Move DeclarationDescriptor.substitute to separate interface Substitutable

To get rid of pointless/confusing implementations in ModuleDescriptor,
PackageViewDescriptor, TypeParameterDescriptor and others.

Note that there are still implementations that do not make sense, for
example in those subclasses of VariableDescriptor which are not also
subclasses of CallableMemberDescriptor (e.g. ValueParameterDescriptor).
Those can be removed by making CallableMemberDescriptor (instead of
CallableDescriptor) inherit from Substitutable. However, that would
require more changes in the compiler because CallableDescriptor is used
rather often in places where in fact only CallableMemberDescriptor
instances can appear.

Explicit return types and casts are required in some places now because
there's no single non-trivial supertype for
ClassifierDescriptorWithTypeParameters and CallableDescriptor.
Previously it was DeclarationDescriptorWithVisibility, now it's both
that and Substitutable<...>

compiler/backend/src/org/jetbrains/kotlin/codegen/context/RootContext.java

@@ -23,7 +23,6 @@ import org.jetbrains.kotlin.descriptors.DeclarationDescriptor;
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptorVisitor;
 import org.jetbrains.kotlin.descriptors.annotations.Annotations;
 import org.jetbrains.kotlin.name.Name;
-import org.jetbrains.kotlin.types.TypeSubstitutor;
 
 public class RootContext extends CodegenContext<RootContext.FakeDescriptor> {
     private final GenerationState state;
@@ -56,11 +55,6 @@ public class RootContext extends CodegenContext<RootContext.FakeDescriptor> {
             throw new IllegalStateException();
         }
 
-        @Override
-        public DeclarationDescriptor substitute(@NotNull TypeSubstitutor substitutor) {
-            throw new IllegalStateException();
-        }
-
         @Override
         public <R, D> R accept(DeclarationDescriptorVisitor<R, D> visitor, D data) {
             throw new IllegalStateException();

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

@@ -91,7 +91,7 @@ class OverloadResolver(
 
         collectModulePackageMembersWithSameName(
                 packageMembersByName,
-                c.functions.values + c.declaredClasses.values + c.typeAliases.values,
+                (c.functions.values as Collection<DeclarationDescriptor>) + c.declaredClasses.values + c.typeAliases.values,
                 overloadFilter
         ) {
             scope, name ->

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/checkers/UnderscoreUsageChecker.kt

@@ -31,7 +31,7 @@ object UnderscoreUsageChecker : CallChecker {
     override fun check(resolvedCall: ResolvedCall<*>, reportOn: PsiElement, context: CallCheckerContext) {
         if (resolvedCall is VariableAsFunctionResolvedCall) return
         val descriptor = resolvedCall.resultingDescriptor
-        val namedDescriptor = if (descriptor is ConstructorDescriptor) descriptor.containingDeclaration else descriptor
+        val namedDescriptor: DeclarationDescriptor = (descriptor as? ConstructorDescriptor)?.containingDeclaration ?: descriptor
         if (!namedDescriptor.name.asString().isUnderscoreOnlyName()) return
         checkCallElement(resolvedCall.call.callElement, context)
     }

compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/FileScopeFactory.kt

@@ -38,7 +38,6 @@ import org.jetbrains.kotlin.resolve.source.KotlinSourceElement
 import org.jetbrains.kotlin.script.getScriptExternalDependencies
 import org.jetbrains.kotlin.storage.StorageManager
 import org.jetbrains.kotlin.storage.getValue
-import org.jetbrains.kotlin.types.TypeSubstitutor
 import org.jetbrains.kotlin.utils.Printer
 
 data class FileScopes(val lexicalScope: LexicalScope, val importingScope: ImportingScope, val importResolver: ImportResolver)
@@ -236,7 +235,6 @@ class FileScopeFactory(
 
         override fun getOriginal() = this
         override val annotations: Annotations get() = Annotations.EMPTY
-        override fun substitute(substitutor: TypeSubstitutor) = this
 
