diff --git a/lib/ansible/playbook/attribute.py b/lib/ansible/playbook/attribute.py index 644b368be60..65b33b300fe 100644 --- a/lib/ansible/playbook/attribute.py +++ b/lib/ansible/playbook/attribute.py @@ -19,7 +19,10 @@ from __future__ import (absolute_import, division, print_function) __metaclass__ = type -from copy import deepcopy +from copy import copy, deepcopy + + +_CONTAINERS = frozenset(('list', 'dict', 'set')) class Attribute: @@ -84,8 +87,17 @@ class Attribute: self.extend = extend self.prepend = prepend - if default is not None and self.isa in ('list', 'dict', 'set'): - self.default = deepcopy(default) + if default is not None and self.isa in _CONTAINERS: + if default: + self.default = deepcopy(default) + else: + # Don't need to deepcopy default if the container is empty + # Note: switch to try: except once Python3 is more widespread + if hasattr(default, 'copy'): + self.default = default.copy() + else: + # list on python2 does not have .copy() + self.default = copy(default) else: self.default = default