Change Signature: Translate JetChangeInfo to Kotlin

idea/src/org/jetbrains/jet/plugin/refactoring/changeSignature/JetChangeInfo.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2013 JetBrains s.r.o.
+ * Copyright 2010-2014 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.
@@ -14,312 +14,177 @@
  * limitations under the License.
  */
 
-package org.jetbrains.jet.plugin.refactoring.changeSignature;
+package org.jetbrains.jet.plugin.refactoring.changeSignature
 
-import com.intellij.lang.Language;
-import com.intellij.openapi.util.text.StringUtil;
-import com.intellij.psi.PsiElement;
-import com.intellij.psi.PsiMethod;
-import com.intellij.psi.PsiModifier;
-import com.intellij.psi.PsiType;
-import com.intellij.refactoring.changeSignature.*;
-import com.intellij.usageView.UsageInfo;
-import com.intellij.util.Function;
-import com.intellij.util.VisibilityUtil;
-import com.intellij.util.containers.ContainerUtil;
-import kotlin.Function1;
-import kotlin.KotlinPackage;
-import kotlin.Pair;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-import org.jetbrains.jet.asJava.AsJavaPackage;
-import org.jetbrains.jet.lang.descriptors.FunctionDescriptor;
-import org.jetbrains.jet.lang.descriptors.ValueParameterDescriptor;
-import org.jetbrains.jet.lang.descriptors.Visibilities;
-import org.jetbrains.jet.lang.descriptors.Visibility;
-import org.jetbrains.jet.lang.psi.JetFunction;
-import org.jetbrains.jet.lang.psi.JetFunctionLiteral;
-import org.jetbrains.jet.lang.resolve.DescriptorToSourceUtils;
-import org.jetbrains.jet.lang.types.JetType;
-import org.jetbrains.jet.lang.types.TypeSubstitutor;
-import org.jetbrains.jet.lang.types.lang.KotlinBuiltIns;
-import org.jetbrains.jet.lexer.JetTokens;
-import org.jetbrains.jet.plugin.JetLanguage;
-import org.jetbrains.jet.plugin.caches.resolve.ResolvePackage;
-import org.jetbrains.jet.plugin.refactoring.changeSignature.usages.JetFunctionDefinitionUsage;
-import org.jetbrains.jet.plugin.util.IdeDescriptorRenderers;
+import com.intellij.lang.Language
+import com.intellij.openapi.util.text.StringUtil
+import com.intellij.psi.PsiElement
+import com.intellij.psi.PsiMethod
+import com.intellij.psi.PsiModifier
+import com.intellij.psi.PsiType
+import com.intellij.refactoring.changeSignature.*
+import com.intellij.usageView.UsageInfo
+import com.intellij.util.Function
+import com.intellij.util.VisibilityUtil
+import com.intellij.util.containers.ContainerUtil
+import kotlin.Function1
+import kotlin.Pair
+import org.jetbrains.jet.asJava.*
+import org.jetbrains.jet.lang.descriptors.FunctionDescriptor
+import org.jetbrains.jet.lang.descriptors.ValueParameterDescriptor
+import org.jetbrains.jet.lang.descriptors.Visibilities
+import org.jetbrains.jet.lang.descriptors.Visibility
+import org.jetbrains.jet.lang.psi.JetFunction
+import org.jetbrains.jet.lang.psi.JetFunctionLiteral
+import org.jetbrains.jet.lang.resolve.DescriptorToSourceUtils
+import org.jetbrains.jet.lang.types.JetType
+import org.jetbrains.jet.lang.types.TypeSubstitutor
+import org.jetbrains.jet.lang.types.lang.KotlinBuiltIns
+import org.jetbrains.jet.lexer.JetTokens
+import org.jetbrains.jet.plugin.JetLanguage
+import org.jetbrains.jet.plugin.caches.resolve.*
+import org.jetbrains.jet.plugin.refactoring.changeSignature.usages.JetFunctionDefinitionUsage
+import org.jetbrains.jet.plugin.util.IdeDescriptorRenderers
+import java.util.HashMap
+import kotlin.properties.Delegates
 
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+public class JetChangeInfo(
+        val methodDescriptor: JetMethodDescriptor,
+        private var name: String,
+        val newReturnType: JetType?,
+        var newReturnTypeText: String,
+        var newVisibility: Visibility,
+        parameterInfos: List<JetParameterInfo>,
+        val context: PsiElement
+): ChangeInfo {
+    private val newParameters = parameterInfos.toArrayList()
+    private val originalPsiMethod: PsiMethod? = getCurrentPsiMethod()
 
