Create PropagatedMethodSignature nested class

Should be an abstraction over SignaturesPropagationData

compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/resolver/ExternalSignatureResolver.java

@@ -18,10 +18,7 @@ package org.jetbrains.jet.lang.resolve.java.resolver;
 
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
-import org.jetbrains.jet.lang.descriptors.CallableMemberDescriptor;
+import org.jetbrains.jet.lang.descriptors.*;
-import org.jetbrains.jet.lang.descriptors.ClassDescriptor;
-import org.jetbrains.jet.lang.descriptors.TypeParameterDescriptor;
-import org.jetbrains.jet.lang.descriptors.ValueParameterDescriptor;
 import org.jetbrains.jet.lang.resolve.BindingTrace;
 import org.jetbrains.jet.lang.resolve.java.JavaBindingContext;
 import org.jetbrains.jet.lang.resolve.java.kotlinSignature.AlternativeFieldSignatureData;
@@ -44,15 +41,15 @@ public class ExternalSignatureResolver {
     }
 
     private abstract static class MemberSignature {
-        private final String signatureError;
+        private final List<String> signatureErrors;
 
-        protected MemberSignature(@Nullable String signatureError) {
+        protected MemberSignature(@NotNull List<String> signatureErrors) {
-            this.signatureError = signatureError;
+            this.signatureErrors = signatureErrors;
         }
 
         @NotNull
         public List<String> getErrors() {
-            return signatureError == null ? Collections.<String>emptyList() : Collections.singletonList(signatureError);
+            return signatureErrors;
         }
     }
 
@@ -67,9 +64,9 @@ public class ExternalSignatureResolver {
                 @Nullable JetType receiverType,
                 @NotNull List<ValueParameterDescriptor> valueParameters,
                 @NotNull List<TypeParameterDescriptor> typeParameters,
-                @Nullable String signatureError
+                @NotNull List<String> signatureErrors
         ) {
-            super(signatureError);
+            super(signatureErrors);
             this.returnType = returnType;
             this.receiverType = receiverType;
             this.valueParameters = valueParameters;
@@ -101,7 +98,7 @@ public class ExternalSignatureResolver {
         private final JetType returnType;
 
         public AlternativeFieldSignature(@NotNull JetType returnType, @Nullable String signatureError) {
-            super(signatureError);
+            super(signatureError == null ? Collections.<String>emptyList() : Collections.singletonList(signatureError));
             this.returnType = returnType;
         }
 
@@ -111,8 +108,29 @@ public class ExternalSignatureResolver {
         }
     }
 
+    public static class PropagatedMethodSignature extends AlternativeMethodSignature {
+        private final List<FunctionDescriptor> superMethods;
+
+        public PropagatedMethodSignature(
+                @Nullable JetType returnType,
+                @Nullable JetType receiverType,
+                @NotNull List<ValueParameterDescriptor> valueParameters,
+                @NotNull List<TypeParameterDescriptor> typeParameters,
+                @NotNull List<String> signatureErrors,
+                @NotNull List<FunctionDescriptor> superMethods
+        ) {
+            super(returnType, receiverType, valueParameters, typeParameters, signatureErrors);
+            this.superMethods = superMethods;
+        }
+
+        @NotNull
+        public List<FunctionDescriptor> getSuperMethods() {
+            return superMethods;
+        }
+    }
+
     @NotNull
-    public SignaturesPropagationData resolvePropagatedSignature(
+    public PropagatedMethodSignature resolvePropagatedSignature(
             @NotNull JavaMethod method,
             @NotNull ClassDescriptor owner,
             @NotNull JetType returnType,
@@ -120,7 +138,11 @@ public class ExternalSignatureResolver {
             @NotNull List<ValueParameterDescriptor> valueParameters,
             @NotNull List<TypeParameterDescriptor> typeParameters
     ) {
-        return new SignaturesPropagationData(owner, returnType, receiverType, valueParameters, typeParameters, method, trace);
+        SignaturesPropagationData data =
+                new SignaturesPropagationData(owner, returnType, receiverType, valueParameters, typeParameters, method, trace);
+        return new PropagatedMethodSignature(data.getModifiedReturnType(), data.getModifiedReceiverType(),
+                                             data.getModifiedValueParameters(), data.getModifiedTypeParameters(), data.getSignatureErrors(),
+                                             data.getSuperFunctions());
     }
 
     @SuppressWarnings("MethodMayBeStatic")
@@ -138,10 +160,10 @@ public class ExternalSignatureResolver {
 
         if (data.isAnnotated() && !data.hasErrors()) {
             return new AlternativeMethodSignature(data.getReturnType(), receiverType, data.getValueParameters(), data.getTypeParameters(),
-                                                  null);
+                                                  Collections.<String>emptyList());
         }
 
-        String error = data.hasErrors() ? data.getError() : null;
+        List<String> error = data.hasErrors() ? Collections.singletonList(data.getError()) : Collections.<String>emptyList();
         return new AlternativeMethodSignature(returnType, receiverType, valueParameters, typeParameters, error);
     }
 

compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/resolver/JavaFunctionResolver.java

@@ -36,7 +36,6 @@ import org.jetbrains.jet.lang.resolve.java.descriptor.ClassDescriptorFromJvmByte
 import org.jetbrains.jet.lang.resolve.java.descriptor.JavaMethodDescriptor;
 import org.jetbrains.jet.lang.resolve.java.descriptor.SamAdapterDescriptor;
 import org.jetbrains.jet.lang.resolve.java.descriptor.SamConstructorDescriptor;
-import org.jetbrains.jet.lang.resolve.java.kotlinSignature.SignaturesPropagationData;
 import org.jetbrains.jet.lang.resolve.java.kotlinSignature.SignaturesUtil;
 import org.jetbrains.jet.lang.resolve.java.scope.NamedMembers;
 import org.jetbrains.jet.lang.resolve.java.structure.JavaMethod;
@@ -148,18 +147,18 @@ public final class JavaFunctionResolver {
             signatureErrors = effectiveSignature.getErrors();
         }
         else if (ownerDescriptor instanceof ClassDescriptor) {
-            SignaturesPropagationData propagated = externalSignatureResolver
+            ExternalSignatureResolver.PropagatedMethodSignature propagated = externalSignatureResolver
                     .resolvePropagatedSignature(method, (ClassDescriptor) ownerDescriptor, returnType, null, valueParameters,
                                                 methodTypeParameters);
 
-            superFunctions = propagated.getSuperFunctions();
+            superFunctions = propagated.getSuperMethods();
 
             effectiveSignature = externalSignatureResolver
-                    .resolveAlternativeMethodSignature(method, !superFunctions.isEmpty(), propagated.getModifiedReturnType(),
+                    .resolveAlternativeMethodSignature(method, !superFunctions.isEmpty(), propagated.getReturnType(),
-                                                       propagated.getModifiedReceiverType(), propagated.getModifiedValueParameters(),
+                                                       propagated.getReceiverType(), propagated.getValueParameters(),
-                                                       propagated.getModifiedTypeParameters());
+                                                       propagated.getTypeParameters());
 
-            signatureErrors = new ArrayList<String>(propagated.getSignatureErrors());
+            signatureErrors = new ArrayList<String>(propagated.getErrors());
             signatureErrors.addAll(effectiveSignature.getErrors());
         }
         else {