From 7eb0f42560d58254d596270f89b9686b5559fdbd Mon Sep 17 00:00:00 2001
From: Cyrus Najmabadi <cyrusn@microsoft.com>
Date: Fri, 12 Dec 2014 00:48:08 -0800
Subject: [PATCH] Add assert.

---
 src/compiler/parser.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index ec78a807448..ac014fea9e8 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -490,6 +490,9 @@ module ts {
                 // called with 'isListElement', we don't want to redo the work when parseListElement
                 // is called immediately after.
                 lastQueriedPosition = position;
+
+                // Either we don'd have a node, or we have a node at the position being asked for.
+                Debug.assert(!current || current.pos === position);
                 return <IncrementalNode>current;
             }
         };