Ryanpineo fix ipaddr netmask with 32 cidr (#23506)

* Fix bug in ipaddr netmask filter when cidr is 32

* Add requirement on netaddr to the units.txt file

test/runner/requirements/units.txt

@@ -13,3 +13,4 @@ python-memcached
 pyyaml
 redis
 unittest2 ; python_version < '2.7'
+netaddr

test/units/plugins/filter/test_ipaddr.py

@@ -0,0 +1,35 @@
+# 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
+
+from ansible.compat.tests import unittest
+from ansible.plugins.filter.ipaddr import ipaddr, _netmask_query
+
+
+class TestNetmask(unittest.TestCase):
+    def test_whole_octets(self):
+        address = '1.1.1.1/24'
+        self.assertEqual(ipaddr(address, 'netmask'), '255.255.255.0')
+
+    def test_partial_octet(self):
+        address = '1.1.1.1/25'
+        self.assertEqual(ipaddr(address, 'netmask'), '255.255.255.128')
+
+    def test_32_cidr(self):
+        address = '1.12.1.34/32'
+        self.assertEqual(ipaddr(address, 'netmask'), '255.255.255.255')