--- a/mercurial/patch.py	Sat Dec 31 15:41:57 2016 -0600
+++ b/mercurial/patch.py	Mon Jan 09 10:59:45 2017 -0800
@@ -2343,6 +2343,7 @@
                     ('old', 'diff.extended'),
                     ('new', 'diff.extended'),
                     ('deleted', 'diff.extended'),
+                    ('index', 'diff.extended'),
                     ('---', 'diff.file_a'),
                     ('+++', 'diff.file_b')]
     textprefixes = [('@', 'diff.hunk'),