Proper enhancement for SAM adapters

compiler/frontend.java/src/org/jetbrains/kotlin/load/java/components/signatureEnhancement.kt

@@ -47,30 +47,8 @@ fun <D : CallableMemberDescriptor> D.enhance(): D {
     val enhancedReturnType = parts { it.getReturnType()!!.toReturnTypePart() }.enhance()
 
     if (this is JavaMethodDescriptor) {
-        val enhancedFunction = JavaMethodDescriptor.createJavaMethod(
-                getContainingDeclaration()!!,
-                getAnnotations(),
-                getName(),
-                getSource()
-        )
-        enhancedFunction.initialize(
-                enhancedReceiverType,
-                getDispatchReceiverParameter(),
-                getTypeParameters(),
-                enhancedValueParameters,
-                enhancedReturnType,
-                getModality(),
-                getVisibility()
-        )
-        enhancedFunction.setHasStableParameterNames(hasStableParameterNames())
-        enhancedFunction.setHasSynthesizedParameterNames(hasSynthesizedParameterNames())
-
-        for (overridden in getOverriddenDescriptors()) {
-            enhancedFunction.addOverriddenDescriptor(overridden)
-        }
-
         @suppress("UNCHECKED_CAST")
-        return enhancedFunction as D
+        return this.enhance(enhancedReceiverType, enhancedValueParameters, enhancedReturnType) as D
     }
 
     return this

compiler/frontend.java/src/org/jetbrains/kotlin/load/java/sam/SamAdapterFunctionDescriptor.java

@@ -17,6 +17,10 @@
 package org.jetbrains.kotlin.load.java.sam;
 
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptor;
+import org.jetbrains.kotlin.descriptors.FunctionDescriptor;
+import org.jetbrains.kotlin.descriptors.SimpleFunctionDescriptor;
 import org.jetbrains.kotlin.load.java.descriptors.JavaMethodDescriptor;
 import org.jetbrains.kotlin.load.java.descriptors.SamAdapterDescriptor;
 
@@ -24,8 +28,17 @@ import org.jetbrains.kotlin.load.java.descriptors.SamAdapterDescriptor;
     private final JavaMethodDescriptor declaration;
 
     public SamAdapterFunctionDescriptor(@NotNull JavaMethodDescriptor declaration) {
-        super(declaration.getContainingDeclaration(), null, declaration.getAnnotations(),
-              declaration.getName(), Kind.SYNTHESIZED, declaration.getSource());
+        this(declaration.getContainingDeclaration(), null, Kind.SYNTHESIZED, declaration);
+    }
+
+    private SamAdapterFunctionDescriptor(
+            @NotNull DeclarationDescriptor containingDeclaration,
+            @Nullable SimpleFunctionDescriptor original,
+            @NotNull Kind kind,
+            @NotNull JavaMethodDescriptor declaration
+    ) {
+        super(containingDeclaration, original, declaration.getAnnotations(),
+              declaration.getName(), kind, declaration.getSource());
         this.declaration = declaration;
         setHasStableParameterNames(declaration.hasStableParameterNames());
         setHasSynthesizedParameterNames(declaration.hasSynthesizedParameterNames());
@@ -36,4 +49,14 @@ import org.jetbrains.kotlin.load.java.descriptors.SamAdapterDescriptor;
     public JavaMethodDescriptor getOriginForSam() {
         return declaration;
     }
+
+    @NotNull
+    @Override
+    protected JavaMethodDescriptor createSubstitutedCopy(
+            @NotNull DeclarationDescriptor newOwner,
+            @Nullable FunctionDescriptor original,
+            @NotNull Kind kind
+    ) {
+        return new SamAdapterFunctionDescriptor(newOwner, (SimpleFunctionDescriptor) original, kind, declaration);
+    }
 }

core/descriptor.loader.java/src/org/jetbrains/kotlin/load/java/descriptors/JavaMethodDescriptor.java

@@ -18,14 +18,13 @@ package org.jetbrains.kotlin.load.java.descriptors;
 
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
-import org.jetbrains.kotlin.descriptors.DeclarationDescriptor;
-import org.jetbrains.kotlin.descriptors.FunctionDescriptor;
-import org.jetbrains.kotlin.descriptors.SimpleFunctionDescriptor;
-import org.jetbrains.kotlin.descriptors.SourceElement;
+import org.jetbrains.kotlin.descriptors.*;
 import org.jetbrains.kotlin.descriptors.annotations.Annotations;
-import org.jetbrains.kotlin.descriptors.impl.FunctionDescriptorImpl;
 import org.jetbrains.kotlin.descriptors.impl.SimpleFunctionDescriptorImpl;
 import org.jetbrains.kotlin.name.Name;
+import org.jetbrains.kotlin.types.JetType;
+
+import java.util.List;
 
 public class JavaMethodDescriptor extends SimpleFunctionDescriptorImpl implements JavaCallableMemberDescriptor {
     private Boolean hasStableParameterNames = null;
@@ -74,7 +73,7 @@ public class JavaMethodDescriptor extends SimpleFunctionDescriptorImpl implement
 
     @NotNull
     @Override
-    protected FunctionDescriptorImpl createSubstitutedCopy(
+    protected JavaMethodDescriptor createSubstitutedCopy(
             @NotNull DeclarationDescriptor newOwner,
             @Nullable FunctionDescriptor original,
             @NotNull Kind kind
@@ -91,4 +90,27 @@ public class JavaMethodDescriptor extends SimpleFunctionDescriptorImpl implement
         result.setHasSynthesizedParameterNames(hasSynthesizedParameterNames());
         return result;
     }
+
+    @NotNull
+    public JavaMethodDescriptor enhance(
+            @Nullable JetType enhancedReceiverType,
+            @NotNull List<ValueParameterDescriptor> enhancedValueParameters,
+            @NotNull JetType enhancedReturnType
+    ) {
+        JavaMethodDescriptor enhancedMethod = createSubstitutedCopy(getContainingDeclaration(), getOriginal(), getKind());
+        enhancedMethod.initialize(
+                enhancedReceiverType,
+                getDispatchReceiverParameter(),
+                getTypeParameters(),
+                enhancedValueParameters,
+                enhancedReturnType,
+                getModality(),
+                getVisibility()
+        );
+        for (FunctionDescriptor overridden : getOverriddenDescriptors()) {
+            enhancedMethod.addOverriddenDescriptor(overridden);
+        }
+
+        return enhancedMethod;
+    }
 }