         override fun <R : Any?, D : Any?> accept(visitor: DeclarationDescriptorVisitor<R, D>?, data: D): R {
             throw UnsupportedOperationException()

compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyAnnotations.kt

@@ -30,7 +30,6 @@ import org.jetbrains.kotlin.resolve.lazy.LazyEntity
 import org.jetbrains.kotlin.resolve.scopes.LexicalScope
 import org.jetbrains.kotlin.resolve.source.toSourceElement
 import org.jetbrains.kotlin.storage.StorageManager
-import org.jetbrains.kotlin.types.TypeSubstitutor
 
 abstract class LazyAnnotationsContext(
         val annotationResolver: AnnotationResolver,
@@ -172,7 +171,6 @@ class LazyAnnotationDescriptor(
         override fun getName() = Name.special("< file descriptor for annotation resolution >")
 
         private fun error(): Nothing = error("This method should not be called")
-        override fun substitute(substitutor: TypeSubstitutor): DeclarationDescriptor? = error()
         override fun <R : Any?, D : Any?> accept(visitor: DeclarationDescriptorVisitor<R, D>?, data: D): R = error()
         override fun acceptVoid(visitor: DeclarationDescriptorVisitor<Void, Void>?) = error()
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/descriptors/IrBuiltinsPackageFragmentDescriptor.kt

@@ -21,7 +21,6 @@ import org.jetbrains.kotlin.descriptors.annotations.Annotations
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.resolve.scopes.MemberScope
-import org.jetbrains.kotlin.types.TypeSubstitutor
 
 interface IrBuiltinsPackageFragmentDescriptor : PackageFragmentDescriptor
 
@@ -40,7 +39,6 @@ class IrBuiltinsPackageFragmentDescriptorImpl(
     override fun getOriginal(): DeclarationDescriptorWithSource = this
     override fun getSource(): SourceElement = SourceElement.NO_SOURCE
     override val annotations: Annotations = Annotations.EMPTY
-    override fun substitute(substitutor: TypeSubstitutor): DeclarationDescriptor = throw UnsupportedOperationException()
 
     override fun <R : Any?, D : Any?> accept(visitor: DeclarationDescriptorVisitor<R, D>, data: D): R {
         return visitor.visitPackageFragmentDescriptor(this, data)
@@ -50,5 +48,3 @@ class IrBuiltinsPackageFragmentDescriptorImpl(
         visitor.visitPackageFragmentDescriptor(this, null)
     }
 }
-
-

compiler/tests-common/org/jetbrains/kotlin/jvm/runtime/AbstractJvmRuntimeDescriptorLoaderTest.kt

@@ -45,7 +45,6 @@ import org.jetbrains.kotlin.test.KotlinTestUtils.TestFileFactoryNoModules
 import org.jetbrains.kotlin.test.util.DescriptorValidator.ValidationVisitor.errorTypesForbidden
 import org.jetbrains.kotlin.test.util.RecursiveDescriptorComparator
 import org.jetbrains.kotlin.test.util.RecursiveDescriptorComparator.Configuration
-import org.jetbrains.kotlin.types.TypeSubstitutor
 import org.jetbrains.kotlin.utils.Printer
 import org.jetbrains.kotlin.utils.sure
 import java.io.File
@@ -221,7 +220,6 @@ abstract class AbstractJvmRuntimeDescriptorLoaderTest : TestCaseWithTmpdir() {
 
         override fun getContainingDeclaration() = null
         override fun getOriginal() = throw UnsupportedOperationException()
-        override fun substitute(substitutor: TypeSubstitutor) = throw UnsupportedOperationException()
         override fun acceptVoid(visitor: DeclarationDescriptorVisitor<Void, Void>?) = throw UnsupportedOperationException()
         override fun getName() = throw UnsupportedOperationException()
         override val annotations: Annotations

core/descriptors/src/org/jetbrains/kotlin/descriptors/CallableDescriptor.java

@@ -20,12 +20,12 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.annotations.ReadOnly;
 import org.jetbrains.kotlin.types.KotlinType;
-import org.jetbrains.kotlin.types.TypeSubstitutor;
 
 import java.util.Collection;
 import java.util.List;
 
