Proper concrete implementation filtering in java 8 interface case

compiler/backend-common/src/org/jetbrains/kotlin/backend/common/bridges/bridges.kt

@@ -23,6 +23,12 @@ interface FunctionHandle {
     val isDeclaration: Boolean
     val isAbstract: Boolean
 
+    /** On finding concrete super declaration we should distinguish non-abstract java8/js default methods from
+    * class ones (see [findConcreteSuperDeclaration] method in bridges.kt).
+    * Note that interface methods with body compiled to jvm 8 target are assumed to be non-abstract in bridges method calculation
+    * (more details in [DescriptorBasedFunctionHandle.isBodyOwner] comment).*/
+    val isInterfaceDeclaration: Boolean
+
     fun getOverridden(): Iterable<FunctionHandle>
 }
 
@@ -108,7 +114,7 @@ fun <Function : FunctionHandle> findConcreteSuperDeclaration(function: Function)
     }
     result.removeAll(toRemove)
 
-    val concreteRelevantDeclarations = result.filter { !it.isAbstract }
+    val concreteRelevantDeclarations = result.filter { !it.isAbstract && !it.isInterfaceDeclaration }
     if (concreteRelevantDeclarations.size != 1) {
         error("Concrete fake override $function should have exactly one concrete super-declaration: $concreteRelevantDeclarations")
     }

compiler/backend-common/src/org/jetbrains/kotlin/backend/common/bridges/impl.kt

@@ -72,6 +72,9 @@ class DescriptorBasedFunctionHandle(
             descriptor.modality == Modality.ABSTRACT ||
             isBodyOwner(descriptor.containingDeclaration)
 
+    override val isInterfaceDeclaration: Boolean
+        get() = DescriptorUtils.isInterface(descriptor.containingDeclaration)
+
     override fun getOverridden() = overridden
 
     override fun hashCode(): Int {

compiler/testData/codegen/java8/box/jvm8/oneImplementation.kt

@@ -0,0 +1,19 @@
+// JVM_TARGET: 1.8
+interface KCallable {
+    val returnType: String
+}
+
+interface KCallableImpl : KCallable {
+    override val returnType: String
+        get() = "OK"
+}
+
+interface KCallableImpl2 : KCallableImpl
+
+open class DescriptorBasedProperty : KCallableImpl
+open class KProperty1Impl : DescriptorBasedProperty(), KCallableImpl2
+open class KMutableProperty1Impl : KProperty1Impl(), KCallable
+
+fun box(): String {
+    return KMutableProperty1Impl().returnType
+}

compiler/testData/codegen/java8/box/jvm8/oneImplementation2.kt

@@ -0,0 +1,24 @@
+// JVM_TARGET: 1.8
+interface KCallable {
+    val returnType: String
+}
+
+interface KCallableImpl : KCallable {
+    override val returnType: String
+        get() = "OK"
+}
+
+interface KProperty : KCallable
+interface KPropertyImpl : KProperty, KCallableImpl
+interface KMutableProperty : KProperty
+interface KProperty1 : KProperty
+interface KMutableProperty1 : KProperty1, KMutableProperty
+interface KMutablePropertyImpl : KPropertyImpl
+
+open class DescriptorBasedProperty : KCallableImpl
+open class KProperty1Impl : DescriptorBasedProperty(), KProperty1, KPropertyImpl
+open class KMutableProperty1Impl : KProperty1Impl(), KMutableProperty1, KMutablePropertyImpl
+
+fun box(): String {
+    return KMutableProperty1Impl().returnType
+}

compiler/tests-java8/tests/org/jetbrains/kotlin/codegen/BlackBoxWithJava8CodegenTestGenerated.java

@@ -145,6 +145,18 @@ public class BlackBoxWithJava8CodegenTestGenerated extends AbstractBlackBoxCodeg
             doTest(fileName);
         }
 
+        @TestMetadata("oneImplementation.kt")
+        public void testOneImplementation() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/java8/box/jvm8/oneImplementation.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("oneImplementation2.kt")
+        public void testOneImplementation2() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/java8/box/jvm8/oneImplementation2.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("simpleCall.kt")
         public void testSimpleCall() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/java8/box/jvm8/simpleCall.kt");

compiler/tests/org/jetbrains/kotlin/codegen/BridgeTest.kt

@@ -28,7 +28,7 @@ class BridgeTest : TestCase() {
     private class Fun(val text: String) : FunctionHandle {
         override val isDeclaration: Boolean get() = text[1] == 'D'
         override val isAbstract: Boolean get() = text[0] == '-'
-
+        override val isInterfaceDeclaration: Boolean get() = false
         val signature: Char get() = text[2]
 
         val overriddenFunctions: MutableList<Fun> = arrayListOf()