From 7dec43d9d847481ad93fca498fd970b3a4a14b11 Mon Sep 17 00:00:00 2001
From: Bo Du <bo@capsule8.com>
Date: Fri, 15 Sep 2017 00:10:25 -0400
Subject: [PATCH] Handle case where 'extendee' is undefined.

---
 ext/descriptor/index.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/ext/descriptor/index.js b/ext/descriptor/index.js
index b33db3b98..6f230caaa 100644
--- a/ext/descriptor/index.js
+++ b/ext/descriptor/index.js
@@ -400,12 +400,16 @@ Field.fromDescriptor = function fromDescriptor(descriptor, syntax) {
         default: throw Error("illegal label: " + descriptor.label);
     }
 
+	var extendee = descriptor.extendee;
+	if (descriptor.extendee !== undefined) {
+		extendee = extendee.length ? extendee : undefined;
+	}
     var field = new Field(
         descriptor.name.length ? descriptor.name : "field" + descriptor.number,
         descriptor.number,
         fieldType,
         fieldRule,
-        descriptor.extendee.length ? descriptor.extendee : undefined
+        extendee
     );
 
     field.options = fromDescriptorOptions(descriptor.options, exports.FieldOptions);