Report error when delegation method hides superttype override

#KT-12531 Fixed

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/Errors.java

@@ -234,6 +234,7 @@ public interface Errors {
     DiagnosticFactory0<KtSuperTypeEntry> SUPERTYPE_NOT_INITIALIZED = DiagnosticFactory0.create(ERROR);
 
     DiagnosticFactory0<KtTypeReference> DELEGATION_NOT_TO_INTERFACE = DiagnosticFactory0.create(ERROR);
+    DiagnosticFactory2<KtDeclaration, CallableMemberDescriptor, List<CallableMemberDescriptor>> DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE = DiagnosticFactory2.create(ERROR);
     DiagnosticFactory0<KtTypeReference> SUPERTYPE_NOT_A_CLASS_OR_INTERFACE = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<KtTypeReference> SUPERTYPE_IS_EXTENSION_FUNCTION_TYPE = DiagnosticFactory0.create(ERROR);
 

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/rendering/DefaultErrorMessages.java

@@ -368,6 +368,7 @@ public class DefaultErrorMessages {
 
         MAP.put(DELEGATION_IN_INTERFACE, "Interfaces cannot use delegation");
         MAP.put(DELEGATION_NOT_TO_INTERFACE, "Only interfaces can be delegated to");
+        MAP.put(DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE, "Delegated member ''{0}'' hides supertype override: {1}. Please specify proper override explicitly", COMPACT, commaSeparated(SHORT_NAMES_IN_TYPES));
         MAP.put(NO_CONSTRUCTOR, "This class does not have a constructor");
         MAP.put(RESOLUTION_TO_CLASSIFIER, "{2}", NAME, TO_STRING, STRING);
         MAP.put(NOT_A_CLASS, "Not a class");

compiler/frontend/src/org/jetbrains/kotlin/resolve/TargetPlatform.kt

@@ -73,7 +73,8 @@ private val DEFAULT_DECLARATION_CHECKERS = listOf(
         InfixModifierChecker(),
         SinceKotlinAnnotationValueChecker,
         ReifiedTypeParameterAnnotationChecker(),
-        DynamicReceiverChecker
+        DynamicReceiverChecker,
+        DelegationChecker()
 )
 
