Merge lp:~matiasb/u1-test-utils/improved-django-patch-settings into lp:u1-test-utils

[Matias Bordese]

Improved django patch_settings to provide start/stop methods.

Improved django patch_settings to provide start/stop methods (taken from SSO).

[lp:~matiasb/u1-test-utils/improved-django-patch-settings]

39. By Matias Bordese on 2013-03-20

Added tests.

[Leo Arias (elopio)]

love it. Thanks!

review: Approve (code review)

[Natalia Bidart (nataliabidart)]

Looks great, but a test is missing: when the setting being patched is not present (ie, the setting should not be set after the test)

review: Needs Fixing

[lp:~matiasb/u1-test-utils/improved-django-patch-settings]

40. By Matias Bordese on 2013-03-20

Added additional test.

[Natalia Bidart (nataliabidart)]

Looks great!

review: Approve

=== modified file 'u1testutils/django.py'
--- u1testutils/django.py	2012-12-04 19:56:54 +0000
+++ u1testutils/django.py	2013-03-20 17:16:24 +0000
@@ -3,7 +3,6 @@
 import re
 import string
 import time
-from contextlib import contextmanager
 
 from django.conf import settings
 from django.test import TestCase
@@ -29,17 +28,37 @@
 
     return old_settings
 
-
-@contextmanager
-def patch_settings(**kwargs):
-    old_settings = switch_settings(**kwargs)
-    try:
-        yield
-    finally:
-        switch_settings(**old_settings)
 # end snippet
 
 
+class patch_settings(object):
+
+    def __init__(self, **kwargs):
+        super(patch_settings, self).__init__()
+        self.marker = object()
+        self.old_settings = {}
+        self.kwargs = kwargs
+
+    def start(self):
+        for setting, new_value in self.kwargs.items():
+            old_value = getattr(settings, setting, self.marker)
+            self.old_settings[setting] = old_value
+            setattr(settings, setting, new_value)
+
+    def stop(self):
+        for setting, old_value in self.old_settings.items():
+            if old_value is self.marker:
+                delattr(settings, setting)
+            else:
+                setattr(settings, setting, old_value)
+
+    def __enter__(self):
+        self.start()
+
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        self.stop()
+
+
 class CsrfMiddlewareEnabledTestCase(TestCase):
     def setUp(self):
         # make sure csrf middleware is enabled

=== added file 'u1testutils/selftests/unit/test_django.py'
--- u1testutils/selftests/unit/test_django.py	1970-01-01 00:00:00 +0000
+++ u1testutils/selftests/unit/test_django.py	2013-03-20 17:16:24 +0000
@@ -0,0 +1,45 @@
+# -*- coding: utf-8 -*-
+
+# Copyright 2013 Canonical Ltd.
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License version 3, as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranties of
+# MERCHANTABILITY, SATISFACTORY QUALITY, or FITNESS FOR A PARTICULAR
+# PURPOSE.  See the GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program.  If not, see <http://www.gnu.org/licenses/
+
+import unittest
+
+from django.conf import settings
+
+from u1testutils.django import patch_settings
+
+
+class PatchSettingsTestCase(unittest.TestCase):
+
+    def test_patch_settings_using_as_context_manager(self):
+        assert not settings.DEBUG
+        with patch_settings(DEBUG=True):
+            self.assertTrue(settings.DEBUG)
+        self.assertFalse(settings.DEBUG)
+
+    def test_patch_settings_start_stop(self):
+        assert not settings.DEBUG
+        p = patch_settings(DEBUG=True)
+        p.start()
+        self.assertTrue(settings.DEBUG)
+        p.stop()
+        self.assertFalse(settings.DEBUG)
+
+    def test_patch_settings_not_available_setting(self):
+        marker = object()
+        assert getattr(settings, 'NOT_AVAILABLE', marker) is marker
+        with patch_settings(NOT_AVAILABLE=True):
+            self.assertTrue(settings.NOT_AVAILABLE)
+        self.assertIs(getattr(settings, 'NOT_AVAILABLE', marker), marker)