-public class JetChangeInfo implements ChangeInfo {
-    private final JetMethodDescriptor oldDescriptor;
-    private String newName;
-    private final JetType newReturnType;
-    private String newReturnTypeText;
-    private Visibility newVisibility;
-    private final List<JetParameterInfo> newParameters;
-    private final PsiElement context;
-    private Boolean parameterNamesChanged;
-    private Map<String, Integer> oldNameToParameterIndex;
-    private boolean primaryMethodUpdated;
-    @Nullable
-    private JavaChangeInfo javaChangeInfo;
-    private final PsiMethod originalPsiMethod;
+    private val oldNameToParameterIndex: Map<String, Int> by Delegates.lazy {
+        val map = HashMap<String, Int>()
 
-    public JetChangeInfo(
-            JetMethodDescriptor oldDescriptor,
-            String newName,
-            JetType newReturnType,
-            String newReturnTypeText,
-            Visibility newVisibility,
-            List<JetParameterInfo> newParameters,
-            PsiElement context
-    ) {
-        this.oldDescriptor = oldDescriptor;
-        this.newName = newName;
-        this.newReturnType = newReturnType;
-        this.newReturnTypeText = newReturnTypeText;
-        this.newVisibility = newVisibility;
-        this.newParameters = newParameters;
-        this.context = context;
-        this.originalPsiMethod = getCurrentPsiMethod();
+        val parameters = methodDescriptor.baseDescriptor.getValueParameters()
+        parameters.indices.forEach { i -> map[parameters.get(i).getName().asString()] = i }
+
+        map
     }
 
-    @Nullable
-    private PsiMethod getCurrentPsiMethod() {
-        List<PsiMethod> psiMethods = AsJavaPackage.toLightMethods(getMethod());
-        assert psiMethods.size() <= 1 : "Multiple light methods: " + getMethod().getText();
-        return KotlinPackage.firstOrNull(psiMethods);
+    public val isParameterSetOrOrderChanged: Boolean by Delegates.lazy {
+        newParameters.size() != methodDescriptor.getParametersCount() ||
+        newParameters.indices.any { i -> newParameters.get(i).getOldIndex() != i }
     }
 
-    public String getNewSignature(@NotNull JetFunctionDefinitionUsage inheritedFunction) {
-        StringBuilder buffer = new StringBuilder();
+    private var isPrimaryMethodUpdated: Boolean = false
+    private var javaChangeInfo: JavaChangeInfo? = null
 
-        if (isConstructor()) {
-            buffer.append(newName);
-
-            if (newVisibility != null && newVisibility != Visibilities.PUBLIC)
-                buffer.append(' ').append(newVisibility.toString()).append(' ');
-        }
-        else {
-            if (newVisibility != null && newVisibility != Visibilities.INTERNAL)
-                buffer.append(newVisibility.toString()).append(' ');
-
-            buffer.append(JetTokens.FUN_KEYWORD).append(' ').append(newName);
-        }
-
-        buffer.append(getNewParametersSignature(inheritedFunction, buffer.length()));
-
-        if (newReturnType != null && !KotlinBuiltIns.isUnit(newReturnType) && !isConstructor())
-            buffer.append(": ").append(newReturnTypeText);
-
-        return buffer.toString();
+    private fun getCurrentPsiMethod(): PsiMethod? {
+        val psiMethods = getMethod().toLightMethods()
+        assert(psiMethods.size() <= 1) { "Multiple light methods: " + getMethod().getText() }
+        return psiMethods.firstOrNull()
     }
 
-    public boolean isRefactoringTarget(FunctionDescriptor inheritedFunctionDescriptor) {
-        return inheritedFunctionDescriptor != null &&
-               getMethod() == DescriptorToSourceUtils.descriptorToDeclaration(inheritedFunctionDescriptor);
+    public fun getOldParameterIndex(oldParameterName: String): Int? = oldNameToParameterIndex[oldParameterName]
+
+    override fun isParameterTypesChanged(): Boolean = true
+
+    override fun isParameterNamesChanged(): Boolean = true
+
+    override fun isParameterSetOrOrderChanged(): Boolean = isParameterSetOrOrderChanged
+
+    public fun getNewParametersCount(): Int = newParameters.size()
+
+    override fun getNewParameters(): Array<JetParameterInfo> = newParameters.copyToArray()
+
+    public fun setNewParameter(index: Int, parameterInfo: JetParameterInfo) {
+        newParameters.set(index, parameterInfo)
     }
 