 private val DEFAULT_CALL_CHECKERS = listOf(

compiler/frontend/src/org/jetbrains/kotlin/resolve/checkers/DelegationChecker.kt

@@ -0,0 +1,121 @@
+/*
+ * Copyright 2010-2016 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.kotlin.resolve.checkers
+
+import org.jetbrains.kotlin.descriptors.CallableMemberDescriptor
+import org.jetbrains.kotlin.descriptors.ClassDescriptor
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+import org.jetbrains.kotlin.descriptors.Modality
+import org.jetbrains.kotlin.diagnostics.DiagnosticSink
+import org.jetbrains.kotlin.diagnostics.Errors.DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE
+import org.jetbrains.kotlin.incremental.components.NoLookupLocation
+import org.jetbrains.kotlin.psi.KtClassOrObject
+import org.jetbrains.kotlin.psi.KtDeclaration
+import org.jetbrains.kotlin.psi.KtDelegatedSuperTypeEntry
+import org.jetbrains.kotlin.resolve.BindingContext
+import org.jetbrains.kotlin.resolve.DescriptorUtils
+import org.jetbrains.kotlin.resolve.MemberComparator
+import org.jetbrains.kotlin.resolve.OverridingUtil
+import org.jetbrains.kotlin.utils.DFS
+import org.jetbrains.kotlin.utils.keysToMapExceptNulls
+
+class DelegationChecker : SimpleDeclarationChecker {
+    override fun check(
+            declaration: KtDeclaration,
+            descriptor: DeclarationDescriptor,
+            diagnosticHolder: DiagnosticSink,
+            bindingContext: BindingContext
+    ) {
+        if (descriptor !is ClassDescriptor) return
+        if (declaration !is KtClassOrObject) return
+
+        val delegationDescriptors = descriptor.defaultType.memberScope.getContributedDescriptors().
+                filterIsInstance<CallableMemberDescriptor>().filter { it.kind == CallableMemberDescriptor.Kind.DELEGATION }.sortedWith(MemberComparator.INSTANCE)
+
+        for (specifier in declaration.superTypeListEntries) {
+            if (specifier is KtDelegatedSuperTypeEntry) {
+                val superType = specifier.typeReference?.let { bindingContext.get(BindingContext.TYPE, it) } ?: continue
+                val superTypeDescriptor = superType.constructor.declarationDescriptor as? ClassDescriptor ?: continue
+
+                val delegates = getDelegates(delegationDescriptors, superTypeDescriptor)
+                delegates.forEach { (delegated, delegatedTo) ->
+                    checkDescriptor(declaration, delegated, delegatedTo, diagnosticHolder)
+                }
+            }
+        }
+    }
+
+    private fun checkDescriptor(
+            classDeclaration: KtDeclaration,
+            delegatedDescriptor: CallableMemberDescriptor,
+            delegatedToDescriptor: CallableMemberDescriptor,
+            diagnosticHolder: DiagnosticSink
+    ) {
+        val reachableFromDelegated = findAllReachableDeclarations(delegatedDescriptor)
+        reachableFromDelegated.remove(delegatedDescriptor.original)
+        val toRemove = linkedSetOf<CallableMemberDescriptor>()
+        for (declaration in reachableFromDelegated) {
+            val reachable = findAllReachableDeclarations(declaration.original)
+            reachable.remove(declaration)
+            toRemove.addAll(reachable)
+        }
+        reachableFromDelegated.removeAll(toRemove)
+        reachableFromDelegated.remove(DescriptorUtils.unwrapFakeOverride(delegatedToDescriptor).original)
+
+        val nonAbstractReachable = reachableFromDelegated.filter { it.modality != Modality.ABSTRACT }
+
+        if (nonAbstractReachable.isNotEmpty()) {
+            /*In case of MANY_IMPL_MEMBER_NOT_IMPLEMENTED error there could be several elements otherwise only one*/
+            diagnosticHolder.report(DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE.on(classDeclaration, delegatedDescriptor, nonAbstractReachable.toList()))
+        }
+    }
+
+    fun getDelegates(
+            delegatedMethods: Iterable<CallableMemberDescriptor>,
+            toInterface: ClassDescriptor
+    ): Map<CallableMemberDescriptor, CallableMemberDescriptor> {
+        return delegatedMethods
+                .keysToMapExceptNulls { delegatingMember ->
+                    val actualDelegates = DescriptorUtils.getAllOverriddenDescriptors(delegatingMember)
+                            .filter { it.containingDeclaration == toInterface }
+                            .map { overriddenDescriptor ->
+                                val scope = toInterface.defaultType.memberScope
+                                val name = overriddenDescriptor.name
+
+                                // this is the actual member of delegateExpressionType that we are delegating to
+                                (scope.getContributedFunctions(name, NoLookupLocation.WHEN_CHECK_OVERRIDES) +
+                                 scope.getContributedVariables(name, NoLookupLocation.WHEN_CHECK_OVERRIDES))
+                                        .firstOrNull { it == overriddenDescriptor || OverridingUtil.overrides(it, overriddenDescriptor) }
+                            }
+
+                    actualDelegates.firstOrNull() as? CallableMemberDescriptor
+                }
+    }
+}
+
+private fun findAllReachableDeclarations(memberDescriptor: CallableMemberDescriptor): MutableSet<CallableMemberDescriptor> {
+    val collector = object : DFS.NodeHandlerWithListResult<CallableMemberDescriptor, CallableMemberDescriptor>() {
+        override fun afterChildren(current: CallableMemberDescriptor) {
+            if (current.kind.isReal) {
+                result.add(current.original)
+            }
+        }
+    }
+
+    DFS.dfs(listOf(memberDescriptor), { it.overriddenDescriptors }, collector)
+    return java.util.HashSet(collector.result())
+}

compiler/testData/diagnostics/tests/delegation/clashes/finalMemberOverridden.kt

@@ -38,18 +38,18 @@ class CBarT<T> : IBarT<T> {
     override val bar: T get() = null!!
 }
 
