diff --git a/idea/src/org/jetbrains/jet/plugin/highlighter/DeclarationHintSupport.java b/idea/src/org/jetbrains/jet/plugin/highlighter/DeclarationHintSupport.java
index b026f210505..8d8fc0a2e69 100644
--- a/idea/src/org/jetbrains/jet/plugin/highlighter/DeclarationHintSupport.java
+++ b/idea/src/org/jetbrains/jet/plugin/highlighter/DeclarationHintSupport.java
@@ -43,6 +43,7 @@ import org.jetbrains.jet.lang.psi.JetFile;
 import org.jetbrains.jet.lang.psi.JetNamedDeclaration;
 import org.jetbrains.jet.lang.resolve.BindingContext;
 import org.jetbrains.jet.plugin.JetLanguage;
+import org.jetbrains.jet.plugin.JetPluginUtil;
 import org.jetbrains.jet.plugin.project.WholeProjectAnalyzerFacade;
 import org.jetbrains.jet.plugin.util.LongRunningReadTask;
 import org.jetbrains.jet.renderer.DescriptorRenderer;
@@ -87,7 +88,7 @@ public class DeclarationHintSupport extends AbstractProjectComponent {
 
             Editor editor = e.getEditor();
             PsiFile psiFile = PsiDocumentManager.getInstance(myProject).getPsiFile(editor.getDocument());
-            if (psiFile == null || psiFile.getLanguage() != JetLanguage.INSTANCE) {
+            if (psiFile == null || psiFile.getLanguage() != JetLanguage.INSTANCE || !JetPluginUtil.isInSourceContent(psiFile)) {
                 return;
             }