From 36c18d1d3bdc53efb26cc6c356fe2b361585fd1b Mon Sep 17 00:00:00 2001
From: peter <peter.gromov@jetbrains.com>
Date: Tue, 6 Jul 2010 19:42:37 +0100
Subject: [PATCH] diagnostics for the NPE when cloning a PsiFile for completion

---
 .../src/com/intellij/psi/impl/source/PsiFileImpl.java          | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/platform/lang-impl/src/com/intellij/psi/impl/source/PsiFileImpl.java b/platform/lang-impl/src/com/intellij/psi/impl/source/PsiFileImpl.java
index ca5790dbb3e1..c4a935a73757 100644
--- a/platform/lang-impl/src/com/intellij/psi/impl/source/PsiFileImpl.java
+++ b/platform/lang-impl/src/com/intellij/psi/impl/source/PsiFileImpl.java
@@ -385,6 +385,9 @@ public abstract class PsiFileImpl extends ElementBase implements PsiFileEx, PsiF
   protected PsiFileImpl clone() {
     FileViewProvider provider = getViewProvider().clone();
     final Language language = getLanguage();
+    if (provider == null) {
+      throw new AssertionError("Unable to clone the view provider: " + getViewProvider() + "; " + language);
+    }
     PsiFileImpl clone = (PsiFileImpl)provider.getPsi(language);
     assert clone != null:"Cannot find psi file with language:"+language + " from viewprovider:"+provider+" virtual file:"+getVirtualFile();