-<!OVERRIDING_FINAL_MEMBER_BY_DELEGATION!>class Test1<!> : Final(), IFoo by CFoo()
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!><!OVERRIDING_FINAL_MEMBER_BY_DELEGATION!>class Test1<!> : Final(), IFoo by CFoo()<!>
 
-<!OVERRIDING_FINAL_MEMBER_BY_DELEGATION!>class Test2<!> : Final(), IBar by CBar()
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!><!OVERRIDING_FINAL_MEMBER_BY_DELEGATION!>class Test2<!> : Final(), IBar by CBar()<!>
 
-<!OVERRIDING_FINAL_MEMBER_BY_DELEGATION, VAR_OVERRIDDEN_BY_VAL_BY_DELEGATION!>class Test3<!> : Final(), IQux by CQux()
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!><!OVERRIDING_FINAL_MEMBER_BY_DELEGATION, VAR_OVERRIDDEN_BY_VAL_BY_DELEGATION!>class Test3<!> : Final(), IQux by CQux()<!>
 
-<!OVERRIDING_FINAL_MEMBER_BY_DELEGATION!>class Test4<!> : Derived(), IFoo by CFoo()
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!><!OVERRIDING_FINAL_MEMBER_BY_DELEGATION!>class Test4<!> : Derived(), IFoo by CFoo()<!>
 
-<!OVERRIDING_FINAL_MEMBER_BY_DELEGATION!>class Test5<!> : Derived(), IBar by CBar()
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!><!OVERRIDING_FINAL_MEMBER_BY_DELEGATION!>class Test5<!> : Derived(), IBar by CBar()<!>
 
-<!OVERRIDING_FINAL_MEMBER_BY_DELEGATION, VAR_OVERRIDDEN_BY_VAL_BY_DELEGATION!>class Test6<!> : Derived(), IQux by CQux()
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!><!OVERRIDING_FINAL_MEMBER_BY_DELEGATION, VAR_OVERRIDDEN_BY_VAL_BY_DELEGATION!>class Test6<!> : Derived(), IQux by CQux()<!>
 
-<!OVERRIDING_FINAL_MEMBER_BY_DELEGATION!>class Test7<!> : Final(), IBarT<Int> by CBarT<Int>()
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!><!OVERRIDING_FINAL_MEMBER_BY_DELEGATION!>class Test7<!> : Final(), IBarT<Int> by CBarT<Int>()<!>
 
-<!OVERRIDING_FINAL_MEMBER_BY_DELEGATION!>class Test8<!> : Final(), IBarT<Int> by <!TYPE_MISMATCH!>CBar()<!>
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!><!OVERRIDING_FINAL_MEMBER_BY_DELEGATION!>class Test8<!> : Final(), IBarT<Int> by <!TYPE_MISMATCH!>CBar()<!><!>

compiler/testData/diagnostics/tests/delegation/covariantOverrides/fromClass.kt

@@ -6,7 +6,7 @@ open class IDerived1 : IBase1 {
     override fun foo(): String = "1"
 }
 
-<!RETURN_TYPE_MISMATCH_BY_DELEGATION!>class Broken1<!>(val b: IBase1) : IBase1 by b, IDerived1()
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!><!RETURN_TYPE_MISMATCH_BY_DELEGATION!>class Broken1<!>(val b: IBase1) : IBase1 by b, IDerived1()<!>
 
 interface IBase2 {
     val foo: Any
@@ -16,4 +16,4 @@ open class IDerived2 : IBase2 {
     override val foo: String = "2"
 }
 
-<!PROPERTY_TYPE_MISMATCH_BY_DELEGATION!>class Broken2<!>(val b: IBase2) : IBase2 by b, IDerived2()
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!><!PROPERTY_TYPE_MISMATCH_BY_DELEGATION!>class Broken2<!>(val b: IBase2) : IBase2 by b, IDerived2()<!>

compiler/testData/diagnostics/tests/delegationBy/abstractOverride.kt

@@ -0,0 +1,18 @@
+public interface Base {
+    fun test() = "OK"
+}
+
+
+abstract class Impl : Base {
+    override abstract fun test(): String
+}
+
+class Delegate : Base
+
+
+fun box(): String {
+    object : Impl(), Base by Delegate() {
+    }
+
+    return "OK"
+}

compiler/testData/diagnostics/tests/delegationBy/abstractOverride.txt

@@ -0,0 +1,26 @@
+package
+
+public fun box(): kotlin.String
+
+public interface Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate : Base {
+    public constructor Delegate()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public abstract class Impl : Base {
+    public constructor Impl()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public abstract override /*1*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/delegationToSubType.kt