-public interface CallableDescriptor extends DeclarationDescriptorWithVisibility, DeclarationDescriptorNonRoot {
+public interface CallableDescriptor extends DeclarationDescriptorWithVisibility, DeclarationDescriptorNonRoot,
+                                            Substitutable<CallableDescriptor> {
     @Nullable
     ReceiverParameterDescriptor getExtensionReceiverParameter();
 
@@ -46,9 +46,6 @@ public interface CallableDescriptor extends DeclarationDescriptorWithVisibility,
     @Override
     CallableDescriptor getOriginal();
 
-    @Override
-    CallableDescriptor substitute(@NotNull TypeSubstitutor substitutor);
-
     @NotNull
     List<ValueParameterDescriptor> getValueParameters();
 

core/descriptors/src/org/jetbrains/kotlin/descriptors/ClassDescriptor.java

@@ -23,7 +23,6 @@ import org.jetbrains.kotlin.resolve.scopes.MemberScope;
 import org.jetbrains.kotlin.types.SimpleType;
 import org.jetbrains.kotlin.types.TypeProjection;
 import org.jetbrains.kotlin.types.TypeSubstitution;
-import org.jetbrains.kotlin.types.TypeSubstitutor;
 
 import java.util.Collection;
 import java.util.List;
@@ -59,10 +58,6 @@ public interface ClassDescriptor extends ClassifierDescriptorWithTypeParameters,
     @Override
     SimpleType getDefaultType();
 
-    @NotNull
-    @Override
-    ClassDescriptor substitute(@NotNull TypeSubstitutor substitutor);
-
     /**
      * @return nested object declared as 'companion' if one is present.
      */

core/descriptors/src/org/jetbrains/kotlin/descriptors/ClassifierDescriptorWithTypeParameters.java

@@ -22,7 +22,8 @@ import org.jetbrains.annotations.ReadOnly;
 import java.util.List;
 
 public interface ClassifierDescriptorWithTypeParameters
-        extends ClassifierDescriptor, DeclarationDescriptorWithVisibility, MemberDescriptor {
+        extends ClassifierDescriptor, DeclarationDescriptorWithVisibility, MemberDescriptor,
+                Substitutable<ClassifierDescriptorWithTypeParameters> {
     /**
      * @return <code>true</code> if this class contains a reference to its outer class (as opposed to static nested class)
      */

core/descriptors/src/org/jetbrains/kotlin/descriptors/DeclarationDescriptor.java

@@ -19,7 +19,6 @@ package org.jetbrains.kotlin.descriptors;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.kotlin.descriptors.annotations.Annotated;
-import org.jetbrains.kotlin.types.TypeSubstitutor;
 
 public interface DeclarationDescriptor extends Annotated, Named {
     /**
@@ -34,9 +33,6 @@ public interface DeclarationDescriptor extends Annotated, Named {
     @Nullable
     DeclarationDescriptor getContainingDeclaration();
 
-    @Nullable
-    DeclarationDescriptor substitute(@NotNull TypeSubstitutor substitutor);
-
     <R, D> R accept(DeclarationDescriptorVisitor<R, D> visitor, D data);
 
     void acceptVoid(DeclarationDescriptorVisitor<Void, Void> visitor);

core/descriptors/src/org/jetbrains/kotlin/descriptors/ModuleDescriptor.kt

@@ -19,7 +19,6 @@ package org.jetbrains.kotlin.descriptors
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
-import org.jetbrains.kotlin.types.TypeSubstitutor
 
 interface ModuleDescriptor : DeclarationDescriptor {
     override fun getContainingDeclaration(): DeclarationDescriptor? = null
@@ -28,10 +27,6 @@ interface ModuleDescriptor : DeclarationDescriptor {
 
