Testing

We’re using a mix of Django’s Unit Testing and nose.

Running Tests

To run the whole shebang use:

python manage.py test

There are a lot of options you can pass to adjust the output. Read the docs for the full set, but some common ones are:

  • -P to prevent nose adding the lib directory to the path.
  • --noinput tells Django not to ask about creating or destroying test databases.
  • --logging-clear-handlers tells nose that you don’t want to see any logging output. Without this, our debug logging will spew all over your console during test runs. This can be useful for debugging, but it’s not that great most of the time. See the docs for more stuff you can do with nose and logging.

Our continuous integration server adds some additional flags for other features (for example, coverage statistics). To see what those commands are check out the .travis.yml file.

There are a few useful makefile targets that you can use:

Run all the tests:

make test

If you need to rebuild the database:

make test_force_db

To fail and stop running tests on the first failure:

make tdd

If you wish to add arguments, or run a specific test, overload the variables (check the Makefile for more information):

make SETTINGS=settings_mkt ARGS='--verbosity 2 zamboni.mkt.site.tests.test_url_prefix:MiddlewareTest.test_get_app' test

Those targets include some useful options, like the --with-id which allows you to re-run only the tests failed from the previous run:

make test_failed

Database Setup

If you want to re-use your database instead of making a new one every time you run tests, set the environment variable REUSE_DB.

REUSE_DB=1 python manage.py test

Writing Tests

We support two types of automated tests right now and there are some details below but remember, if you’re confused look at existing tests for examples.

Unit/Functional Tests

Most tests are in this category. Our test classes extend django.test.TestCase and follow the standard rules for unit tests. We’re using JSON fixtures for the data.

External calls

Connecting to remote services in tests is not recommended, developers should mock_ out those calls instead.

To enforce this we run Jenkins with the nose-blockage plugin, that will raise errors if you have an HTTP calls in your tests apart from calls to the domains 127.0.0.1 and localhost.

Why Tests Fail

Tests usually fail for one of two reasons: The code has changed or the data has changed. An third reason is time. Some tests have time-dependent data usually in the fixtues. For example, some featured items have expiration dates.

We can usually save our future-selves time by setting these expirations far in the future.

Localization Tests

If you want test that your localization works then you can add in locales in the test directory. For an example see devhub/tests/locale. These locales are not in the normal path so should not show up unless you add them to the LOCALE_PATH. If you change the .po files for these test locales, you will need to recompile the .mo files manually, for example:

msgfmt --check-format -o django.mo django.po