@@ -0,0 +1,19 @@
+public interface Base {
+    fun test() = "OK"
+}
+
+public interface Base2 : Base 
+
+class Delegate : Base2
+
+fun box(): String {
+    object : Base, Base2 by Delegate() {
+
+    }
+
+    object : Base2, Base by Delegate() {
+    
+    }
+
+    return "OK"
+}

compiler/testData/diagnostics/tests/delegationBy/delegationToSubType.txt

@@ -0,0 +1,25 @@
+package
+
+public fun box(): kotlin.String
+
+public interface Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface Base2 : Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate : Base2 {
+    public constructor Delegate()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/delegationToSubTypeProperty.kt

@@ -0,0 +1,20 @@
+public interface Base {
+    val test: String
+            get() = "OK"
+}
+
+public interface Base2 : Base 
+
+class Delegate : Base2
+
+fun box(): String {
+    object : Base, Base2 by Delegate() {
+
+    }
+
+    object : Base2, Base by Delegate() {
+    
+    }
+
+    return "OK"
+}

compiler/testData/diagnostics/tests/delegationBy/delegationToSubTypeProperty.txt

@@ -0,0 +1,25 @@
+package
+
+public fun box(): kotlin.String
+
+public interface Base {
+    public open val test: kotlin.String
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface Base2 : Base {
+    public open override /*1*/ /*fake_override*/ val test: kotlin.String
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate : Base2 {
+    public constructor Delegate()
+    public open override /*1*/ /*fake_override*/ val test: kotlin.String
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/delegationToSubTypeWithOverride.kt

@@ -0,0 +1,19 @@
+public interface Base {
+    fun test() = "OK"
+}
+
+public interface Base2 : Base {
+    override fun test() = "OK2"
+}
+
+class Delegate : Base2
+
+fun box(): String {
+    object : Base, Base2 by Delegate() {
+    }
+
+    <!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>object<!> : Base2, Base by Delegate() {
+    }
+
+    return "OK"
+}

compiler/testData/diagnostics/tests/delegationBy/delegationToSubTypeWithOverride.txt

@@ -0,0 +1,25 @@
+package
+
+public fun box(): kotlin.String
+
+public interface Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface Base2 : Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate : Base2 {
+    public constructor Delegate()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/delegationToSubTypeWithOverrideProperty.kt

@@ -0,0 +1,26 @@
+public interface Base {
+    var test: String
+        get() = "OK"
+        set(s: String) {
+        }
+}
+
+public interface Base2 : Base {
+    override var test: String
+            get() = "OK2"
+            set(value) {}
+}
+
+class Delegate : Base2 {
+
+}
+
+fun box(): String {
+    object : Base, Base2 by Delegate() {
+    }
+
+    <!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>object<!> : Base2, Base by Delegate() {
+    }
+
+    return "OK"
+}

compiler/testData/diagnostics/tests/delegationBy/delegationToSubTypeWithOverrideProperty.txt

@@ -0,0 +1,25 @@
+package
+
+public fun box(): kotlin.String
+
+public interface Base {
+    public open var test: kotlin.String
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface Base2 : Base {
+    public open override /*1*/ var test: kotlin.String
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate : Base2 {
+    public constructor Delegate()
+    public open override /*1*/ /*fake_override*/ var test: kotlin.String
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/diamond.kt

