From 9528f4a95bdac2b6b2fb84eaeb6275b4f332e165 Mon Sep 17 00:00:00 2001
From: Deyuan Deng <Deyuan.Deng@gmail.com>
Date: Mon, 8 Jul 2013 23:17:06 -0700
Subject: [PATCH] when open document, check if provider is nil

---
 frontend/document/document.lua | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/frontend/document/document.lua b/frontend/document/document.lua
index d12a057da..917124ef7 100644
--- a/frontend/document/document.lua
+++ b/frontend/document/document.lua
@@ -22,7 +22,10 @@ function DocumentRegistry:getProvider(file)
 end
 
 function DocumentRegistry:openDocument(file)
-	return self:getProvider(file):new{file = file}
+    local provider = self:getProvider(file)
+    if provider ~= nil then
+        return provider:new{file = file}
+    end
 end