diff -r 21f129354dd0 -r 5b2241e84982 mercurial/formatter.py
--- a/mercurial/formatter.py	Wed Apr 05 22:25:36 2017 +0900
+++ b/mercurial/formatter.py	Wed Apr 05 22:28:09 2017 +0900
@@ -321,8 +321,8 @@
         data = util.sortdict(_iteritems(data))
         def f():
             yield _plainconverter.formatdict(data, key, value, fmt, sep)
-        return templatekw._hybrid(f(), data, lambda k: {key: k, value: data[k]},
-                                  lambda d: fmt % (d[key], d[value]))
+        return templatekw.hybriddict(data, key=key, value=value, fmt=fmt,
+                                     gen=f())
     @staticmethod
     def formatlist(data, name, fmt, sep):
         '''build object that can be evaluated as either plain string or list'''