From b80be0b847fc216498643429e3bcc7a685bc454c Mon Sep 17 00:00:00 2001
From: Jeff DeFond <jeff.defond@cleardata.com>
Date: Fri, 13 Jan 2017 12:28:45 -0800
Subject: [PATCH] Add check to see if v.onConfigChange is nil before calling

---
 viper.go | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/viper.go b/viper.go
index 2603c78..1bc46f5 100644
--- a/viper.go
+++ b/viper.go
@@ -262,7 +262,9 @@ func (v *Viper) WatchConfig() {
 							if err != nil {
 								log.Println("error:", err)
 							}
-							v.onConfigChange(event)
+							if v.onConfigChange != nil {
+								v.onConfigChange(event)
+							}
 						}
 					}
 				case err := <-watcher.Errors: