Hypothesis is a property-based testing library that generates random data for testing code. It simplifies examples, remembers interesting inputs, and can deal with complex data types. The hypothesis-django library extends Hypothesis for testing Django applications by providing custom field types, generating child models, and fixtures. The presentation introduced Hypothesis and hypothesis-django, explained why property-based testing is useful, and provided instructions for getting started.

1. Hypothesis
Randomised testing for
Django
Rae Knowler, DjangoCon Europe 2015

2. Introduction

3. Rae Knowler
CKAN, Symfony, Django
@RaeKnowler
they/their/them

4. David MacIver and Sinister Katze
@DRMacIver @sinister_katze

5. Hypothesis
Property based testing library
Inspired by Haskell’s Quickcheck
http://hypothesis.readthedocs.org

6. Hypothesis

7. Why is it so great?

8. Why is it so great?
● Lots of randomised data

9. Why is it so great?
● Lots of randomised data
● Simplifies examples

10. Why is it so great?
● Lots of randomised data
● Simplifies examples
● Remembers interesting inputs

11. Why is it so great?
● Lots of randomised data
● Simplifies examples
● Remembers interesting inputs
● Can deal with complex data types

12. Why is it so great?
● Lots of randomised data
● Simplifies examples
● Remembers interesting inputs
● Can deal with complex data types
● Works with pytest and unittest

13. Hypothesis +
Django

14. hypothesis-django

15. hypothesis-django
● Custom field types

16. hypothesis-django
● Custom field types
● Generate child models

17. hypothesis-django
● Custom field types
● Generate child models
● Fixtures (new!)

18. Getting started

19. Install
pip install hypothesis
pip install hypothesis-django

20. Demo

27. Summary

28. Links
hypothesis.readthedocs.org
github.com/bellisk/hypothesis-django-example
@RaeKnowler
raeknowler.com

29. Thank you!