@@ -0,0 +1,43 @@
+public interface Base {
+    fun test() = "Base"
+}
+
+public interface Base2 : Base {
+    override fun test() = "Base2"
+}
+
+public interface Base3 : Base {
+    override fun test() = "Base3"
+}
+
+class Impl : Base
+
+class Impl2 : Base2
+
+class Impl3 : Base3
+
+class ImplAll : Base, Base2, Base3 {
+    override fun test(): String {
+        return super<Base2>.test()
+    }
+}
+
+fun box(): String {
+    <!MANY_IMPL_MEMBER_NOT_IMPLEMENTED, DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>object<!> : Base2, Base3, Base by Impl() {
+
+    }
+
+    <!MANY_IMPL_MEMBER_NOT_IMPLEMENTED, DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>object<!> : Base2 by Impl2(), Base3, Base {
+
+    }
+
+    <!MANY_IMPL_MEMBER_NOT_IMPLEMENTED, DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>object<!> : Base2, Base3 by Impl3(), Base {
+
+    }
+
+    <!MANY_IMPL_MEMBER_NOT_IMPLEMENTED, MANY_IMPL_MEMBER_NOT_IMPLEMENTED, MANY_IMPL_MEMBER_NOT_IMPLEMENTED, DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE, DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE, DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>object<!> : Base2 by Impl2(), Base3 by Impl3(), Base by Impl() {
+
+    }
+
+    return "OK"
+}

compiler/testData/diagnostics/tests/delegationBy/diamond.txt

@@ -0,0 +1,56 @@
+package
+
+public fun box(): kotlin.String
+
+public interface Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface Base2 : Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface Base3 : Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Impl : Base {
+    public constructor Impl()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Impl2 : Base2 {
+    public constructor Impl2()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Impl3 : Base3 {
+    public constructor Impl3()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class ImplAll : Base, Base2, Base3 {
+    public constructor ImplAll()
+    public open override /*3*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*3*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*3*/ fun test(): kotlin.String
+    public open override /*3*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/explicitOverride.kt

@@ -0,0 +1,18 @@
+public interface Base {
+    fun test() = "OK"
+}
+
+open class Base2 : Base {
+    override fun test() = "OK2"
+}
+
+class Delegate : Base
+
+fun box(): String {
+
+    object : Base2(), Base by Delegate() {
+        override fun test() = "OK"
+    }
+
+    return "OK"
+}

compiler/testData/diagnostics/tests/delegationBy/explicitOverride.txt

@@ -0,0 +1,26 @@
+package
+
+public fun box(): kotlin.String
+
+public interface Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public open class Base2 : Base {
+    public constructor Base2()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate : Base {
+    public constructor Delegate()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/generic.kt

@@ -0,0 +1,14 @@
+public interface Base<T> {
+    fun test(p: T) = "Base"
+}
+
+public interface Derived<Y> : Base<Y>
+
+class Delegate<Z> : Derived<Z>
+
+fun box(): String {
+    object :  Derived<String> by Delegate() {
+    }
+    return "OK"
+}
+

compiler/testData/diagnostics/tests/delegationBy/generic.txt

@@ -0,0 +1,25 @@
+package
+
+public fun box(): kotlin.String
+
+public interface Base</*0*/ T> {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open fun test(/*0*/ p: T): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate</*0*/ Z> : Derived<Z> {
+    public constructor Delegate</*0*/ Z>()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(/*0*/ p: Z): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface Derived</*0*/ Y> : Base<Y> {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(/*0*/ p: Y): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/sameDelegationInHierarchy.kt

@@ -0,0 +1,16 @@
+public interface Base {
+    fun test() = "Base"
+}
+
+class Delegate : Base {
+    override fun test() = "Base"
+}
+
+public open class MyClass : Base by Delegate()
+
+fun box(): String {
+    <!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>object<!> : MyClass(), Base by Delegate() {
+    }
+    return "OK"
+}
+

compiler/testData/diagnostics/tests/delegationBy/sameDelegationInHierarchy.txt

@@ -0,0 +1,26 @@
+package
+
+public fun box(): kotlin.String
+
+public interface Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate : Base {
+    public constructor Delegate()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public open class MyClass : Base {
+    public constructor MyClass()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*delegation*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/sameDelegationInHierarchy2.kt

