From c8d37dd192f656be970515919ae8208294a59d96 Mon Sep 17 00:00:00 2001
From: Wu Cheng-Han <jacky_cute0808@hotmail.com>
Date: Mon, 19 Dec 2016 16:53:54 +0800
Subject: [PATCH] Update to handle graphviz output empty graph

---
 public/js/extra.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/public/js/extra.js b/public/js/extra.js
index 6143352..0f67f8f 100644
--- a/public/js/extra.js
+++ b/public/js/extra.js
@@ -343,6 +343,7 @@ function finishView(view) {
             var $ele = $(value).parent().parent();
 
             var graphviz = Viz($value.text());
+            if (!graphviz) throw Error('viz.js output empty graph');
             $value.html(graphviz);
 
             $ele.addClass('graphviz');