From 581ac31deec2f6e8c050db701a01722d84d727eb Mon Sep 17 00:00:00 2001
From: Roman Shevchenko <roman.shevchenko@jetbrains.com>
Date: Thu, 11 Nov 2010 19:45:20 +0300
Subject: [PATCH] EA-23185 (diagnostic added)

---
 .../src/com/intellij/psi/impl/source/text/ASTDiffBuilder.java    | 1 +
 1 file changed, 1 insertion(+)

diff --git a/platform/lang-impl/src/com/intellij/psi/impl/source/text/ASTDiffBuilder.java b/platform/lang-impl/src/com/intellij/psi/impl/source/text/ASTDiffBuilder.java
index ba02345507a2..24c63ca26335 100644
--- a/platform/lang-impl/src/com/intellij/psi/impl/source/text/ASTDiffBuilder.java
+++ b/platform/lang-impl/src/com/intellij/psi/impl/source/text/ASTDiffBuilder.java
@@ -59,6 +59,7 @@ public class ASTDiffBuilder implements DiffTreeChangeBuilder<ASTNode, ASTNode> {
     }
     else {
       final ASTNode parent = oldNode.getTreeParent();
+      assert parent != null : "old:" + oldNode + " new:" + newNode;
 
       TreeUtil.ensureParsed(oldNode);