-    public String getNewParametersSignature(
-            @NotNull JetFunctionDefinitionUsage inheritedFunction,
-            int indentLength
-    ) {
-        boolean isLambda = inheritedFunction.getDeclaration() instanceof JetFunctionLiteral;
-        if (isLambda && newParameters.size() == 1 && !newParameters.get(0).requiresExplicitType(inheritedFunction)) {
-            return newParameters.get(0).getDeclarationSignature(0, inheritedFunction);
-        }
-
-        StringBuilder buffer = new StringBuilder("(");
-        String indent = StringUtil.repeatSymbol(' ', indentLength + 1);
-
-        for (int i = 0; i < newParameters.size(); i++) {
-            JetParameterInfo parameterInfo = newParameters.get(i);
-            if (i > 0) {
-                buffer.append(",");
-                buffer.append(indent);
-            }
-
-            buffer.append(parameterInfo.getDeclarationSignature(i, inheritedFunction));
-        }
-
-        buffer.append(")");
-        return buffer.toString();
+    public fun addParameter(parameterInfo: JetParameterInfo) {
+        newParameters.add(parameterInfo)
     }
 
-    private boolean innerParameterSetOrOrderChanged() {
-        if (newParameters.size() != oldDescriptor.getParametersCount())
-            return true;
-
-        for (int i = 0; i < newParameters.size(); i ++) {
-            if (newParameters.get(i).getOldIndex() != i)
-                return true;
-        }
-
-        return false;
-    }
-
-    private Map<String, Integer> initOldNameToParameterIndex() {
-        Map<String, Integer> map = new HashMap<String, Integer>();
-        FunctionDescriptor descriptor = oldDescriptor.getBaseDescriptor();
-
-        if (descriptor != null) {
-            List<ValueParameterDescriptor> parameters = descriptor.getValueParameters();
-
-            for (int i = 0; i < parameters.size(); i++) {
-                ValueParameterDescriptor oldParameter = parameters.get(i);
-                map.put(oldParameter.getName().asString(), i);
-            }
-        }
-
-        return map;
-    }
-
-    public int getNewParametersCount() {
-        return newParameters.size();
-    }
-
-    @NotNull
-    @Override
-    public JetParameterInfo[] getNewParameters() {
-        return newParameters.toArray(new JetParameterInfo[newParameters.size()]);
-    }
-
-    public void setNewParameter(int index, JetParameterInfo parameterInfo) {
-        newParameters.set(index, parameterInfo);
-    }
-
-    public void addParameter(JetParameterInfo parameterInfo) {
-        newParameters.add(parameterInfo);
-    }
-
-    public void removeParameter(int index) {
+    public fun removeParameter(index: Int) {
         newParameters.remove(index);
     }
 
-    @Override
-    public boolean isParameterSetOrOrderChanged() {
-        if (parameterNamesChanged == null)
-            parameterNamesChanged = innerParameterSetOrOrderChanged();
+    override fun isGenerateDelegate(): Boolean = false
 
-        return parameterNamesChanged;
+    override fun getNewName(): String = name
+
+    fun setNewName(value: String) {
+        name = value
     }
 
-    @Nullable
-    public Integer getOldParameterIndex(String oldParameterName) {
-        if (oldNameToParameterIndex == null)
-            oldNameToParameterIndex = initOldNameToParameterIndex();
+    override fun isNameChanged(): Boolean = name != methodDescriptor.getName()
 
-        return oldNameToParameterIndex.get(oldParameterName);
+    public fun isVisibilityChanged(): Boolean = newVisibility != methodDescriptor.getVisibility()
+
+    override fun getMethod(): PsiElement {
+        return methodDescriptor.getMethod()
     }
 
-    @Override
-    public boolean isParameterTypesChanged() {
-        return true;
+    override fun isReturnTypeChanged(): Boolean = newReturnTypeText != methodDescriptor.renderOriginalReturnType()
+
+    override fun getLanguage(): Language = JetLanguage.INSTANCE
+
+    public fun getNewSignature(inheritedFunction: JetFunctionDefinitionUsage<PsiElement>): String {
+        val buffer = StringBuilder()
+
+        if (isConstructor) {
+            buffer.append(name)
+
+            if (newVisibility != Visibilities.PUBLIC) {
+                buffer.append(' ').append(newVisibility).append(' ')
+            }
+        }
+        else {
+            if (newVisibility != Visibilities.INTERNAL) {
+                buffer.append(newVisibility).append(' ')
+            }
+
+            buffer.append(JetTokens.FUN_KEYWORD).append(' ').append(name)
+        }
+
+        buffer.append(getNewParametersSignature(inheritedFunction, buffer.length()))
+
+        if (newReturnType != null && !KotlinBuiltIns.isUnit(newReturnType) && !isConstructor)
+            buffer.append(": ").append(newReturnTypeText)
+
+        return buffer.toString()
     }
 
-    @Override
-    public boolean isParameterNamesChanged() {
-        return true;
+    public fun isRefactoringTarget(inheritedFunctionDescriptor: FunctionDescriptor?): Boolean {
+        return inheritedFunctionDescriptor != null
+               && getMethod() == DescriptorToSourceUtils.descriptorToDeclaration(inheritedFunctionDescriptor)
     }
 