     fun shouldSeeInternalsOf(targetModule: ModuleDescriptor): Boolean
 
-    override fun substitute(substitutor: TypeSubstitutor): ModuleDescriptor {
-        return this
-    }
-
     override fun <R, D> accept(visitor: DeclarationDescriptorVisitor<R, D>, data: D): R {
         return visitor.visitModuleDeclaration(this, data)
     }

core/descriptors/src/org/jetbrains/kotlin/descriptors/Substitutable.kt

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2010-2017 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.descriptors
+
+import org.jetbrains.kotlin.types.TypeSubstitutor
+
+interface Substitutable<out T : DeclarationDescriptorNonRoot> {
+    fun substitute(substitutor: TypeSubstitutor): T
+}

core/descriptors/src/org/jetbrains/kotlin/descriptors/TypeAliasDescriptor.kt

@@ -18,7 +18,6 @@ package org.jetbrains.kotlin.descriptors
 
 import org.jetbrains.kotlin.descriptors.impl.TypeAliasConstructorDescriptor
 import org.jetbrains.kotlin.types.SimpleType
-import org.jetbrains.kotlin.types.TypeSubstitutor
 
 interface TypeAliasDescriptor : ClassifierDescriptorWithTypeParameters {
     /// Right-hand side of the type alias definition.
@@ -33,7 +32,5 @@ interface TypeAliasDescriptor : ClassifierDescriptorWithTypeParameters {
 
     override fun getOriginal(): TypeAliasDescriptor
 
-    override fun substitute(substitutor: TypeSubstitutor): TypeAliasDescriptor
-
     val constructors: Collection<TypeAliasConstructorDescriptor>
 }

core/descriptors/src/org/jetbrains/kotlin/descriptors/TypeParameterDescriptor.java

@@ -19,7 +19,6 @@ package org.jetbrains.kotlin.descriptors;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.kotlin.types.KotlinType;
 import org.jetbrains.kotlin.types.TypeConstructor;
-import org.jetbrains.kotlin.types.TypeSubstitutor;
 import org.jetbrains.kotlin.types.Variance;
 
 import java.util.List;
@@ -37,11 +36,6 @@ public interface TypeParameterDescriptor extends ClassifierDescriptor {
     @Override
     TypeConstructor getTypeConstructor();
 
-    @NotNull
-    @Override
-    @Deprecated // Use the static method DescriptorSubstitutor.substituteTypeParameters()
-    TypeParameterDescriptor substitute(@NotNull TypeSubstitutor substitutor);
-
     @NotNull
     @Override
     TypeParameterDescriptor getOriginal();

core/descriptors/src/org/jetbrains/kotlin/descriptors/impl/AbstractTypeParameterDescriptor.java

@@ -134,13 +134,6 @@ public abstract class AbstractTypeParameterDescriptor extends DeclarationDescrip
         return (TypeParameterDescriptor) super.getOriginal();
     }
 
-    @NotNull
-    @Override
-    @Deprecated
-    public TypeParameterDescriptor substitute(@NotNull TypeSubstitutor substitutor) {
-        throw new UnsupportedOperationException("Don't call substitute() on type parameters");
-    }
-
     @Override
     public <R, D> R accept(DeclarationDescriptorVisitor<R, D> visitor, D data) {
         return visitor.visitTypeParameterDescriptor(this, data);

core/descriptors/src/org/jetbrains/kotlin/descriptors/impl/LazyPackageViewDescriptorImpl.kt

@@ -16,7 +16,6 @@
 
 package org.jetbrains.kotlin.descriptors.impl
 
-import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptorVisitor
 import org.jetbrains.kotlin.descriptors.PackageFragmentDescriptor
 import org.jetbrains.kotlin.descriptors.PackageViewDescriptor
@@ -27,7 +26,6 @@ import org.jetbrains.kotlin.resolve.scopes.LazyScopeAdapter
 import org.jetbrains.kotlin.resolve.scopes.MemberScope
 import org.jetbrains.kotlin.storage.StorageManager
 import org.jetbrains.kotlin.storage.getValue
-import org.jetbrains.kotlin.types.TypeSubstitutor
 
 class LazyPackageViewDescriptorImpl(
         override val module: ModuleDescriptorImpl,
@@ -65,7 +63,5 @@ class LazyPackageViewDescriptorImpl(
         return result
     }
 
