Load Java enums as final classes

In case Java enum has an abstract member, it has the ACC_ABSTRACT flag
set in the bytecode. However, we should still load it with final
modality to be consistent with Kotlin enums which are always considered
final

 #KT-23426 Fixed

compiler/fir/resolve/tests/org/jetbrains/kotlin/fir/FirDiagnosticsSmokeTestGenerated.java

@@ -13439,6 +13439,11 @@ public class FirDiagnosticsSmokeTestGenerated extends AbstractFirDiagnosticsSmok
                 runTest("compiler/testData/diagnostics/tests/multiplatform/enum/enumEntryWithBody.kt");
             }
 
+            @TestMetadata("javaEnum.kt")
+            public void testJavaEnum() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/multiplatform/enum/javaEnum.kt");
+            }
+
             @TestMetadata("simpleEnum.kt")
             public void testSimpleEnum() throws Exception {
                 runTest("compiler/testData/diagnostics/tests/multiplatform/enum/simpleEnum.kt");

compiler/testData/compileKotlinAgainstJava/AbstractEnum.txt

@@ -2,7 +2,7 @@ package test
 
 public fun useEnum(): kotlin.String!
 
-public abstract enum class AbstractEnum : kotlin.Enum<test.AbstractEnum!> {
+public final enum class AbstractEnum : kotlin.Enum<test.AbstractEnum!> {
     enum entry ONE
 
     private constructor AbstractEnum()

compiler/testData/diagnostics/tests/enum/javaEnumWithAbstractFun.txt

@@ -2,7 +2,7 @@ package
 
 public fun main(): kotlin.Unit
 
-public abstract enum class A : kotlin.Enum<A!> {
+public final enum class A : kotlin.Enum<A!> {
     enum entry ENTRY
 
     public constructor A()

compiler/testData/diagnostics/tests/multiplatform/enum/javaEnum.kt

@@ -0,0 +1,32 @@
+// !LANGUAGE: +MultiPlatformProjects
+// MODULE: m1-common
+// FILE: common.kt
+expect enum class Foo {
+    ENTRY
+}
+
+expect enum class _TimeUnit
+
+// MODULE: m2-jvm(m1-common)
+// FILE: jvm.kt
+actual typealias Foo = FooImpl
+
+actual typealias _TimeUnit = java.util.concurrent.TimeUnit
+
+// FILE: FooImpl.java
+public enum FooImpl {
+    ENTRY("OK") {
+        @Override
+        public String getResult() {
+            return value;
+        }
+    };
+
+    protected final String value;
+
+    public FooImpl(String value) {
+        this.value = value;
+    }
+
+    public abstract String getResult();
+}

compiler/testData/diagnostics/tests/multiplatform/enum/javaEnum.txt

@@ -0,0 +1,59 @@
+// -- Module: <m1-common> --
+package
+
+public final expect enum class Foo : kotlin.Enum<Foo> {
+    expect enum entry ENTRY
+
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: Foo): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): Foo
+    public final /*synthesized*/ fun values(): kotlin.Array<Foo>
+}
+
+public final expect enum class _TimeUnit : kotlin.Enum<_TimeUnit> {
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: _TimeUnit): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): _TimeUnit
+    public final /*synthesized*/ fun values(): kotlin.Array<_TimeUnit>
+}
+
+
+// -- Module: <m2-jvm> --
+package
+
+public final enum class FooImpl : kotlin.Enum<FooImpl!> {
+    enum entry ENTRY
+
+    public constructor FooImpl(/*0*/ value: kotlin.String!)
+    public final override /*1*/ /*fake_override*/ val name: kotlin.String
+    public final override /*1*/ /*fake_override*/ val ordinal: kotlin.Int
+    protected/*protected and package*/ final val value: kotlin.String!
+    protected final override /*1*/ /*fake_override*/ fun clone(): kotlin.Any
+    public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: FooImpl!): kotlin.Int
+    public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    protected/*protected and package*/ final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun finalize(): kotlin.Unit
+    public final override /*1*/ /*fake_override*/ /*isHiddenForResolutionEverywhereBesideSupercalls*/ fun getDeclaringClass(): java.lang.Class<FooImpl!>!
+    public abstract fun getResult(): kotlin.String!
+    public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+
+    // Static members
+    public final /*synthesized*/ fun valueOf(/*0*/ value: kotlin.String): FooImpl
+    public final /*synthesized*/ fun values(): kotlin.Array<FooImpl>
+}
+public actual typealias Foo = FooImpl
+public actual typealias _TimeUnit = java.util.concurrent.TimeUnit