@@ -0,0 +1,21 @@
+public interface Base {
+    fun test() = "Base"
+}
+
+public interface Derived : Base {
+    override fun test() = "Derived"
+}
+
+
+class Delegate : Derived {
+    override fun test() = "Delegate"
+}
+
+public open class MyClass : Base by Delegate()
+
+fun box(): String {
+    <!MANY_IMPL_MEMBER_NOT_IMPLEMENTED, DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>object<!> : MyClass(), Derived by Delegate() {
+    }
+    return "OK"
+}
+

compiler/testData/diagnostics/tests/delegationBy/sameDelegationInHierarchy2.txt

@@ -0,0 +1,33 @@
+package
+
+public fun box(): kotlin.String
+
+public interface Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate : Derived {
+    public constructor Delegate()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface Derived : Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public open class MyClass : Base {
+    public constructor MyClass()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*delegation*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/severalDelegates.kt

@@ -0,0 +1,27 @@
+interface Base1 {
+    fun test() = "OK"
+}
+
+interface Base2 {
+    fun test2() = "OK"
+}
+
+
+class Delegate1 : Base1
+
+class Delegate2 : Base2
+
+
+public abstract class MyClass : Base1, Base2 {
+    override fun test(): String {
+        return "Class"
+    }
+
+    override fun test2(): String {
+        return "Class"
+    }
+}
+
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE, DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!><!MANY_IMPL_MEMBER_NOT_IMPLEMENTED!>class A<!> : MyClass(), Base1 by Delegate1(), <!SUPERTYPE_APPEARS_TWICE!>Base1<!> by <!TYPE_MISMATCH!>Delegate2()<!> {
+
+}<!>

compiler/testData/diagnostics/tests/delegationBy/severalDelegates.txt

@@ -0,0 +1,49 @@
+package
+
+public final class A : MyClass, Base1, Base1 {
+    public constructor A()
+    public open override /*2*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*2*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*2*/ /*delegation*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun test2(): kotlin.String
+    public open override /*2*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface Base1 {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface Base2 {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open fun test2(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate1 : Base1 {
+    public constructor Delegate1()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate2 : Base2 {
+    public constructor Delegate2()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test2(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public abstract class MyClass : Base1, Base2 {
+    public constructor MyClass()
+    public open override /*2*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*2*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun test(): kotlin.String
+    public open override /*1*/ fun test2(): kotlin.String
+    public open override /*2*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/simple.kt

@@ -0,0 +1,19 @@
+public interface Base {
+    fun getValue(): String
+
+    fun test() = getValue()
+}
+
+class Delegate : Base {
+    override fun getValue() = "Delegate"
+}
+
+public abstract class MyClass : Base {
+    override fun test(): String {
+        return "Class"
+    }
+}
+
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>class A : MyClass(), Base by Delegate() {
+    override fun getValue() = "Delegate"
+}<!>

compiler/testData/diagnostics/tests/delegationBy/simple.txt

@@ -0,0 +1,36 @@
+package
+
+public final class A : MyClass, Base {
+    public constructor A()
+    public open override /*2*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*2*/ fun getValue(): kotlin.String
+    public open override /*2*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*2*/ /*delegation*/ fun test(): kotlin.String
+    public open override /*2*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public interface Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public abstract fun getValue(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate : Base {
+    public constructor Delegate()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ fun getValue(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public abstract class MyClass : Base {
+    public constructor MyClass()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public abstract override /*1*/ /*fake_override*/ fun getValue(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/simpleNoOverride.kt

@@ -0,0 +1,15 @@
+interface Base {
+    fun test() = "OK"
+}
+
+open class Base2 : Base
+
+class Delegate : Base
+
+fun box(): String {
+    object : Base2(), Base by Delegate() {
+
+    }
+
+    return "OK"
+}

compiler/testData/diagnostics/tests/delegationBy/simpleNoOverride.txt

@@ -0,0 +1,26 @@
+package
+
+public fun box(): kotlin.String
+
+public interface Base {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public open class Base2 : Base {
+    public constructor Base2()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class Delegate : Base {
+    public constructor Delegate()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun test(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegationBy/simpleProp.kt

