--- a/mercurial/commands.py	Wed Apr 05 15:15:06 2017 -0700
+++ b/mercurial/commands.py	Wed Apr 05 15:31:08 2017 -0700
@@ -162,6 +162,7 @@
 diffopts = [
     ('a', 'text', None, _('treat all files as text')),
     ('g', 'git', None, _('use git extended diff format')),
+    ('', 'binary', None, _('generate binary diffs in git mode (default)')),
     ('', 'nodates', None, _('omit dates from diff headers'))
 ]