Test modules in PyTest - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a test module in pytest?

A test module is a Python file that contains test functions or classes. Pytest automatically finds and runs tests inside these modules.

beginner

How should you name a test module for pytest to recognize it automatically?

Name the file starting with test_ or ending with _test.py. For example, test_example.py or example_test.py.

beginner

Why is it important to keep test modules separate from application code?

Separating test modules helps keep code organized, makes tests easier to find, and prevents accidental execution of tests in production.

intermediate

What is the role of __init__.py in test directories?

In pytest, __init__.py files are optional. They can make test directories into packages but are not required for pytest to discover tests.

beginner

How can you run tests from a specific test module using pytest?

Use the command pytest path/to/test_module.py. This runs all tests inside that module only.

Which file name will pytest automatically recognize as a test module?

A mytests.py

B math_tested.py

C example.py

D test_math.py

Pytest recognizes files starting with 'test_' or ending with '_test.py'. 'test_math.py' fits this pattern.

What does pytest look for inside a test module to run tests?

A Functions ending with '_check'

B Any function with a docstring

C Functions or classes starting with 'test'

D Only classes named 'Test'

Pytest runs functions or methods whose names start with 'test' inside test modules.

If you want to run tests only from a single test module, what command do you use?

A pytest test_module.py

B pytest -m test_module

C pytest --module test_module

D pytest run test_module

Running 'pytest test_module.py' runs tests only from that file.

Is it necessary to have an __init__.py file in a test directory for pytest to find tests?

A No, pytest can find tests without it

B Yes, always required

C Only if tests are in subdirectories

D Only for Python versions below 3.6

Pytest can discover tests without __init__.py files in test directories.

Why should test modules be kept separate from application code?

A To reduce file size

B To organize code and avoid running tests in production

C To make tests run faster

D To prevent syntax errors

Separating test modules helps keep code organized and prevents accidental test runs in production.

Explain how pytest discovers and runs tests inside test modules.

Think about file names, function names, and how pytest finds tests.

Describe best practices for organizing test modules in a Python project using pytest.

Consider how to keep tests easy to find and run.