-    @Override
-    public boolean isGenerateDelegate() {
-        return false;
+    public fun getNewParametersSignature(inheritedFunction: JetFunctionDefinitionUsage<PsiElement>, indentLength: Int): String {
+        val isLambda = inheritedFunction.getDeclaration() is JetFunctionLiteral
+        if (isLambda && newParameters.size() == 1 && !newParameters.get(0).requiresExplicitType(inheritedFunction)) {
+            return newParameters.get(0).getDeclarationSignature(0, inheritedFunction)
+        }
+
+        val indent = StringUtil.repeatSymbol(' ', indentLength + 1)
+        return newParameters.indices
+                .map { i -> newParameters[i].getDeclarationSignature(i, inheritedFunction) }
+                .joinToString(prefix = "(", separator = ",$indent", postfix = ")")
     }
 
-    public void setNewName(String newName) {
-        this.newName = newName;
+    public fun renderReturnType(inheritedFunction: JetFunctionDefinitionUsage<PsiElement>): String {
+        val typeSubstitutor = inheritedFunction.getOrCreateTypeSubstitutor() ?: return newReturnTypeText
+        val currentBaseFunction = inheritedFunction.getBaseFunction().getCurrentFunctionDescriptor() ?: return newReturnTypeText
+        return currentBaseFunction.getReturnType().renderTypeWithSubstitution(typeSubstitutor, newReturnTypeText, false)
     }
 
-    @Override
-    public boolean isNameChanged() {
-        return !newName.equals(oldDescriptor.getName());
+    public fun primaryMethodUpdated() {
+        isPrimaryMethodUpdated = true
+        javaChangeInfo = null
     }
 
-    public boolean isVisibilityChanged() {
-        return !newVisibility.equals(oldDescriptor.getVisibility());
-    }
-
-    public Visibility getNewVisibility() {
-        return newVisibility;
-    }
-
-    public void setNewVisibility(Visibility newVisibility) {
-        this.newVisibility = newVisibility;
-    }
-
-    @Override
-    public PsiElement getMethod() {
-        return oldDescriptor.getMethod();
-    }
-
-    @Nullable
-    public FunctionDescriptor getOldDescriptor() {
-        return oldDescriptor.getBaseDescriptor();
-    }
-
-    public JetMethodDescriptor getFunctionDescriptor() {
-        return oldDescriptor;
-    }
-
-    public boolean isConstructor() {
-        return ChangeSignaturePackage.getIsConstructor(oldDescriptor);
-    }
-
-    public void setNewReturnTypeText(String newReturnTypeText) {
-        this.newReturnTypeText = newReturnTypeText;
-    }
-
-    @Override
-    public boolean isReturnTypeChanged() {
-        return !newReturnTypeText.equals(ChangeSignaturePackage.renderOriginalReturnType(oldDescriptor));
-    }
-
-    @Nullable
-    public String getOldName() {
-        PsiElement function = oldDescriptor.getMethod();
-        return function instanceof JetFunction ? ((JetFunction) function).getName() : null;
-    }
-
-    @Override
-    public String getNewName() {
-        return newName;
-    }
-
-    public PsiElement getContext() {
-        return context;
-    }
-
-    @Override
-    public Language getLanguage() {
-        return JetLanguage.INSTANCE;
-    }
-
-    @NotNull
-    public Collection<UsageInfo> getAffectedFunctions() {
-        return oldDescriptor.getAffectedFunctions();
-    }
-
-    public String renderReturnType(@NotNull JetFunctionDefinitionUsage inheritedFunction) {
-        TypeSubstitutor typeSubstitutor = inheritedFunction.getOrCreateTypeSubstitutor();
-        if (typeSubstitutor == null) return newReturnTypeText;
-
-        FunctionDescriptor currentBaseFunction = inheritedFunction.getBaseFunction().getCurrentFunctionDescriptor();
-        if (currentBaseFunction == null) return newReturnTypeText;
-
-        JetType originalType = currentBaseFunction.getReturnType();
-        return ChangeSignaturePackage.renderTypeWithSubstitution(originalType, typeSubstitutor, newReturnTypeText, false);
-    }
-
-    @Nullable
-    public JavaChangeInfo getOrCreateJavaChangeInfo() {
+    public fun getOrCreateJavaChangeInfo(): JavaChangeInfo? {
         if (javaChangeInfo == null) {
-            final PsiMethod currentPsiMethod = getCurrentPsiMethod();
-            if (originalPsiMethod == null || currentPsiMethod == null) return null;
+            val currentPsiMethod = getCurrentPsiMethod()
+            if (originalPsiMethod == null || currentPsiMethod == null) return null
 
