Test fixtures with pytest in Flask - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a test fixture in pytest?

A test fixture is a setup function that prepares the environment for tests. It can create objects, set states, or provide resources needed by tests.

beginner

How do you define a fixture in pytest?

You define a fixture by creating a function and decorating it with @pytest.fixture. This function can then be used by tests by adding its name as a parameter.

intermediate

Why use fixtures in Flask testing with pytest?

Fixtures help create a clean and reusable setup for Flask app, test client, and database. This keeps tests simple and avoids repeating setup code.

intermediate

What does the scope parameter in a pytest fixture control?

The scope controls how often the fixture is invoked. For example, function runs before each test, module runs once per file, and session runs once per test session.

intermediate

How can you use a Flask test client fixture in pytest?

Create a fixture that initializes the Flask app and returns app.test_client(). Tests can then use this client to simulate HTTP requests to the app.

What decorator is used to create a fixture in pytest?

A @pytest.fixture

B @pytest.test

C @pytest.setup

D @pytest.run

The correct decorator to define a fixture in pytest is @pytest.fixture.

In Flask testing, what does the test client fixture provide?

A A database connection

B A logging tool

C A user authentication token

D A way to send HTTP requests to the Flask app

The Flask test client lets tests send HTTP requests to the app without running a server.

What does setting scope='module' in a fixture do?

A Runs the fixture once per test function

B Runs the fixture once per test module (file)

C Runs the fixture once per test session

D Runs the fixture before every test class

Scope 'module' means the fixture runs once for all tests in a single file.

How do tests access a fixture's return value?

A By calling the fixture function directly

B By importing the fixture

C By adding the fixture name as a test function parameter

D By using a global variable

Tests receive fixture values by naming the fixture as a parameter in the test function.

Why are fixtures preferred over setup code inside tests?

A Fixtures allow reuse and cleaner test code

B Fixtures run faster than setup code

C Fixtures automatically generate test data

D Fixtures replace the need for assertions

Fixtures help avoid repeating setup code and keep tests clean and organized.

Explain how to create and use a pytest fixture for a Flask test client.

Think about how to prepare the Flask app and provide a client for tests.

Describe the benefits of using test fixtures in pytest when testing Flask applications.

Consider how fixtures help organize and simplify test preparation.