Reflect: Handle methods with inline class default parameters

compiler/fir/fir2ir/tests/org/jetbrains/kotlin/codegen/ir/FirBlackBoxCodegenTestGenerated.java

@@ -23660,6 +23660,11 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
                 runTest("compiler/testData/codegen/box/reflection/callBy/extensionFunction.kt");
             }
 
+            @TestMetadata("inlineClassDefaultArguments.kt")
+            public void testInlineClassDefaultArguments() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/inlineClassDefaultArguments.kt");
+            }
+
             @TestMetadata("inlineClassFunctionsAndConstructors.kt")
             public void testInlineClassFunctionsAndConstructors() throws Exception {
                 runTest("compiler/testData/codegen/box/reflection/callBy/inlineClassFunctionsAndConstructors.kt");

compiler/testData/codegen/box/reflection/callBy/inlineClassDefaultArguments.kt

@@ -0,0 +1,10 @@
+// IGNORE_BACKEND: JS_IR, JS, NATIVE
+// WITH_REFLECT
+
+inline class A(val x: Int)
+
+fun test(x: A = A(0)) = "OK"
+
+fun box(): String {
+    return (::test).callBy(mapOf())
+}

compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java

@@ -25246,6 +25246,11 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
                 runTest("compiler/testData/codegen/box/reflection/callBy/extensionFunction.kt");
             }
 
+            @TestMetadata("inlineClassDefaultArguments.kt")
+            public void testInlineClassDefaultArguments() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/inlineClassDefaultArguments.kt");
+            }
+
             @TestMetadata("inlineClassFunctionsAndConstructors.kt")
             public void testInlineClassFunctionsAndConstructors() throws Exception {
                 runTest("compiler/testData/codegen/box/reflection/callBy/inlineClassFunctionsAndConstructors.kt");

compiler/tests/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java

@@ -24063,6 +24063,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
                 runTest("compiler/testData/codegen/box/reflection/callBy/extensionFunction.kt");
             }
 
+            @TestMetadata("inlineClassDefaultArguments.kt")
+            public void testInlineClassDefaultArguments() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/inlineClassDefaultArguments.kt");
+            }
+
             @TestMetadata("inlineClassFunctionsAndConstructors.kt")
             public void testInlineClassFunctionsAndConstructors() throws Exception {
                 runTest("compiler/testData/codegen/box/reflection/callBy/inlineClassFunctionsAndConstructors.kt");

compiler/tests/org/jetbrains/kotlin/codegen/ir/IrBlackBoxCodegenTestGenerated.java

@@ -23660,6 +23660,11 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
                 runTest("compiler/testData/codegen/box/reflection/callBy/extensionFunction.kt");
             }
 
+            @TestMetadata("inlineClassDefaultArguments.kt")
+            public void testInlineClassDefaultArguments() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/inlineClassDefaultArguments.kt");
+            }
+
             @TestMetadata("inlineClassFunctionsAndConstructors.kt")
             public void testInlineClassFunctionsAndConstructors() throws Exception {
                 runTest("compiler/testData/codegen/box/reflection/callBy/inlineClassFunctionsAndConstructors.kt");

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

@@ -132,7 +132,9 @@ internal abstract class KCallableImpl<out R> : KCallable<R> {
                     arguments.add(args[parameter])
                 }
                 parameter.isOptional -> {
-                    arguments.add(defaultPrimitiveValue(parameter.type.javaType))
+                    // For inline class types, the javaType refers to the underlying type of the inline class,
+                    // but we have to pass null in order to mark the argument as absent for InlineClassAwareCaller.
+                    arguments.add(if (parameter.type.isInlineClassType) null else defaultPrimitiveValue(parameter.type.javaType))
                     mask = mask or (1 shl (index % Integer.SIZE))
                     anyOptional = true
                 }
@@ -192,22 +194,6 @@ internal abstract class KCallableImpl<out R> : KCallable<R> {
         }
     }
 
-    private fun defaultPrimitiveValue(type: Type): Any? =
-        if (type is Class<*> && type.isPrimitive) {
-            when (type) {
-                Boolean::class.java -> false
-                Char::class.java -> 0.toChar()
-                Byte::class.java -> 0.toByte()
-                Short::class.java -> 0.toShort()
-                Int::class.java -> 0
-                Float::class.java -> 0f
-                Long::class.java -> 0L
-                Double::class.java -> 0.0
-                Void.TYPE -> throw IllegalStateException("Parameter with void type is illegal")
-                else -> throw UnsupportedOperationException("Unknown primitive: $type")
-            }
-        } else null
-
     private fun defaultEmptyArray(type: KType): Any =
         type.jvmErasure.java.run {
             if (isArray) ReflectArray.newInstance(componentType, 0)

core/reflection.jvm/src/kotlin/reflect/jvm/internal/calls/InlineClassAwareCaller.kt

