From 6abbf2221e3928c8145cc641c581e3919842d9eb Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Wed, 16 Oct 2019 18:26:08 +0530
Subject: [PATCH] Viewer: Fix an error when processing a CFI with an invalid
 text offset. Fixes #1848320 [E-book viewer -  Error: Unhandled
 error](https://bugs.launchpad.net/calibre/+bug/1848320)

---
 src/pyj/read_book/cfi.pyj | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pyj/read_book/cfi.pyj b/src/pyj/read_book/cfi.pyj
index 221d62acea..513ca6ad37 100644
--- a/src/pyj/read_book/cfi.pyj
+++ b/src/pyj/read_book/cfi.pyj
@@ -468,7 +468,7 @@ def point(cfi, doc):  # {{{
             try_list = [{'start':0, 'end':0, 'a':0.5}, {'start':-1, 'end':0, 'a':0}, {'start':0, 'end':1, 'a':1}]
         a = None
         rects = None
-        node_len = node.nodeValue.length
+        node_len = node.nodeValue.length if node.nodeValue else 0
         offset = r.offset
         for v'var i = 0; i < 2; i++':
             # Try reducing the offset by 1 if we get no match as if it refers to the position after the