Supported renaming of default object. Named only objects are supported

yet.

compiler/light-classes/src/org/jetbrains/kotlin/asJava/KotlinLightField.java

@@ -174,4 +174,12 @@ public abstract class KotlinLightField<T extends JetDeclaration, D extends PsiFi
     public Language getLanguage() {
         return JetLanguage.INSTANCE;
     }
+
+    @Override
+    public boolean isEquivalentTo(PsiElement another) {
+        if (another instanceof KotlinLightField && origin.isEquivalentTo(((KotlinLightField) another).getOrigin())) {
+            return true;
+        }
+        return super.isEquivalentTo(another);
+    }
 }

compiler/light-classes/src/org/jetbrains/kotlin/asJava/LightClassUtil.java

@@ -149,6 +149,20 @@ public class LightClassUtil {
         return getPsiMethodWrapper(accessor);
     }
 
+    @Nullable
+    public static PsiField getLightFieldForDefaultObject(@NotNull JetClassOrObject defaultObject) {
+        PsiClass outerPsiClass = getWrappingClass(defaultObject);
+        if (outerPsiClass != null) {
+            for (PsiField fieldOfParent : outerPsiClass.getFields()) {
+                if (((KotlinLightElement<?, ?>) fieldOfParent).getOrigin() == defaultObject &&
+                    fieldOfParent.getName().equals(defaultObject.getName())) { // TODO this check is relevant while light class has deprecated OBJECT$ field
+                    return fieldOfParent;
+                }
+            }
+        }
+        return null;
+    }
+
     @NotNull
     public static PropertyAccessorsPsiMethods getLightClassPropertyMethods(@NotNull JetProperty property) {
         JetPropertyAccessor getter = property.getGetter();

idea/idea-analysis/src/org/jetbrains/kotlin/idea/search/ideaExtensions/KotlinReferencesSearcher.java

@@ -25,9 +25,7 @@ import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.util.Processor;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
-import org.jetbrains.kotlin.asJava.AsJavaPackage;
-import org.jetbrains.kotlin.asJava.KotlinLightMethod;
-import org.jetbrains.kotlin.asJava.LightClassUtil;
+import org.jetbrains.kotlin.asJava.*;
 import org.jetbrains.kotlin.idea.search.usagesSearch.*;
 import org.jetbrains.kotlin.idea.util.ProjectRootsUtil;
 import org.jetbrains.kotlin.psi.*;
@@ -46,6 +44,18 @@ public class KotlinReferencesSearcher extends QueryExecutorBase<PsiReference, Re
             });
             if (lightClass != null) {
                 searchNamedElement(queryParameters, lightClass, className);
+
+                if (element instanceof JetObjectDeclaration && ((JetObjectDeclaration) element).isDefault()) {
+                    PsiField fieldForDefaultObject = ApplicationManager.getApplication().runReadAction(new Computable<PsiField>() {
+                        @Override
+                        public PsiField compute() {
+                            return LightClassUtil.getLightFieldForDefaultObject(element);
+                        }
+                    });
+                    if (fieldForDefaultObject != null) {
+                        searchNamedElement(queryParameters, fieldForDefaultObject);
+                    }
+                }
             }
         }
     }

idea/testData/refactoring/rename/defaultObject/after/JavaUsage.java

@@ -0,0 +1,8 @@
+class JavaUsage {
+    public static void main(String[] args) {
+        System.out.println(Foo.CONST);
+        Foo.s();
+        Foo.Baz.f();
+        Foo foo = new Foo(); // not usage of default object
+    }
+}

idea/testData/refactoring/rename/defaultObject/after/toBeRenamed.kt

@@ -0,0 +1,11 @@
+class Foo {
+    default object Baz {
+        fun f() {
+        }
+
+        platformStatic fun s() {
+        }
+
+        val CONST = 42
+    }
+}

idea/testData/refactoring/rename/defaultObject/after/usage.kt

@@ -0,0 +1,8 @@
+fun main(args: Array<String>) {
+    // class object usages
+    Foo.f()
+    val x = Foo
+
+    Foo.Baz.f()
+    val xx = Foo.Baz
+}

idea/testData/refactoring/rename/defaultObject/before/javaUsage.java

@@ -0,0 +1,8 @@
+class JavaUsage {
+    public static void main(String[] args) {
+        System.out.println(Foo.CONST);
+        Foo.s();
+        Foo.Bar.f();
+        Foo foo = new Foo(); // not usage of default object
+    }
+}

idea/testData/refactoring/rename/defaultObject/before/toBeRenamed.kt

@@ -0,0 +1,11 @@
+class Foo {
+    default object Bar {
+        fun f() {
+        }
+
+        platformStatic fun s() {
+        }
+
+        val CONST = 42
+    }
+}

idea/testData/refactoring/rename/defaultObject/before/usage.kt

@@ -0,0 +1,8 @@
+fun main(args: Array<String>) {
+    // class object usages
+    Foo.f()
+    val x = Foo
+
+    Foo.Bar.f()
+    val xx = Foo.Bar
+}

idea/testData/refactoring/rename/defaultObject/defaultObject.test

@@ -0,0 +1,7 @@
+{
+  "type": "KOTLIN_CLASS",
+  "classId": "/Foo.Bar",
+  "oldName": "Bar",
+  "newName": "Baz",
+  "mainFile": "toBeRenamed.kt"
+}

idea/tests/org/jetbrains/kotlin/idea/refactoring/rename/RenameTestGenerated.java

@@ -36,6 +36,12 @@ public class RenameTestGenerated extends AbstractRenameTest {
         JetTestUtils.assertAllTestsPresentInSingleGeneratedClass(this.getClass(), new File("idea/testData/refactoring/rename"), Pattern.compile("^(.+)\\.test$"));
     }
 
+    @TestMetadata("defaultObject/defaultObject.test")
+    public void testDefaultObject_DefaultObject() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/refactoring/rename/defaultObject/defaultObject.test");
+        doTest(fileName);
+    }
+
     @TestMetadata("renameCompareTo/compareTo.test")
     public void testRenameCompareTo_CompareTo() throws Exception {
         String fileName = JetTestUtils.navigationMetadata("idea/testData/refactoring/rename/renameCompareTo/compareTo.test");