Break apart a looped dependency to show a warning when parsing playbooks

Display a warning when a dict key is overwritten by pyyaml
Fixes #12888

lib/ansible/parsing/quoting.py

@@ -0,0 +1,30 @@
+# (c) 2014 James Cammarata, <jcammarata@ansible.com>
+#
+# This file is part of Ansible
+#
+# Ansible is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# Ansible is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
+
+# Make coding more python3-ish
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+
+def is_quoted(data):
+    return len(data) > 1 and data[0] == data[-1] and data[0] in ('"', "'") and data[-2] != '\\'
+
+def unquote(data):
+    ''' removes first and last quotes from a string, if the string starts and ends with the same quotes '''
+    if is_quoted(data):
+        return data[1:-1]
+    return data