Fix delegation-find command --group handling

A wrong way of handling --group DN object caused Internal Error
for this command. Fix that and also provide unit tests to avoid
another regression.

https://fedorahosted.org/freeipa/ticket/3311

ipalib/plugins/aci.py

@@ -801,7 +801,7 @@ class aci_find(crud.Search):
                 groupdn = a.bindrule['expression']
                 groupdn = DN(groupdn.replace('ldap:///',''))
                 try:
-                    cn = groupdn[0]['cn'].value
+                    cn = groupdn[0]['cn']
                 except (IndexError, KeyError):
                     cn = None
                 if cn is None or cn != kw['group']:

tests/test_xmlrpc/test_delegation_plugin.py

@@ -177,6 +177,46 @@ class test_delegation(Declarative):
         ),
 
 
+        dict(
+            desc='Search for %r using --group filter' % delegation1,
+            command=('delegation_find', [delegation1], {'group': u'editors'}),
+            expected=dict(
+                count=1,
+                truncated=False,
+                summary=u'1 delegation matched',
+                result=[
+                    {
+                    'attrs': [u'street', u'c', u'l', u'st', u'postalcode'],
+                    'permissions': [u'write'],
+                    'aciname': delegation1,
+                    'group': u'editors',
+                    'memberof': member1,
+                    },
+                ],
+            ),
+        ),
+
+
+        dict(
+            desc='Search for %r using --membergroup filter' % delegation1,
+            command=('delegation_find', [delegation1], {'memberof': member1}),
+            expected=dict(
+                count=1,
+                truncated=False,
+                summary=u'1 delegation matched',
+                result=[
+                    {
+                    'attrs': [u'street', u'c', u'l', u'st', u'postalcode'],
+                    'permissions': [u'write'],
+                    'aciname': delegation1,
+                    'group': u'editors',
+                    'memberof': member1,
+                    },
+                ],
+            ),
+        ),
+
+
         dict(
             desc='Search for %r with --pkey-only' % delegation1,
             command=('delegation_find', [delegation1], {'pkey_only' : True}),