From 189c0f360e4d6c72406418154774367d888eea79 Mon Sep 17 00:00:00 2001
From: Koen Kanters <koenkanters94@gmail.com>
Date: Sat, 2 Feb 2019 02:14:31 +0100
Subject: [PATCH] Guard callbacks.

---
 lib/zigbee.js | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/lib/zigbee.js b/lib/zigbee.js
index 823981afe..f9148c4a1 100644
--- a/lib/zigbee.js
+++ b/lib/zigbee.js
@@ -248,7 +248,9 @@ class Zigbee {
                         `failed with error ${error}`);
                 }
 
-                callback(error, rsp);
+                if (callback) {
+                    callback(error, rsp);
+                }
             };
 
             if (cmdType === 'functional' && entity.functional) {
@@ -276,7 +278,9 @@ class Zigbee {
                         logger.debug(`Successfully pinged ${ieeeAddr}`);
                     }
 
-                    cb(error);
+                    if (cb) {
+                        cb(error);
+                    }
                 });
 
                 setTimeout(() => queueCallback(), delay);