From d8dc56b03156e70c129a4490ed62a770da6d19d4 Mon Sep 17 00:00:00 2001
From: Brian Gough <bjg@network-theory.co.uk>
Date: Mon, 9 Feb 2015 16:53:05 +0000
Subject: [PATCH] don't try to getLastCompressedUpdates from packs

---
 services/track-changes/app/coffee/MongoManager.coffee | 1 +
 1 file changed, 1 insertion(+)

diff --git a/services/track-changes/app/coffee/MongoManager.coffee b/services/track-changes/app/coffee/MongoManager.coffee
index efcefe9286..9ca6e1ff35 100644
--- a/services/track-changes/app/coffee/MongoManager.coffee
+++ b/services/track-changes/app/coffee/MongoManager.coffee
@@ -11,6 +11,7 @@ module.exports = MongoManager =
 			.limit(1)
 			.toArray (error, compressedUpdates) ->
 				return callback(error) if error?
+				return callback null, null if compressedUpdates[0]?.pack? # cannot pop from a pack
 				return callback null, compressedUpdates[0] or null
 
 	# only used in this module