             /*
              * When primaryMethodUpdated is false, changes to the primary Kotlin declaration are already confirmed, but not yet applied.
@@ -328,94 +193,77 @@ public class JetChangeInfo implements ChangeInfo {
              * to use in JavaChangeInfo. However they are not actually used at this point since only parameter count and order matters here
              * So we resort to this hack and pass around "default" type (void) and visibility (package-local)
              */
-            String javaVisibility = primaryMethodUpdated
-                                    ? VisibilityUtil.getVisibilityModifier(currentPsiMethod.getModifierList())
-                                    : PsiModifier.PACKAGE_LOCAL;
+            val javaVisibility = if (isPrimaryMethodUpdated)
+                VisibilityUtil.getVisibilityModifier(currentPsiMethod.getModifierList())
+            else
+                PsiModifier.PACKAGE_LOCAL
 
-            JetParameterInfo[] newParameters = getNewParameters();
-            ParameterInfoImpl[] newJavaParameters = ContainerUtil.map2Array(
-                    KotlinPackage.withIndices(newParameters),
-                    new ParameterInfoImpl[newParameters.length],
-                    new Function<Pair<? extends Integer, ? extends JetParameterInfo>, ParameterInfoImpl>() {
-                        @Override
-                        public ParameterInfoImpl fun(Pair<? extends Integer, ? extends JetParameterInfo> pair) {
-                            JetParameterInfo info = pair.getSecond();
-                            PsiType type = primaryMethodUpdated
-                                           ? currentPsiMethod.getParameterList().getParameters()[pair.getFirst()].getType()
-                                           : PsiType.VOID;
-                            return new ParameterInfoImpl(info.getOldIndex(), info.getName(), type, info.getDefaultValueForCall());
-                        }
-                    }
-            );
+            val newJavaParameters = newParameters.withIndices().map { pair ->
+                val (i, info) = pair
+                val type = if (isPrimaryMethodUpdated)
+                    currentPsiMethod.getParameterList().getParameters()[i].getType()
+                else
+                    PsiType.VOID
+                ParameterInfoImpl(info.getOldIndex(), info.getName(), type, info.defaultValueForCall)
+            }.copyToArray()
 
-            PsiType returnType = primaryMethodUpdated ? currentPsiMethod.getReturnType() : PsiType.VOID;
+            val returnType = if (isPrimaryMethodUpdated) currentPsiMethod.getReturnType() else PsiType.VOID
 
-            javaChangeInfo = new ChangeSignatureProcessor(
-                    getMethod().getProject(), originalPsiMethod, false, javaVisibility, getNewName(), returnType, newJavaParameters
-            ).getChangeInfo();
-            javaChangeInfo.updateMethod(currentPsiMethod);
+            javaChangeInfo = ChangeSignatureProcessor(getMethod().getProject(),
+                                                      originalPsiMethod,
+                                                      false,
+                                                      javaVisibility,
+                                                      getNewName(),
+                                                      returnType,
+                                                      newJavaParameters).getChangeInfo()
+            javaChangeInfo!!.updateMethod(currentPsiMethod)
         }
 
