Mastering Pytest Fixtures
Fixtures are the backbone of pytest testing. They set up objects — like a SparkSession, a sample DataFrame, or a database connection — that your tests can use. Instead of constructing the same input data in ten different test functions, you define a fixture once and inject it where needed. In the previous post we covered the fundamentals of testing and mocking; now it's time to eliminate duplication and make your test suite faster and easier to maintain.
This post covers everything you need to know about fixtures: how to define them, the different scopes available, how to use yield for setup and teardown, when to reach for autouse=True, and how conftest.py acts as a shared repository for fixtures across your entire test suite.
Defining a Fixture and Scoping It
A fixture is just a function decorated with @pytest.fixture. You can request it in a test by including its name as a parameter:
