From f965037fb44184957d9bc20dc3efb1ce1adee6a9 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Mon, 17 Jan 2011 12:22:30 -0700
Subject: [PATCH] MOBI Output: Fix bug that could cause a link pointing to the
 start of a section to go to a point later in the section is the section
 contained an empty id attribute

---
 src/calibre/ebooks/mobi/writer.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/calibre/ebooks/mobi/writer.py b/src/calibre/ebooks/mobi/writer.py
index cd6674c2e2..ed102ecc80 100644
--- a/src/calibre/ebooks/mobi/writer.py
+++ b/src/calibre/ebooks/mobi/writer.py
@@ -251,7 +251,7 @@ class Serializer(object):
         tag = prefixname(elem.tag, nsrmap)
         # Previous layers take care of @name
         id = elem.attrib.pop('id', None)
-        if id is not None:
+        if id:
             href = '#'.join((item.href, id))
             offset = self.anchor_offset or buffer.tell()
             self.id_offsets[urlnormalize(href)] = offset