Make All Tests Pass

Learn to make all tests pass in test-driven development.

In this step, we rerun the tests, including older ones, and make sure they pass. Therefore, we must make sure that the feature being added doesn’t make the previous test fail, thereby breaking past functionality.

How does it work?

Here, we basically redo the action we performed in step two. However, this time, we shouldn’t get any failed tests if the actual code we write was well implemented:

$ python test

We can also run it using Docker in the following way:

$ docker-compose exec web python test

Since the tests must pass because the feature is now implemented, the output would be something similar to this:

Ran 4 tests in 0.026s

Destroying test database for alias 'default'...

Because the tests were successful, we get an output of OK.

Working example

Here’s a working example.

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