Move: Do not search/process usages if package is not changed

idea/src/org/jetbrains/kotlin/idea/refactoring/move/changePackage/KotlinChangePackageRefactoring.kt

@@ -42,6 +42,7 @@ public class KotlinChangePackageRefactoring(val file: JetFile) {
         val declarationProcessor = MoveKotlinTopLevelDeclarationsProcessor(
                 project,
                 MoveKotlinTopLevelDeclarationsOptions(
+                        sourceFile = file,
                         elementsToMove = file.getDeclarations().filterIsInstance<JetNamedDeclaration>(),
                         moveTarget = object: KotlinMoveTarget {
                             override val packageWrapper = PackageWrapper(file.getManager(), newFqName.asString())

idea/src/org/jetbrains/kotlin/idea/refactoring/move/moveFilesOrDirectories/MoveKotlinFileHandler.kt

@@ -70,6 +70,7 @@ public class MoveKotlinFileHandler : MoveFileHandler() {
         val declarationMoveProcessor = MoveKotlinTopLevelDeclarationsProcessor(
                 project,
                 MoveKotlinTopLevelDeclarationsOptions(
+                        sourceFile = psiFile,
                         elementsToMove = psiFile.getDeclarations().filterIsInstance<JetNamedDeclaration>(),
                         moveTarget = DeferredJetFileKotlinMoveTarget(project, packageNameInfo.newPackageName) {
                             MoveFilesOrDirectoriesUtil.doMoveFile(psiFile, newParent)

idea/src/org/jetbrains/kotlin/idea/refactoring/move/moveTopLevelDeclarations/MoveKotlinTopLevelDeclarationsProcessor.kt

@@ -80,6 +80,7 @@ trait Mover: (originalElement: JetNamedDeclaration, targetFile: JetFile) -> JetN
 }
 
 public class MoveKotlinTopLevelDeclarationsOptions(
+        val sourceFile: JetFile,
         val elementsToMove: Collection<JetNamedDeclaration>,
         val moveTarget: KotlinMoveTarget,
         val searchInCommentsAndStrings: Boolean = true,
@@ -217,6 +218,9 @@ public class MoveKotlinTopLevelDeclarationsProcessor(
             }
         }
 
+        // No need to find and process usages if package is not changed
+        if (options.sourceFile.getPackageFqName().asString() == newPackageName) return UsageInfo.EMPTY_ARRAY
+
         val usages = collectUsages()
         collectConflictsInUsages(usages)
         collectConflictsInDeclarations()

idea/src/org/jetbrains/kotlin/idea/refactoring/move/moveTopLevelDeclarations/ui/MoveKotlinTopLevelDeclarationsDialog.java

@@ -565,7 +565,7 @@ public class MoveKotlinTopLevelDeclarationsDialog extends RefactoringDialog {
             }
 
             MoveKotlinTopLevelDeclarationsOptions options = new MoveKotlinTopLevelDeclarationsOptions(
-                    elementsToMove, target, isSearchInComments(), isSearchInNonJavaFiles(), true, moveCallback
+                    sourceFile, elementsToMove, target, isSearchInComments(), isSearchInNonJavaFiles(), true, moveCallback
             );
             invokeRefactoring(new MoveKotlinTopLevelDeclarationsProcessor(myProject, options, Mover.Default.INSTANCE$));
         }

idea/tests/org/jetbrains/kotlin/idea/refactoring/move/AbstractJetMoveTest.kt

@@ -253,7 +253,7 @@ enum class MoveAction {
                 JetFileKotlinMoveTarget(PsiManager.getInstance(project).findFile(rootDir.findFileByRelativePath(filePath)!!) as JetFile)
             }
 
-            val options = MoveKotlinTopLevelDeclarationsOptions(listOf(elementToMove), moveTarget)
+            val options = MoveKotlinTopLevelDeclarationsOptions(mainFile as JetFile, listOf(elementToMove), moveTarget)
             MoveKotlinTopLevelDeclarationsProcessor(mainFile.getProject(), options).run()
         }
     },