# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@fb.com>
# Date 2015-09-24 08:04:58
# Node ID ec4f3755d997c190bf16c6603e986192f687b8bc
# Parent  d9537ce64f3af401b5cfafa1369ed93831c3b10d

templater: remove a mutable default argument

Mutable default arguments are know to the state of California to cause bugs.

diff --git a/mercurial/templater.py b/mercurial/templater.py
--- a/mercurial/templater.py
+++ b/mercurial/templater.py
@@ -792,8 +792,10 @@ class engine(object):
     filter uses function to transform value. syntax is
     {key|filter1|filter2|...}.'''
 
-    def __init__(self, loader, filters={}, defaults={}):
+    def __init__(self, loader, filters=None, defaults={}):
         self._loader = loader
+        if filters is None:
+            filters = {}
         self._filters = filters
         self._defaults = defaults
         self._cache = {}