This document discusses the importance of testing in Django and provides examples of how to write tests. It describes how the Pinax project added tests after users were able to incorrectly edit ticket statuses. It recommends writing unit tests using the Django testing framework and provides a pattern for organizing and writing tests, including setting up test data and individual test methods. The document emphasizes that code without tests is "broken by design" and that writing tests improves code quality and avoids embarrassment.

1. Testing in Django Why and how you should test in Django

2. Code without tests is broken as designed Jacob Kaplan-Moss

3. The Pinax Example http://code.pinax.com/tasks Problem: Anyone with account could edit ticket status.

4. The Pinax Example Example of why this needed to be changed: User adds ticket to a release already under feature freeze. User moves it to resolved. Core developers have to remember every ticket.

5. The Pinax Example Easy fix: Django already supports groups and permissions add a new permission method to the state_transition tuple

6. The Pinax Example Works! Looks fine in my browser! Looks fine in James Tauber's browser!

7. Flashback Pycon 2009 Daniel Mizyrycki, pythonista and hang glider enthusiast Nixes the ability for anonymous users to add/modify tasks Writes two tests to confirm his change works

8. ERROR - Test Fail!

9. The Pinax Example Daniel's tests toss out an error! Anonymous users break is_task_manager method doesn't allow for task viewing by anonymous users Fix is easy:

10. Code without tests is broken as designed Jacob Kaplan-Moss

11. What about... Selenium... Windchill... Nose... Twill... Your test system of choice... All good stuff but outside the scope of this presentation.

12. Doctest or Unittest?

13. My pros and cons of Doctest Pros Easy to learn Documents your code Is pretty with RST Cons Kinda hard to maintain Weirdness on assertions

14. My pattern for Django unit tests Via Django Admin, add some sample data In tasks application, mkdir fixtures Via command line: ./manage.py dumpdata tasks > apps/tasks/fixtures/test_tasks.json

15. My pattern for Django unit tests mkdir 'tests' folder in tasks touch test_authentication.py in tasks/tests touch __init__.py folder in tasks/tests edit __init__.py to include: from test_authentication.py import *

16. My pattern for Django unit tests The test setup:

17. My pattern for Django unit tests The test:

18. My pattern for Django unit tests Run the test! python manage.py test tasks

19. A bigger test See how each method I write tests a different thing. Seems like a good pattern right now. But you always find your old tests look silly. You get better at writing tests the more you do it.

20. Things I like about tests Avoidance of embarrassment Looks good The rush

21. Questions? Comments?