Running tests selectively

Detecting and running all the defined tests in a project is good to verify that everything is working. But most of the development work done while dealing with tests benefits from executing only a subset of all tests.

When adding new code or new tests, it is crucial to iterate quickly through a specific part of the tests and code to narrow your focus.

In this recipe, we will see how to run a subset of available tests with pytest and what parameters to use in different scenarios.

Getting ready

We will use the pytest module among others. We should install the modules by adding them to our requirements.txt file as follows:

$ echo "pytest==5.4.1" >> requirements.txt
$ echo "requests==2.23.0" >> requirements.txt
$ echo "responses==0.10.12" >> requirements.txt
$ echo "freezegun==0.3.15" >> requirements.txt
$ pip install -r requirements.txt

We will use the test files introduced...