How to mock django settings attribute used in another module?

Question

Lets say module a code:

from django.conf import settings
print settings.BASE_URL # prints http://example.com

In tests.py I want to mock the BASE_URL to http://localhost

I have tried the following:

with mock.patch('django.conf.settings.BASE_URL', 'http://localhost'):
    pass

with mock.patch('a.settings.BASE_URL', 'http://localhost'):
    pass

from a import settings

with mock.patch.object(settings, 'BASE_URL', 'http://localhost'):
    pass

import a

with mock.patch.object(a.settings, 'BASE_URL', 'http://localhost'):
    pass

None of the above worked.

Answer 1

Try to use context manager settings() built-in django.

with self.settings(BASE_URL='http://localhost'):
    # perform your test

https://docs.djangoproject.com/en/dev/topics/testing/tools/#django.test.SimpleTestCase.settings