From afc26d1db0433b1703e04375e8279893e344be6d Mon Sep 17 00:00:00 2001
From: Stewart Allen <stewart@neuron.com>
Date: Wed, 8 Jul 2020 14:49:04 -0400
Subject: [PATCH] safety check on gcode array templating

---
 src/mode/fdm/driver.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/mode/fdm/driver.js b/src/mode/fdm/driver.js
index a46ca417..28c4f11b 100644
--- a/src/mode/fdm/driver.js
+++ b/src/mode/fdm/driver.js
@@ -1001,10 +1001,14 @@
         }
 
         function appendAll(arr) {
+            if (!arr) return;
+            if (!Array.isArray(arr)) arr = [ arr ];
             arr.forEach(function(line) { append(line) });
         }
 
         function appendAllSub(arr) {
+            if (!arr) return;
+            if (!Array.isArray(arr)) arr = [ arr ];
             arr.forEach(function(line) { appendSub(line) });
         }