Make anonymous classes for callable references synthetic

#KT-28453 Fixed

compiler/backend/src/org/jetbrains/kotlin/codegen/AsmUtil.java

@@ -435,6 +435,11 @@ public class AsmUtil {
         return InlineUtil.isInlineOrContainingInline(descriptor.getContainingDeclaration()) ? ACC_PUBLIC : NO_FLAG_PACKAGE_PRIVATE;
     }
 
+    public static int getSyntheticAccessFlagForLambdaClass(@NotNull ClassDescriptor descriptor) {
+        return descriptor instanceof SyntheticClassDescriptorForLambda &&
+               ((SyntheticClassDescriptorForLambda) descriptor).isCallableReference() ? ACC_SYNTHETIC : 0;
+    }
+
     public static int calculateInnerClassAccessFlags(@NotNull ClassDescriptor innerClass) {
         int visibility =
                 innerClass instanceof SyntheticClassDescriptorForLambda
@@ -443,6 +448,7 @@ public class AsmUtil {
                   ? ACC_PUBLIC
                   : getVisibilityAccessFlag(innerClass);
         return visibility |
+               getSyntheticAccessFlagForLambdaClass(innerClass) |
                innerAccessFlagsForModalityAndKind(innerClass) |
                (innerClass.isInner() ? 0 : ACC_STATIC);
     }

compiler/backend/src/org/jetbrains/kotlin/codegen/ClosureCodegen.java

@@ -142,13 +142,14 @@ public class ClosureCodegen extends MemberCodegen<KtElement> {
             sw.writeInterfaceEnd();
         }
 
-        v.defineClass(element,
+        v.defineClass(
-                      state.getClassFileVersion(),
+                element,
-                      ACC_FINAL | ACC_SUPER | visibilityFlag,
+                state.getClassFileVersion(),
-                      asmType.getInternalName(),
+                ACC_FINAL | ACC_SUPER | visibilityFlag | getSyntheticAccessFlagForLambdaClass(classDescriptor),
-                      sw.makeJavaGenericSignature(),
+                asmType.getInternalName(),
-                      superClassAsmType.getInternalName(),
+                sw.makeJavaGenericSignature(),
-                      superInterfaceAsmTypes
+                superClassAsmType.getInternalName(),
+                superInterfaceAsmTypes
         );
 
         initDefaultSourceMappingIfNeeded(context, this, state);

compiler/backend/src/org/jetbrains/kotlin/codegen/PropertyReferenceCodegen.kt

@@ -92,7 +92,9 @@ class PropertyReferenceCodegen(
         v.defineClass(
             element,
             state.classFileVersion,
-            ACC_FINAL or ACC_SUPER or AsmUtil.getVisibilityAccessFlagForClass(classDescriptor),
+            ACC_FINAL or ACC_SUPER or
+                    AsmUtil.getVisibilityAccessFlagForClass(classDescriptor) or
+                    AsmUtil.getSyntheticAccessFlagForLambdaClass(classDescriptor),
             asmType.internalName,
             null,
             superAsmType.internalName,

compiler/testData/codegen/box/callableReference/classesAreSynthetic.kt

@@ -0,0 +1,20 @@
+// TARGET_BACKEND: JVM
+// IGNORE_BACKEND: JVM_IR
+// WITH_RUNTIME
+
+class C {
+    fun f() {}
+    val r = 0
+}
+
+fun check(c: Class<*>) {
+    if (!c.isSynthetic) throw AssertionError("Fail: $c is not synthetic: ${c.modifiers}")
+}
+
+fun box(): String {
+    check(C::f.javaClass)
+    check(C::r.javaClass)
+    check(C()::f.javaClass)
+    check(C()::r.javaClass)
+    return "OK"
+}

compiler/testData/codegen/bytecodeListing/noReceiverInCallableReferenceClasses.txt

@@ -7,7 +7,7 @@ public final class A {
 }
 
 @kotlin.Metadata
-final class NoReceiverInCallableReferenceClassesKt$A_bar$1 {
+synthetic final class NoReceiverInCallableReferenceClassesKt$A_bar$1 {
     public final static field INSTANCE: kotlin.reflect.KProperty1
     static method <clinit>(): void
     method <init>(): void
@@ -18,7 +18,7 @@ final class NoReceiverInCallableReferenceClassesKt$A_bar$1 {
 }
 
 @kotlin.Metadata
-final class NoReceiverInCallableReferenceClassesKt$A_foo$1 {
+synthetic final class NoReceiverInCallableReferenceClassesKt$A_foo$1 {
     public final static field INSTANCE: NoReceiverInCallableReferenceClassesKt$A_foo$1
     inner class NoReceiverInCallableReferenceClassesKt$A_foo$1
     static method <clinit>(): void
@@ -31,7 +31,7 @@ final class NoReceiverInCallableReferenceClassesKt$A_foo$1 {
 }
 
