TestSettingsManager

test.py

# This should be in a global namespace shared across your entire project
from django.conf import settings

NO_SETTING = ('!', None)

class TestSettingsManager(object):
    """
    A class which can modify some Django settings temporarily for a
    test and then revert them to their original values later.
    
    Automatically handles resyncing the DB if INSTALLED_APPS is
    modified.
    """
    def __init__(self):
        self._original_settings = {}

    def syncdb(self):
        loading.cache.loaded = False
        call_command('syncdb', verbosity=0)

    def set(self, **kwargs):
        for k,v in kwargs.iteritems():
            self._original_settings.setdefault(k, getattr(settings, k,
                                                          NO_SETTING))
            setattr(settings, k, v)
        if 'INSTALLED_APPS' in kwargs:
            self.syncdb()
    
    def revert(self):
        for k,v in self._original_settings.iteritems():
            if v == NO_SETTING:
                delattr(settings, k)
            else:
                setattr(settings, k, v)
        if 'INSTALLED_APPS' in self._original_settings:
            self.syncdb()
        self._original_settings = {}
        

class SettingsTestCase(TestCase):
    def __init__(self, *args, **kwargs):
        super(SettingsTestCase, self).__init__(*args, **kwargs)
            self.settings_manager = TestSettingsManager()

    def tearDown(self):
        self.settings_manager.revert()

test_something.py

from myapp.test import TestSettingsManager


# a module-level settings manager
SETTINGS_MANAGER = TestSettingsManager()

TEST_APPS = (
    'myproject.apps.appname',
    '...',
    'myproject.apps.appname.tests',
)


def setup(self):
    SETTINGS_MANAGER.set(INSTALLED_APPS=TEST_APPS)
    SETTINGS_MANAGER.syncdb()
    
def teardown(self):
    SETTINGS_MANAGER.revert()
    
class SomethingTestCase(TestCase):
    def test_foo(self):
        self.assertTrue(True, "Yay")