-    override fun substitute(substitutor: TypeSubstitutor): DeclarationDescriptor? = this
-
     override fun <R, D> accept(visitor: DeclarationDescriptorVisitor<R, D>, data: D): R = visitor.visitPackageViewDescriptor(this, data)
 }

core/descriptors/src/org/jetbrains/kotlin/descriptors/impl/PackageFragmentDescriptorImpl.kt

@@ -16,18 +16,18 @@
 
 package org.jetbrains.kotlin.descriptors.impl
 
-import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptorVisitor
+import org.jetbrains.kotlin.descriptors.ModuleDescriptor
+import org.jetbrains.kotlin.descriptors.PackageFragmentDescriptor
+import org.jetbrains.kotlin.descriptors.SourceElement
 import org.jetbrains.kotlin.descriptors.annotations.Annotations
 import org.jetbrains.kotlin.name.FqName
-import org.jetbrains.kotlin.types.TypeSubstitutor
 
 abstract class PackageFragmentDescriptorImpl(
         module: ModuleDescriptor,
         final override val fqName: FqName
 ) : DeclarationDescriptorNonRootImpl(module, Annotations.EMPTY, fqName.shortNameOrSpecial(), SourceElement.NO_SOURCE),
         PackageFragmentDescriptor {
-    override fun substitute(substitutor: TypeSubstitutor): DeclarationDescriptor? = this
-
     override fun <R, D> accept(visitor: DeclarationDescriptorVisitor<R, D>, data: D): R =
             visitor.visitPackageFragmentDescriptor(this, data)
 

core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/SubstitutingScope.kt

@@ -17,6 +17,7 @@
 package org.jetbrains.kotlin.resolve.scopes
 
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+import org.jetbrains.kotlin.descriptors.Substitutable
 import org.jetbrains.kotlin.incremental.components.LookupLocation
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.resolve.calls.inference.wrapWithCapturingSubstitution
@@ -41,12 +42,15 @@ class SubstitutingScope(private val workerScope: MemberScope, givenSubstitutor:
             substitutedDescriptors = HashMap<DeclarationDescriptor, DeclarationDescriptor>()
         }
 
-        val substituted = substitutedDescriptors!!.getOrPut(descriptor, {
+        val substituted = substitutedDescriptors!!.getOrPut(descriptor) {
-            descriptor.substitute(substitutor).sure {
+            when (descriptor) {
-                "We expect that no conflict should happen while substitution is guaranteed to generate invariant projection, " +
+                is Substitutable<*> -> descriptor.substitute(substitutor).sure {
-                "but $descriptor substitution fails"
+                    "We expect that no conflict should happen while substitution is guaranteed to generate invariant projection, " +
+                    "but $descriptor substitution fails"
+                }
+                else -> error("Unknown descriptor in scope: $descriptor")
             }
-        })
+        }
 
         @Suppress("UNCHECKED_CAST")
         return substituted as D

core/descriptors/src/org/jetbrains/kotlin/types/ErrorUtils.java

@@ -99,13 +99,6 @@ public class ErrorUtils {
 
             @Override
             public void acceptVoid(DeclarationDescriptorVisitor<Void, Void> visitor) {
-
-            }
-
-            @NotNull
-            @Override
-            public ModuleDescriptor substitute(@NotNull TypeSubstitutor substitutor) {
-                return this;
             }
 
             @Override

idea/idea-analysis/src/org/jetbrains/kotlin/idea/decompiler/navigation/findDecompiledDeclaration.kt