@@ -17,6 +17,7 @@ import java.lang.reflect.Member
 import java.lang.reflect.Method
 import java.lang.reflect.Type
 import kotlin.reflect.jvm.internal.KotlinReflectionInternalError
+import kotlin.reflect.jvm.internal.defaultPrimitiveValue
 import kotlin.reflect.jvm.internal.toJavaClass
 
 /**
@@ -127,9 +128,15 @@ internal class InlineClassAwareCaller<out M : Member?>(
             val method = unbox[index]
             val arg = args[index]
             // Note that arg may be null in case we're calling a $default method and it's an optional parameter of an inline class type
-            unboxed[index] =
+            unboxed[index] = if (method != null) {
-                    if (method != null && arg != null) method.invoke(arg)
+                if (arg != null) {
-                    else arg
+                    method.invoke(arg)
+                } else {
+                    defaultPrimitiveValue(method.returnType)
+                }
+            } else {
+                arg
+            }
         }
 
         val result = caller.call(unboxed)

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

@@ -46,6 +46,9 @@ import org.jetbrains.kotlin.descriptors.runtime.components.tryLoadClass
 import org.jetbrains.kotlin.descriptors.runtime.structure.ReflectJavaAnnotation
 import org.jetbrains.kotlin.descriptors.runtime.structure.ReflectJavaClass
 import org.jetbrains.kotlin.descriptors.runtime.structure.safeClassLoader
+import org.jetbrains.kotlin.resolve.isInlineClassType
+import java.lang.reflect.Type
+import kotlin.reflect.KType
 
 internal val JVM_STATIC = FqName("kotlin.jvm.JvmStatic")
 
@@ -195,3 +198,22 @@ internal fun <M : MessageLite, D : CallableDescriptor> deserializeToDescriptor(
     )
     return MemberDeserializer(context).createDescriptor(proto)
 }
+
+internal val KType.isInlineClassType: Boolean
+    get() = (this as? KTypeImpl)?.type?.isInlineClassType() == true
+
+internal fun defaultPrimitiveValue(type: Type): Any? =
+    if (type is Class<*> && type.isPrimitive) {
+        when (type) {
+            Boolean::class.java -> false
+            Char::class.java -> 0.toChar()
+            Byte::class.java -> 0.toByte()
+            Short::class.java -> 0.toShort()
+            Int::class.java -> 0
+            Float::class.java -> 0f
+            Long::class.java -> 0L
+            Double::class.java -> 0.0
+            Void.TYPE -> throw IllegalStateException("Parameter with void type is illegal")
+            else -> throw UnsupportedOperationException("Unknown primitive: $type")
+        }
+    } else null

js/js.tests/test/org/jetbrains/kotlin/js/test/ir/semantics/IrJsCodegenBoxTestGenerated.java

@@ -19911,6 +19911,11 @@ public class IrJsCodegenBoxTestGenerated extends AbstractIrJsCodegenBoxTest {
                 runTest("compiler/testData/codegen/box/reflection/callBy/extensionFunction.kt");
             }
 
+            @TestMetadata("inlineClassDefaultArguments.kt")
+            public void testInlineClassDefaultArguments() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/inlineClassDefaultArguments.kt");
+            }
+
             @TestMetadata("inlineClassFunctionsAndConstructors.kt")
             public void testInlineClassFunctionsAndConstructors() throws Exception {
                 runTest("compiler/testData/codegen/box/reflection/callBy/inlineClassFunctionsAndConstructors.kt");

js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/JsCodegenBoxTestGenerated.java

@@ -19971,6 +19971,11 @@ public class JsCodegenBoxTestGenerated extends AbstractJsCodegenBoxTest {
                 runTest("compiler/testData/codegen/box/reflection/callBy/extensionFunction.kt");
             }
 
+            @TestMetadata("inlineClassDefaultArguments.kt")
+            public void testInlineClassDefaultArguments() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/inlineClassDefaultArguments.kt");
+            }
+
             @TestMetadata("inlineClassFunctionsAndConstructors.kt")
             public void testInlineClassFunctionsAndConstructors() throws Exception {
                 runTest("compiler/testData/codegen/box/reflection/callBy/inlineClassFunctionsAndConstructors.kt");