From 93df8afa5415b807d14e5d28aad65bf8a12c990f Mon Sep 17 00:00:00 2001
From: olegp <o.pecherin@alpinadigital.ru>
Date: Thu, 6 Sep 2018 17:03:51 +0300
Subject: [PATCH] fix EpubCFI(null) Uncaught TypeError: Cannot read property
 'startContainer' of null

---
 src/epubcfi.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/epubcfi.js b/src/epubcfi.js
index 4d045b7..4723a72 100644
--- a/src/epubcfi.js
+++ b/src/epubcfi.js
@@ -77,11 +77,11 @@ class EpubCFI {
 		if (this.isCfiString(cfi)) {
 			return "string";
 		// Is a range object
-		} else if (typeof cfi === "object" && (type(cfi) === "Range" || typeof(cfi.startContainer) != "undefined")){
+		} else if (cfi && typeof cfi === "object" && (type(cfi) === "Range" || typeof(cfi.startContainer) != "undefined")){
 			return "range";
-		} else if (typeof cfi === "object" && typeof(cfi.nodeType) != "undefined" ){ // || typeof cfi === "function"
+		} else if (cfi && typeof cfi === "object" && typeof(cfi.nodeType) != "undefined" ){ // || typeof cfi === "function"
 			return "node";
-		} else if (typeof cfi === "object" && cfi instanceof EpubCFI){
+		} else if (cfi && typeof cfi === "object" && cfi instanceof EpubCFI){
 			return "EpubCFI";
 		} else {
 			return false;