-        return javaChangeInfo;
-    }
-
-    public void primaryMethodUpdated() {
-        primaryMethodUpdated = true;
-        javaChangeInfo = null;
-    }
-
-    @NotNull
-    public static JetChangeInfo fromJavaChangeInfo(
-            @NotNull ChangeInfo javaChangeInfo,
-            @NotNull JetMethodDescriptor originalChangeSignatureDescriptor
-    ) {
-        PsiMethod method = (PsiMethod) javaChangeInfo.getMethod();
-
-        FunctionDescriptor functionDescriptor = ResolvePackage.getJavaMethodDescriptor(method);
-        final List<ValueParameterDescriptor> parameterDescriptors = functionDescriptor.getValueParameters();
-
-        //noinspection ConstantConditions
-        final List<ValueParameterDescriptor> originalParameterDescriptors =
-                originalChangeSignatureDescriptor.getBaseDescriptor().getValueParameters();
-
-
-        List<JetParameterInfo> newParameters = KotlinPackage.map(
-                KotlinPackage.withIndices(javaChangeInfo.getNewParameters()),
-                new Function1<Pair<? extends Integer, ? extends ParameterInfo>, JetParameterInfo>() {
-                    @Override
-                    public JetParameterInfo invoke(Pair<? extends Integer, ? extends ParameterInfo> pair) {
-                        ParameterInfo info = pair.getSecond();
-                        int oldIndex = info.getOldIndex();
-                        JetType currentType = parameterDescriptors.get(pair.getFirst()).getType();
-                        JetType originalType = oldIndex >= 0
-                                               ? originalParameterDescriptors.get(oldIndex).getType()
-                                               : currentType;
-                        String defaultValue = info.getDefaultValue();
-
-                        JetParameterInfo jetParameterInfo =
-                                new JetParameterInfo(oldIndex,
-                                                     info.getName(),
-                                                     originalType, null,
-                                                     defaultValue != null ? defaultValue : "",
-                                                     null,
-                                                     null);
-                        jetParameterInfo.setCurrentTypeText(IdeDescriptorRenderers.SOURCE_CODE.renderType(currentType));
-                        return jetParameterInfo;
-                    }
-                }
-        );
-
-        JetType returnType = functionDescriptor.getReturnType();
-        String returnTypeText = returnType != null ? IdeDescriptorRenderers.SOURCE_CODE.renderType(returnType) : "";
-
-        return new JetChangeInfo(
-                originalChangeSignatureDescriptor,
-                javaChangeInfo.getNewName(),
-                returnType,
-                returnTypeText,
-                functionDescriptor.getVisibility(),
-                newParameters,
-                method
-        );
+        return javaChangeInfo
     }
 }
+
+public val JetChangeInfo.originalBaseFunctionDescriptor: FunctionDescriptor
+    get() = methodDescriptor.baseDescriptor
+
+public val JetChangeInfo.isConstructor: Boolean get() = methodDescriptor.isConstructor
+
+public val JetChangeInfo.oldName: String?
+    get() = (methodDescriptor.getMethod() as? JetFunction)?.getName()
+
+public val JetChangeInfo.affectedFunctions: Collection<UsageInfo> get() = methodDescriptor.affectedFunctions
+
+public fun ChangeInfo.toJetChangeInfo(originalChangeSignatureDescriptor: JetMethodDescriptor): JetChangeInfo {
+    val method = getMethod() as PsiMethod
+
+    val functionDescriptor = method.getJavaMethodDescriptor()
+    val parameterDescriptors = functionDescriptor.getValueParameters()
+
+    //noinspection ConstantConditions
+    val originalParameterDescriptors = originalChangeSignatureDescriptor.baseDescriptor.getValueParameters()
+
+    val newParameters = getNewParameters().withIndices().map { pair ->
+        val (i, info) = pair
+        val oldIndex = info.getOldIndex()
+        val currentType = parameterDescriptors[i].getType()
+
+        with(JetParameterInfo(originalIndex = oldIndex,
+                              name = info.getName(),
+                              type = if (oldIndex >= 0) originalParameterDescriptors[oldIndex].getType() else currentType,
+                              defaultValueForCall = info.getDefaultValue() ?: "")) {
+            currentTypeText = IdeDescriptorRenderers.SOURCE_CODE.renderType(currentType)
+            this
+        }
+    }
+
+    val returnType = functionDescriptor.getReturnType()
+    val returnTypeText = if (returnType != null) IdeDescriptorRenderers.SOURCE_CODE.renderType(returnType) else ""
+
+    return JetChangeInfo(originalChangeSignatureDescriptor,
+                          getNewName(),
+                          returnType,
+                          returnTypeText,
+                          functionDescriptor.getVisibility(),
+                          newParameters,
+                          method)
+}

idea/src/org/jetbrains/jet/plugin/refactoring/changeSignature/JetChangeSignatureProcessor.java

@@ -48,7 +48,7 @@ public class JetChangeSignatureProcessor extends ChangeSignatureProcessorBase {
     @NotNull
     @Override
     protected UsageViewDescriptor createUsageViewDescriptor(UsageInfo[] usages) {
-        String subject = getChangeInfo().isConstructor() ? "constructor" : "function";
+        String subject = ChangeSignaturePackage.getIsConstructor(getChangeInfo()) ? "constructor" : "function";
         return new JetUsagesViewDescriptor(myChangeInfo.getMethod(), RefactoringBundle.message("0.to.change.signature", subject));
     }
 

idea/src/org/jetbrains/jet/plugin/refactoring/changeSignature/JetChangeSignatureUsageProcessor.java

@@ -69,7 +69,7 @@ public class JetChangeSignatureUsageProcessor implements ChangeSignatureUsagePro
     }
 
     private static void findAllMethodUsages(JetChangeInfo changeInfo, Set<UsageInfo> result) {
-        for (UsageInfo functionUsageInfo : changeInfo.getAffectedFunctions()) {
+        for (UsageInfo functionUsageInfo : ChangeSignaturePackage.getAffectedFunctions(changeInfo)) {
             if (functionUsageInfo instanceof JetFunctionDefinitionUsage) {
                 findOneMethodUsages((JetFunctionDefinitionUsage) functionUsageInfo, changeInfo, result);
             }
@@ -111,7 +111,7 @@ public class JetChangeSignatureUsageProcessor implements ChangeSignatureUsagePro
             }
         }
 
