serialization.compiler.resolve.serialInfoFqName
 import java.util.*
@@ -37,6 +38,12 @@ class SerializationResolveExtension : SyntheticResolveExtension {
         else -> listOf()
     }
 
+    override fun getSyntheticFunctionNames(thisDescriptor: ClassDescriptor): List<Name> = when {
+        thisDescriptor.isCompanionObject && getSerializableClassDescriptorByCompanion(thisDescriptor) != null ->
+            listOf(KSerializerDescriptorResolver.SERIALIZER_PROVIDER_NAME)
+        else -> emptyList()
+    }
+
     override fun generateSyntheticClasses(thisDescriptor: ClassDescriptor, name: Name, ctx: LazyClassContext, declarationProvider: ClassMemberDeclarationProvider, result: MutableSet<ClassDescriptor>) {
         if (thisDescriptor.annotations.hasAnnotation(serialInfoFqName) && name == KSerializerDescriptorResolver.IMPL_NAME)
             result.add(KSerializerDescriptorResolver.addSerialInfoImplClass(thisDescriptor, declarationProvider, ctx))