@@ -104,11 +104,12 @@ private fun findCandidateDeclarationsInIndex(
         return KotlinFullClassNameIndex.getInstance().get(containingClass.fqNameSafe.asString(), project, scope)
     }
 
-    val topLevelDeclaration = DescriptorUtils.getParentOfType(referencedDescriptor, PropertyDescriptor::class.java, false)
+    val topLevelDeclaration =
-                              ?: DescriptorUtils.getParentOfType(referencedDescriptor, TypeAliasConstructorDescriptor::class.java, false)?.typeAliasDescriptor
+            DescriptorUtils.getParentOfType(referencedDescriptor, PropertyDescriptor::class.java, false) as DeclarationDescriptor?
-                              ?: DescriptorUtils.getParentOfType(referencedDescriptor, FunctionDescriptor::class.java, false)
+            ?: DescriptorUtils.getParentOfType(referencedDescriptor, TypeAliasConstructorDescriptor::class.java, false)?.typeAliasDescriptor
-                              ?: DescriptorUtils.getParentOfType(referencedDescriptor, TypeAliasDescriptor::class.java, false)
+            ?: DescriptorUtils.getParentOfType(referencedDescriptor, FunctionDescriptor::class.java, false)
-                              ?: return emptyList()
+            ?: DescriptorUtils.getParentOfType(referencedDescriptor, TypeAliasDescriptor::class.java, false)
+            ?: return emptyList()
 
     // filter out synthetic descriptors
     if (!DescriptorUtils.isTopLevelDeclaration(topLevelDeclaration)) return emptyList()

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/smart/Utils.kt

@@ -208,11 +208,12 @@ fun<TDescriptor: DeclarationDescriptor?> MutableCollection<LookupElement>.addLoo
     }
 }
 
+@Suppress("UNCHECKED_CAST")
 private fun <T : DeclarationDescriptor?> T.substituteFixed(substitutor: TypeSubstitutor): T {
-    if (this is LocalVariableDescriptor || this is ValueParameterDescriptor || this is TypeParameterDescriptor) { // TODO: it's not implemented for them
+    if (this is LocalVariableDescriptor || this is ValueParameterDescriptor || this !is Substitutable<*>) {
         return this
     }
-    return this?.substitute(substitutor) as T
+    return this.substitute(substitutor) as T
 }
 
 private fun MutableCollection<LookupElement>.addLookupElementsForNullable(factory: () -> Collection<LookupElement>, matchedInfos: Collection<ExpectedInfo>) {

idea/src/org/jetbrains/kotlin/idea/highlighter/markers/DeclaredHeaderMarker.kt

@@ -47,7 +47,7 @@ private enum class SourceKind { NONE, PRODUCTION, TEST }
 
 fun ModuleDescriptor.hasDeclarationOf(descriptor: MemberDescriptor) = declarationOf(descriptor) != null
 
-private fun ModuleDescriptor.declarationOf(descriptor: MemberDescriptor) =
+private fun ModuleDescriptor.declarationOf(descriptor: MemberDescriptor): DeclarationDescriptor? =
         with (HeaderImplDeclarationChecker(this)) {
             when (descriptor) {
                 is CallableMemberDescriptor ->

idea/src/org/jetbrains/kotlin/idea/highlighter/markers/ImplementedHeaderMarker.kt

@@ -32,7 +32,7 @@ import java.awt.event.MouseEvent
 fun ModuleDescriptor.hasImplementationsOf(descriptor: MemberDescriptor) =
         implementationsOf(descriptor).isNotEmpty()
 
-private fun ModuleDescriptor.implementationsOf(descriptor: MemberDescriptor) =
+private fun ModuleDescriptor.implementationsOf(descriptor: MemberDescriptor): List<DeclarationDescriptor> =
         with (HeaderImplDeclarationChecker(this)) {
             when (descriptor) {
                 is CallableMemberDescriptor -> descriptor.findNamesakesFromTheSameModule().filter { it.isImpl }