-        String oldName = changeInfo.getOldName();
+        String oldName = ChangeSignaturePackage.getOldName(changeInfo);
 
         if (oldName != null)
             TextOccurrencesUtil.findNonCodeUsages(functionPsi, oldName, true, true, changeInfo.getNewName(), result);
@@ -203,7 +203,7 @@ public class JetChangeSignatureUsageProcessor implements ChangeSignatureUsagePro
         PsiElement function = info.getMethod();
         PsiElement element = function != null ? function : changeInfo.getContext();
         BindingContext bindingContext = ResolvePackage.analyze((JetElement) element);
-        FunctionDescriptor oldDescriptor = changeInfo.getOldDescriptor();
+        FunctionDescriptor oldDescriptor = ChangeSignaturePackage.getOriginalBaseFunctionDescriptor(changeInfo);
         JetScope parametersScope = null;
         DeclarationDescriptor containingDeclaration = oldDescriptor != null ? oldDescriptor.getContainingDeclaration() : null;
 
@@ -214,7 +214,7 @@ public class JetChangeSignatureUsageProcessor implements ChangeSignatureUsagePro
 
         JetScope functionScope = getFunctionScope(bindingContext, containingDeclaration);
 
-        if (!changeInfo.isConstructor() && functionScope != null && !info.getNewName().isEmpty()) {
+        if (!ChangeSignaturePackage.getIsConstructor(changeInfo) && functionScope != null && !info.getNewName().isEmpty()) {
             for (FunctionDescriptor conflict : functionScope.getFunctions(Name.identifier(info.getNewName()))) {
                 if (conflict == oldDescriptor) continue;
 
@@ -236,7 +236,7 @@ public class JetChangeSignatureUsageProcessor implements ChangeSignatureUsagePro
                 result.putValue(element, "Duplicating parameter '" + parameterName + "'");
             }
             if (parametersScope != null) {
-                if (changeInfo.isConstructor() && valOrVar != JetValVar.None) {
+                if (ChangeSignaturePackage.getIsConstructor(changeInfo) && valOrVar != JetValVar.None) {
                     for (VariableDescriptor property : parametersScope.getProperties(Name.identifier(parameterName))) {
                         PsiElement propertyDeclaration = DescriptorToSourceUtils.descriptorToDeclaration(property);
 
@@ -320,7 +320,7 @@ public class JetChangeSignatureUsageProcessor implements ChangeSignatureUsagePro
                 private final JetFunctionDefinitionUsage<JetFunction> delegateUsage = new JetFunctionDefinitionUsage<JetFunction>(
                         samUsage.getFunctionLiteral(),
                         samUsage.getFunctionDescriptor(),
-                        javaMethodChangeInfo.getFunctionDescriptor().getOriginalPrimaryFunction(),
+                        javaMethodChangeInfo.getMethodDescriptor().getOriginalPrimaryFunction(),
                         samUsage.getSamCallType()
                 );
 
@@ -453,7 +453,7 @@ public class JetChangeSignatureUsageProcessor implements ChangeSignatureUsagePro
         if (element == null) return false;
 
         if (isJavaMethodUsage && originalJavaMethodDescriptor != null) {
-            JetChangeInfo javaMethodChangeInfo = JetChangeInfo.fromJavaChangeInfo(changeInfo, originalJavaMethodDescriptor);
+            JetChangeInfo javaMethodChangeInfo = ChangeSignaturePackage.toJetChangeInfo(changeInfo, originalJavaMethodDescriptor);
             originalJavaMethodDescriptor = null;
 
             for (int i = 0; i < usages.length; i++) {
@@ -493,7 +493,7 @@ public class JetChangeSignatureUsageProcessor implements ChangeSignatureUsagePro
         if (!(changeInfo instanceof JetChangeInfo)) return false;
 
         JetChangeInfo jetChangeInfo = (JetChangeInfo) changeInfo;
-        for (JetFunctionDefinitionUsage primaryFunction : jetChangeInfo.getFunctionDescriptor().getPrimaryFunctions()) {
+        for (JetFunctionDefinitionUsage primaryFunction : jetChangeInfo.getMethodDescriptor().getPrimaryFunctions()) {
             primaryFunction.processUsage(jetChangeInfo, primaryFunction.getDeclaration());
         }
         jetChangeInfo.primaryMethodUpdated();

idea/src/org/jetbrains/jet/plugin/refactoring/changeSignature/usages/JavaMethodKotlinUsageWithDelegate.kt