@@ -0,0 +1,17 @@
+public interface Base {
+    val test: String
+        get() = "OK"
+}
+
+open class Delegate : Base {
+    override val test: String
+        get() = "OK"
+}
+
+fun box(): String {
+    <!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>object<!> : Delegate(), Base by Delegate() {
+
+    }
+
+    return "OK"
+}

compiler/testData/diagnostics/tests/delegationBy/simpleProp.txt

@@ -0,0 +1,18 @@
+package
+
+public fun box(): kotlin.String
+
+public interface Base {
+    public open val test: kotlin.String
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public open class Delegate : Base {
+    public constructor Delegate()
+    public open override /*1*/ val test: kotlin.String
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/duplicateJvmSignature/erasure/superTraitAndDelegationToTraitImpl.kt

@@ -10,4 +10,4 @@ interface B {
 
 class <!CONFLICTING_JVM_DECLARATIONS!>C(f: A<String>)<!>: A<String> by f, B
 
-class D(f: A<Int>): A<Int> by f, B
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>class D(f: A<Int>): A<Int> by f, B<!>

compiler/testData/diagnostics/tests/override/ObjectDelegationManyImpl.kt

@@ -10,4 +10,4 @@ object Impl : D, E {
     override fun foo() {}
 }
 
-val obj: D = <!MANY_IMPL_MEMBER_NOT_IMPLEMENTED!>object<!> : D by Impl, E by Impl {}
+val obj: D = <!MANY_IMPL_MEMBER_NOT_IMPLEMENTED, DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>object<!> : D by Impl, E by Impl {}

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

@@ -6209,6 +6209,99 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
             }
         }
 
+        @TestMetadata("compiler/testData/diagnostics/tests/delegationBy")
+        @TestDataPath("$PROJECT_ROOT")
+        @RunWith(JUnit3RunnerWithInners.class)
+        public static class DelegationBy extends AbstractDiagnosticsTest {
+            @TestMetadata("abstractOverride.kt")
+            public void testAbstractOverride() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/abstractOverride.kt");
+                doTest(fileName);
+            }
+
+            public void testAllFilesPresentInDelegationBy() throws Exception {
+                KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/diagnostics/tests/delegationBy"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.ANY, true);
+            }
+
+            @TestMetadata("delegationToSubType.kt")
+            public void testDelegationToSubType() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/delegationToSubType.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("delegationToSubTypeProperty.kt")
+            public void testDelegationToSubTypeProperty() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/delegationToSubTypeProperty.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("delegationToSubTypeWithOverride.kt")
+            public void testDelegationToSubTypeWithOverride() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/delegationToSubTypeWithOverride.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("delegationToSubTypeWithOverrideProperty.kt")
+            public void testDelegationToSubTypeWithOverrideProperty() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/delegationToSubTypeWithOverrideProperty.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("diamond.kt")
+            public void testDiamond() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/diamond.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("explicitOverride.kt")
+            public void testExplicitOverride() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/explicitOverride.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("generic.kt")
+            public void testGeneric() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/generic.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("sameDelegationInHierarchy.kt")
+            public void testSameDelegationInHierarchy() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/sameDelegationInHierarchy.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("sameDelegationInHierarchy2.kt")
+            public void testSameDelegationInHierarchy2() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/sameDelegationInHierarchy2.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("severalDelegates.kt")
+            public void testSeveralDelegates() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/severalDelegates.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("simple.kt")
+            public void testSimple() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/simple.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("simpleNoOverride.kt")
+            public void testSimpleNoOverride() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/simpleNoOverride.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("simpleProp.kt")
+            public void testSimpleProp() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/delegationBy/simpleProp.kt");
+                doTest(fileName);
+            }
+        }
+
         @TestMetadata("compiler/testData/diagnostics/tests/deparenthesize")
         @TestDataPath("$PROJECT_ROOT")
         @RunWith(JUnit3RunnerWithInners.class)

idea/testData/quickfix/abstract/manyImpl.kt

@@ -1,5 +1,6 @@
 // "Make 'A' abstract" "false"
 // ERROR: Class 'X' must override public open fun foo(): Unit defined in X because it inherits many implementations of it
+// ERROR: Delegated member 'fun foo(): Unit' hides supertype override: public open fun foo(): Unit defined in E. Please specify proper override explicitly
 // ACTION: Create test
 // ACTION: Make internal
 // ACTION: Make private