 @kotlin.Metadata
-final class NoReceiverInCallableReferenceClassesKt$aBar$1 {
+synthetic final class NoReceiverInCallableReferenceClassesKt$aBar$1 {
     method <init>(p0: A): void
     public @org.jetbrains.annotations.Nullable method get(): java.lang.Object
     public method getName(): java.lang.String
@@ -40,7 +40,7 @@ final class NoReceiverInCallableReferenceClassesKt$aBar$1 {
 }
 
 @kotlin.Metadata
-final class NoReceiverInCallableReferenceClassesKt$aFoo$1 {
+synthetic final class NoReceiverInCallableReferenceClassesKt$aFoo$1 {
     inner class NoReceiverInCallableReferenceClassesKt$aFoo$1
     method <init>(p0: A): void
     public final method getName(): java.lang.String

compiler/testData/writeFlags/callableReference/visibility/functionReference.kt

@@ -6,4 +6,4 @@ class A {
 
 // TESTED_OBJECT_KIND: class
 // TESTED_OBJECTS: A$bar$1
-// FLAGS: ACC_FINAL, ACC_SUPER
+// FLAGS: ACC_FINAL, ACC_SUPER, ACC_SYNTHETIC

compiler/testData/writeFlags/callableReference/visibility/functionReferenceInInlineFunction.kt

@@ -6,4 +6,4 @@ class A {
 
 // TESTED_OBJECT_KIND: class
 // TESTED_OBJECTS: A$bar$1
-// FLAGS: ACC_FINAL, ACC_PUBLIC, ACC_SUPER
+// FLAGS: ACC_FINAL, ACC_PUBLIC, ACC_SUPER, ACC_SYNTHETIC

compiler/testData/writeFlags/callableReference/visibility/propertyReference.kt

@@ -6,4 +6,4 @@ class A {
 
 // TESTED_OBJECT_KIND: class
 // TESTED_OBJECTS: A$bar$1
-// FLAGS: ACC_FINAL, ACC_SUPER
+// FLAGS: ACC_FINAL, ACC_SUPER, ACC_SYNTHETIC

compiler/testData/writeFlags/callableReference/visibility/propertyReferenceInInlineFunction.kt

@@ -6,4 +6,4 @@ class A {
 
 // TESTED_OBJECT_KIND: class
 // TESTED_OBJECTS: A$bar$1
-// FLAGS: ACC_FINAL, ACC_PUBLIC, ACC_SUPER
+// FLAGS: ACC_FINAL, ACC_PUBLIC, ACC_SUPER, ACC_SYNTHETIC

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

@@ -1744,6 +1744,11 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/box/callableReference"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.JVM, true);
         }
 
+        @TestMetadata("classesAreSynthetic.kt")
+        public void testClassesAreSynthetic() throws Exception {
+            runTest("compiler/testData/codegen/box/callableReference/classesAreSynthetic.kt");
+        }
+
         @TestMetadata("compiler/testData/codegen/box/callableReference/bound")
         @TestDataPath("$PROJECT_ROOT")
         @RunWith(JUnit3RunnerWithInners.class)

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

@@ -1744,6 +1744,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/box/callableReference"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.JVM, true);
         }
 
+        @TestMetadata("classesAreSynthetic.kt")
+        public void testClassesAreSynthetic() throws Exception {
+            runTest("compiler/testData/codegen/box/callableReference/classesAreSynthetic.kt");
+        }
+
         @TestMetadata("compiler/testData/codegen/box/callableReference/bound")
         @TestDataPath("$PROJECT_ROOT")
         @RunWith(JUnit3RunnerWithInners.class)

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

@@ -1744,6 +1744,11 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/box/callableReference"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.JVM_IR, true);
         }
 
+        @TestMetadata("classesAreSynthetic.kt")
+        public void testClassesAreSynthetic() throws Exception {
+            runTest("compiler/testData/codegen/box/callableReference/classesAreSynthetic.kt");
+        }
+
         @TestMetadata("compiler/testData/codegen/box/callableReference/bound")
         @TestDataPath("$PROJECT_ROOT")
         @RunWith(JUnit3RunnerWithInners.class)

idea/idea-jvm/src/org/jetbrains/kotlin/idea/debugger/filter/KotlinSyntheticTypeComponentProvider.kt

@@ -33,6 +33,7 @@ class KotlinSyntheticTypeComponentProvider: SyntheticTypeComponentProvider {
         val typeName = containingType.name()
         if (!FqNameUnsafe.isValid(typeName)) return false
 
+        // TODO: this is most likely not necessary since KT-28453 is fixed, but still can be useful when debugging old compiled code
         if (containingType.isCallableReferenceSyntheticClass()) {
             return true
         }