From e9a2c24280e21e1a1ca3db06771c4458d73b57b7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Javier=20Mendiara=20Ca=C3=B1ardo?=
 <javier.mendiaracanardo@telefonica.com>
Date: Tue, 11 Oct 2016 17:23:34 +0200
Subject: [PATCH] [[FIX]] Check stack in Error instances

---
 lib/index.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/index.js b/lib/index.js
index a2ad9c5..fc7023f 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -139,7 +139,7 @@ function formatObject(error) {
 }
 
 function formatStack(error) {
-  if (error instanceof Error) {
+  if (error instanceof Error && error.stack != null) {
     var stack = error.stack;
     return stack.substring(stack.indexOf('\n') + 1);
   }