add unit tests for Role.delete

+# -*- coding: utf-8 -*-
+# Copyright (c) 2015 Mitch Garnaat http://garnaat.org/
+#
+# Licensed under the Apache License, Version 2.0 (the "License"). You
+# may not use this file except in compliance with the License. A copy of
+# the License is located at
+#
+# http://aws.amazon.com/apache2.0/
+#
+# or in the "license" file accompanying this file. This file is
+# distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF
+# ANY KIND, either express or implied. See the License for the specific
+# language governing permissions and limitations under the License.
+
+import unittest
+import random
+import string
+from mock import Mock, call
+
+from kappa.role import Role
+
+
+def randomword(length):
+    return ''.join(random.choice(string.lowercase) for i in range(length))
+
+
+class TestRole(unittest.TestCase):
+
+    def setUp(self):
+        self.iam_client = Mock()
+        policy = type('Policy', (object,), {
+            'arn': None
+        })
+        self.context = type('Context', (object,), {
+            'name': randomword(10),
+            'environment': randomword(10),
+            'policy': policy
+        })
+        self.role_record = {
+            'RoleName': '%s_%s' % (self.context.name,
+                                   self.context.environment),
+            'Arn': randomword(10)
+        }
+        self.role = Role(self.context, None, iam_client=self.iam_client)
+
+    def _expect_get_role(self):
+        get_role_resp = {'Role': self.role_record}
+        self.iam_client.configure_mock(**{
+            'call.return_value': get_role_resp
+        })
+        return get_role_resp
+
+    def test_delete_no_ops_if_role_not_found(self):
+        self.iam_client.configure_mock(**{
+            'call.return_value': None
+        })
+        self.assertEquals(None, self.role.delete())
+        self.assertEquals(1, self.iam_client.call.call_count)
+
+    def test_delete_when_role_exists(self):
+        get_role_resp = self._expect_get_role()
+        self.assertEquals(get_role_resp, self.role.delete())
+        self.iam_client.call.assert_has_calls([call('get_role',
+                                                    RoleName=self.role.name),
+                                               call('delete_role',
+                                                    RoleName=self.role.name)])
+
+    def test_delete_policy_when_context_arn_exists(self):
+        self.context.policy.arn = randomword(10)
+        get_role_resp = self._expect_get_role()
+        self.assertEquals(get_role_resp, self.role.delete())
+        calls = [call('get_role',
+                      RoleName=self.role.name),
+                 call('detach_role_policy',
+                      RoleName=self.role.name,
+                      PolicyArn=self.context.policy.arn),
+                 call('delete_role',
+                      RoleName=self.role.name)]
+        self.iam_client.call.assert_has_calls(calls)