Install Pytest

For this book we’re going to use Pytest as the testing framerwork and expects as our assertion library.

How to install Pytest and Expects

In order to add a new library in our project we just need to run the following command:

poetry add pytest expects

If everything works fine now we’re in a position to create our first test.

Validate Pytest is installed

You can find all the code for this chapter here

Once you have Pytest installed you need to create a new file called test_foo.py inside the src folder with the following code (right now don’t care about it!):

from expects import expect, equal

class TestFoo:
  def test_bar(self) -> None:
        expect(1).to(equal(1))

Save the file and run the following command in the terminal:

poetry run pytest

You should see something like these results:

test_foo.py .                                        [100%]
==================== 1 passed in 0.01s ====================