Fixture factories in PyTest - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a fixture factory in pytest?

A fixture factory is a function that returns a pytest fixture. It allows creating fixtures dynamically with parameters, helping to reuse setup code with different data.

intermediate

How do you create a fixture factory in pytest?

Define a regular function that returns a fixture function. Use @pytest.fixture inside the factory or return a nested function decorated with @pytest.fixture to generate fixtures dynamically.

beginner

Why use fixture factories instead of regular fixtures?

Fixture factories let you create multiple fixtures with different parameters without repeating code. This makes tests cleaner and easier to maintain.

intermediate

Example: How to write a fixture factory that creates user objects with different names?

import pytest

def user_factory(name):
    @pytest.fixture
    def _user():
        return {'name': name}
    return _user

Use by calling user_factory('Alice') to get a fixture for user named Alice.

intermediate

What is the benefit of using fixture factories for parameterized tests?

Fixture factories allow creating fixtures with different parameters easily, which helps run the same test logic with varied data without duplicating fixtures.

What does a fixture factory in pytest return?

A A fixture function

B A test case

C A test report

D A test runner

A fixture factory returns a fixture function that pytest can use to set up test data or state.

Why use fixture factories instead of multiple similar fixtures?

A To reduce code duplication and improve reuse

B To slow down test execution

C To make tests harder to read

D To avoid using pytest

Fixture factories help reduce repeated code by generating fixtures dynamically with different parameters.

Which decorator is used to mark a fixture in pytest?

A @pytest.run

B @pytest.fixture

C @pytest.test

D @pytest.assert

The @pytest.fixture decorator marks a function as a fixture in pytest.

How can you pass parameters to a fixture created by a fixture factory?

A By modifying pytest.ini

B By using global variables

C By calling the factory function with arguments

D By using command line options only

You pass parameters by calling the fixture factory function with arguments to create customized fixtures.

What is a common use case for fixture factories?

A Installing pytest plugins

B Running tests in parallel

C Generating test reports

D Creating test data objects with different attributes

Fixture factories are often used to create test data objects with varying attributes for flexible testing.

Explain how fixture factories improve test code reuse in pytest.

Think about how you can create many similar fixtures without writing each one separately.

Describe the steps to create and use a fixture factory in pytest with an example.

Consider a simple example like creating user objects with different names.