diff --git a/idea/src/org/jetbrains/jet/plugin/completion/ToFromOriginalFileMapper.kt b/idea/src/org/jetbrains/jet/plugin/completion/ToFromOriginalFileMapper.kt
index 77f488ec647..a46000c81e6 100644
--- a/idea/src/org/jetbrains/jet/plugin/completion/ToFromOriginalFileMapper.kt
+++ b/idea/src/org/jetbrains/jet/plugin/completion/ToFromOriginalFileMapper.kt
@@ -59,11 +59,13 @@ class ToFromOriginalFileMapper(
     }
 
     public fun toOriginalFile(declaration: JetDeclaration): JetDeclaration? {
+        if (declaration.getContainingFile() != syntheticFile) return declaration
         val offset = toOriginalFile(declaration.getTextRange().getStartOffset()) ?: return null
         return PsiTreeUtil.findElementOfClassAtOffset(originalFile, offset, javaClass<JetDeclaration>(), true)
     }
 
     public fun toSyntheticFile(declaration: JetDeclaration): JetDeclaration? {
+        if (declaration.getContainingFile() != originalFile) return declaration
         val offset = toSyntheticFile(declaration.getTextRange().getStartOffset()) ?: return null
         return PsiTreeUtil.findElementOfClassAtOffset(syntheticFile, offset, javaClass<JetDeclaration>(), true)
     }
diff --git a/idea/src/org/jetbrains/jet/plugin/completion/smart/TypeInstantiationItems.kt b/idea/src/org/jetbrains/jet/plugin/completion/smart/TypeInstantiationItems.kt
index f921808e4a4..4c0dd3e4dde 100644
--- a/idea/src/org/jetbrains/jet/plugin/completion/smart/TypeInstantiationItems.kt
+++ b/idea/src/org/jetbrains/jet/plugin/completion/smart/TypeInstantiationItems.kt
@@ -114,8 +114,8 @@ class TypeInstantiationItems(
             descriptor: ClassDescriptor, kotlinClassDescriptor: ClassDescriptor, typeArgs: List<TypeProjection>, tail: Tail?
     ) {
         val _declaration = DescriptorToSourceUtils.descriptorToDeclaration(descriptor) ?: return
-        val declaration = if (_declaration.getContainingFile() == toFromOriginalFileMapper.syntheticFile)
-            toFromOriginalFileMapper.toOriginalFile(_declaration as JetDeclaration) ?: return
+        val declaration = if (_declaration is JetDeclaration)
+            toFromOriginalFileMapper.toOriginalFile(_declaration) ?: return
         else
             _declaration
 
@@ -281,10 +281,7 @@ class TypeInstantiationItems(
             for (inheritor in ClassInheritorsSearch.search(parameters)) {
                 val descriptor = if (inheritor is KotlinLightClass) {
                     val origin = inheritor.origin ?: continue
-                    val declaration = if (origin.getContainingFile() == toFromOriginalFileMapper.originalFile)
-                        toFromOriginalFileMapper.toSyntheticFile(origin) ?: continue
-                    else
-                        origin
+                    val declaration = toFromOriginalFileMapper.toSyntheticFile(origin) ?: continue
                     resolutionFacade.resolveToDescriptor(declaration)
                 }
                 else {