@@ -35,7 +35,7 @@ public abstract class JavaMethodKotlinUsageWithDelegate<T: PsiElement>(
 public class JavaMethodKotlinCallUsage(
         callElement: JetCallElement,
         javaMethodChangeInfo: JetChangeInfo): JavaMethodKotlinUsageWithDelegate<JetCallElement>(callElement, javaMethodChangeInfo) {
-    override protected val delegateUsage = JetFunctionCallUsage(psiElement, javaMethodChangeInfo.getFunctionDescriptor().originalPrimaryFunction)
+    override protected val delegateUsage = JetFunctionCallUsage(psiElement, javaMethodChangeInfo.methodDescriptor.originalPrimaryFunction)
 }
 
 public class JavaMethodKotlinDerivedDefinitionUsage(
@@ -46,7 +46,7 @@ public class JavaMethodKotlinDerivedDefinitionUsage(
     override protected val delegateUsage = JetFunctionDefinitionUsage(
             psiElement,
             functionDescriptor,
-            javaMethodChangeInfo.getFunctionDescriptor().originalPrimaryFunction,
+            javaMethodChangeInfo.methodDescriptor.originalPrimaryFunction,
             null
     )
 }

idea/src/org/jetbrains/jet/plugin/refactoring/changeSignature/usages/JetEnumEntryWithoutSuperCallUsage.kt

@@ -35,7 +35,7 @@ public class JetEnumEntryWithoutSuperCallUsage(enumEntry: JetEnumEntry) : JetUsa
             ) as JetDelegatorToSuperCall
             element.addBefore(psiFactory.createColon(), delegatorToSuperCall)
 
-            return JetFunctionCallUsage(delegatorToSuperCall, changeInfo.getFunctionDescriptor().originalPrimaryFunction)
+            return JetFunctionCallUsage(delegatorToSuperCall, changeInfo.methodDescriptor.originalPrimaryFunction)
                     .processUsage(changeInfo, delegatorToSuperCall)
         }
 

idea/src/org/jetbrains/jet/plugin/refactoring/changeSignature/usages/JetFunctionDefinitionUsage.java

@@ -175,7 +175,7 @@ public class JetFunctionDefinitionUsage<T extends PsiElement> extends JetUsageIn
                                          || function.getTypeReference() != null;
             if (changeInfo.isReturnTypeChanged() && returnTypeIsNeeded) {
                 function.setTypeReference(null);
-                String returnTypeText = changeInfo.renderReturnType(this);
+                String returnTypeText = changeInfo.renderReturnType((JetFunctionDefinitionUsage<PsiElement>) this);
 
                 //TODO use ChangeFunctionReturnTypeFix.invoke when JetTypeCodeFragment.getType() is ready
                 if (!KotlinBuiltIns.getInstance().getUnitType().toString().equals(returnTypeText)) {
@@ -203,11 +203,15 @@ public class JetFunctionDefinitionUsage<T extends PsiElement> extends JetUsageIn
                     }
                 }
                 else {
-                    newParameterList = psiFactory.createFunctionLiteralParameterList(changeInfo.getNewParametersSignature(this, 0));
+                    newParameterList = psiFactory.createFunctionLiteralParameterList(changeInfo.getNewParametersSignature(
+                            (JetFunctionDefinitionUsage<PsiElement>) this, 0)
+                    );
                 }
             }
             else {
-                newParameterList = psiFactory.createParameterList(changeInfo.getNewParametersSignature(this, 0));
+                newParameterList = psiFactory.createParameterList(changeInfo.getNewParametersSignature(
+                        (JetFunctionDefinitionUsage<PsiElement>) this, 0)
+                );
             }
 
             if (newParameterList != null) {

idea/tests/org/jetbrains/jet/plugin/refactoring/changeSignature/JetChangeSignatureTest.java

@@ -241,7 +241,7 @@ public class JetChangeSignatureTest extends KotlinCodeInsightTestCase {
             BindingContext context = ResolvePackage.analyze(method);
 
             ChangeSignaturePackage
-                    .runChangeSignature(getProject(), changeInfo.getOldDescriptor(), empty, context, method, "test");
+                    .runChangeSignature(getProject(), ChangeSignaturePackage.getOriginalBaseFunctionDescriptor(changeInfo), empty, context, method, "test");
         }
         catch (RuntimeException e) {
             assertTrue(e.getMessage().startsWith("Refactoring cannot be"));
@@ -318,7 +318,8 @@ public class JetChangeSignatureTest extends KotlinCodeInsightTestCase {
     public void testFunctionJavaUsagesAndOverridesAddParam() throws Exception {
         JetChangeInfo changeInfo = getChangeInfo();
         changeInfo.addParameter(new JetParameterInfo(-1, "s", KotlinBuiltIns.getInstance().getStringType(), null, "\"abc\"", null, null));
-        changeInfo.addParameter(new JetParameterInfo(-1, "o", KotlinBuiltIns.getInstance().getNullableAnyType(), null, "\"def\"", null, null));
+        changeInfo.addParameter(new JetParameterInfo(-1, "o", KotlinBuiltIns.getInstance().getNullableAnyType(), null, "\"def\"", null,
+                                                     null));
         doTest(changeInfo);
     }