From cf7f94a55963206d2e1a6ff572821030c7855a18 Mon Sep 17 00:00:00 2001
From: Nikolay Krasko <nikolay.krasko@jetbrains.com>
Date: Thu, 15 Oct 2015 19:05:40 +0300
Subject: [PATCH] Process request for searching class with empty qualified name
 without errors

---
 .../kotlin/cli/jvm/compiler/CliLightClassGenerationSupport.kt | 2 ++
 .../src/org/jetbrains/kotlin/asJava/JavaElementFinder.java    | 2 ++
 compiler/testData/asJava/findClasses/EmptyQualifiedName.kt    | 0
 .../org/jetbrains/kotlin/asJava/JavaElementFinderTest.java    | 4 ++++
 4 files changed, 8 insertions(+)
 create mode 100644 compiler/testData/asJava/findClasses/EmptyQualifiedName.kt

diff --git a/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/CliLightClassGenerationSupport.kt b/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/CliLightClassGenerationSupport.kt
index ddaefebeb96..2d485cabe7b 100644
--- a/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/CliLightClassGenerationSupport.kt
+++ b/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/CliLightClassGenerationSupport.kt
@@ -166,6 +166,8 @@ public class CliLightClassGenerationSupport(project: Project) : LightClassGenera
     }
 
     override fun findFilesForFacade(facadeFqName: FqName, scope: GlobalSearchScope): Collection<JetFile> {
+        if (facadeFqName.isRoot) return emptyList()
+
         return PackagePartClassUtils.getFilesWithCallables(findFilesForPackage(facadeFqName.parent(), scope)).filter {
             JvmFileClassUtil.getFileClassInfoNoResolve(it).facadeClassFqName == facadeFqName
         }
diff --git a/compiler/light-classes/src/org/jetbrains/kotlin/asJava/JavaElementFinder.java b/compiler/light-classes/src/org/jetbrains/kotlin/asJava/JavaElementFinder.java
index fb4566600db..ac9157e04d2 100644
--- a/compiler/light-classes/src/org/jetbrains/kotlin/asJava/JavaElementFinder.java
+++ b/compiler/light-classes/src/org/jetbrains/kotlin/asJava/JavaElementFinder.java
@@ -146,6 +146,8 @@ public class JavaElementFinder extends PsiElementFinder implements KotlinFinderM
     }
 
     private void findInterfaceDefaultImpls(FqName qualifiedName, GlobalSearchScope scope, List<PsiClass> answer) {
+        if (qualifiedName.isRoot()) return;
+
         if (!qualifiedName.shortName().asString().equals(JvmAbi.DEFAULT_IMPLS_CLASS_NAME)) return;
 
         for (JetClassOrObject classOrObject : lightClassGenerationSupport.findClassOrObjectDeclarations(qualifiedName.parent(), scope)) {
diff --git a/compiler/testData/asJava/findClasses/EmptyQualifiedName.kt b/compiler/testData/asJava/findClasses/EmptyQualifiedName.kt
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/compiler/tests/org/jetbrains/kotlin/asJava/JavaElementFinderTest.java b/compiler/tests/org/jetbrains/kotlin/asJava/JavaElementFinderTest.java
index 66ef2c0cd0a..60e3ad0bb4d 100644
--- a/compiler/tests/org/jetbrains/kotlin/asJava/JavaElementFinderTest.java
+++ b/compiler/tests/org/jetbrains/kotlin/asJava/JavaElementFinderTest.java
@@ -47,6 +47,10 @@ public class JavaElementFinderTest extends KotlinAsJavaTestBase {
         // TODO: assertClass("Direction.WEST.Some");
     }
 
+    public void testEmptyQualifiedName() {
+        assertNoClass("");
+    }
+
     private void assertClass(String qualifiedName) {
         PsiClass psiClass = finder.findClass(qualifiedName, GlobalSearchScope.allScope(getProject()));
         assertNotNull(String.format("Class with fqn='%s' wasn't found.", qualifiedName), psiClass);