From 031049ea9df48a8894e5176bde560b0138a97473 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Wed, 6 Jul 2016 10:29:18 +0530
Subject: [PATCH] DRYer

---
 src/calibre/ebooks/metadata/opf3.py        |  5 +++--
 src/calibre/ebooks/oeb/polish/container.py | 14 +++++---------
 2 files changed, 8 insertions(+), 11 deletions(-)

diff --git a/src/calibre/ebooks/metadata/opf3.py b/src/calibre/ebooks/metadata/opf3.py
index f7879b4c5b..5ccfadf275 100644
--- a/src/calibre/ebooks/metadata/opf3.py
+++ b/src/calibre/ebooks/metadata/opf3.py
@@ -117,12 +117,13 @@ def simple_text(f):
     return wrapper
 
 def items_with_property(root, q, prefixes):
-    q = expand_prefix(q, prefixes)
+    q = expand_prefix(q, prefixes).lower()
     for item in XPath("./opf:manifest/opf:item[@properties]")(root):
-        for prop in (item.get('properties') or '').split():
+        for prop in (item.get('properties') or '').lower().split():
             prop = expand_prefix(prop, prefixes)
             if prop == q:
                 yield item
+                break
 
 # }}}
 
diff --git a/src/calibre/ebooks/oeb/polish/container.py b/src/calibre/ebooks/oeb/polish/container.py
index 9a577c2a7b..d0795f6a67 100644
--- a/src/calibre/ebooks/oeb/polish/container.py
+++ b/src/calibre/ebooks/oeb/polish/container.py
@@ -24,7 +24,7 @@ from calibre.ebooks.chardet import xml_to_unicode
 from calibre.ebooks.conversion.plugins.epub_input import (
     ADOBE_OBFUSCATION, IDPF_OBFUSCATION, decrypt_font_data)
 from calibre.ebooks.conversion.preprocess import HTMLPreProcessor, CSSPreProcessor as cssp
-from calibre.ebooks.metadata.opf3 import read_prefixes, expand_prefix, ensure_prefix, CALIBRE_PREFIX
+from calibre.ebooks.metadata.opf3 import read_prefixes, items_with_property, ensure_prefix, CALIBRE_PREFIX
 from calibre.ebooks.metadata.utils import parse_opf_version
 from calibre.ebooks.mobi import MobiError
 from calibre.ebooks.mobi.reader.headers import MetadataHeader
@@ -614,14 +614,10 @@ class Container(ContainerBase):  # {{{
     def manifest_items_with_property(self, property_name):
         ' All manifest items that have the specified property '
         prefixes = read_prefixes(self.opf)
-        q = expand_prefix(property_name, prefixes).lower()
-        for item in self.opf_xpath('//opf:manifest/opf:item[@href and @properties]'):
-            props = (item.get('properties') or '').lower().split()
-            for p in props:
-                pq = expand_prefix(p, prefixes).lower()
-                if pq == q:
-                    yield self.href_to_name(item.get('href'), self.opf_name)
-                    break
+        for item in items_with_property(self.opf, property_name, prefixes):
+            href = item.get('href')
+            if href:
+                yield self.href_to_name(item.get('href'), self.opf_name)
 
     def manifest_items_of_type(self, predicate):
         ''' The names of all manifest items whose media-type matches predicate.