compiler/testData/loadJava/compiledJava/annotations/EnumArgumentWithCustomToString.txt

@@ -4,7 +4,7 @@ public open class EnumArgumentWithCustomToString {
     public constructor EnumArgumentWithCustomToString()
     @test.EnumArgumentWithCustomToString.EnumAnno(value = E.CAKE) @test.EnumArgumentWithCustomToString.EnumArrayAnno(value = {E.CAKE, E.CAKE}) public/*package*/ open fun annotated(): kotlin.Unit
 
-    public open enum class E : kotlin.Enum<test.EnumArgumentWithCustomToString.E!> {
+    public final enum class E : kotlin.Enum<test.EnumArgumentWithCustomToString.E!> {
         enum entry CAKE
 
         private constructor E()

compiler/testData/loadJava/compiledJava/enum/EnumWithSpecializedEntry.txt

@@ -1,6 +1,6 @@
 package test
 
-public open enum class EnumWithSpecializedEntry : kotlin.Enum<test.EnumWithSpecializedEntry!> {
+public final enum class EnumWithSpecializedEntry : kotlin.Enum<test.EnumWithSpecializedEntry!> {
     enum entry E1
 
     enum entry E2

compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java

@@ -13446,6 +13446,11 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                     runTest("compiler/testData/diagnostics/tests/multiplatform/enum/enumEntryWithBody.kt");
                 }
 
+                @TestMetadata("javaEnum.kt")
+                public void testJavaEnum() throws Exception {
+                    runTest("compiler/testData/diagnostics/tests/multiplatform/enum/javaEnum.kt");
+                }
+
                 @TestMetadata("simpleEnum.kt")
                 public void testSimpleEnum() throws Exception {
                     runTest("compiler/testData/diagnostics/tests/multiplatform/enum/simpleEnum.kt");

compiler/tests/org/jetbrains/kotlin/checkers/javac/DiagnosticsUsingJavacTestGenerated.java

@@ -13441,6 +13441,11 @@ public class DiagnosticsUsingJavacTestGenerated extends AbstractDiagnosticsUsing
                     runTest("compiler/testData/diagnostics/tests/multiplatform/enum/enumEntryWithBody.kt");
                 }
 
+                @TestMetadata("javaEnum.kt")
+                public void testJavaEnum() throws Exception {
+                    runTest("compiler/testData/diagnostics/tests/multiplatform/enum/javaEnum.kt");
+                }
+
                 @TestMetadata("simpleEnum.kt")
                 public void testSimpleEnum() throws Exception {
                     runTest("compiler/testData/diagnostics/tests/multiplatform/enum/simpleEnum.kt");

core/descriptors.jvm/src/org/jetbrains/kotlin/load/java/lazy/descriptors/LazyJavaClassDescriptor.kt

@@ -72,7 +72,7 @@ class LazyJavaClassDescriptor(
     }
 
     private val modality =
-        if (jClass.isAnnotationType) Modality.FINAL
+        if (jClass.isAnnotationType || jClass.isEnum) Modality.FINAL
         else Modality.convertFromFlags(jClass.isAbstract || jClass.isInterface, !jClass.isFinal)
 
     private val visibility = jClass.visibility