Test discovery rules in PyTest - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is test discovery in pytest?

Test discovery is the process pytest uses to find test files and test functions automatically before running them.

beginner

How does pytest identify test files by default?

Pytest looks for files matching the pattern test_*.py or *_test.py in the current directory and subdirectories.

beginner

What naming convention does pytest use to find test functions inside test files?

Pytest finds test functions that start with test_ inside test files.

intermediate

Can pytest discover tests inside classes? If yes, what is the rule?

Yes, pytest discovers test methods inside classes that start with Test and do not have an __init__ method. Test methods must start with test_.

intermediate

How can you customize test discovery patterns in pytest?

You can customize test discovery by configuring python_files, python_functions, and python_classes in pytest.ini or other config files, or by using command-line options like --pyargs.

Which file name will pytest discover by default?

A TestExample.py

B example_tested.py

C example.py

D test_example.py

Pytest discovers files starting with 'test_' or ending with '_test.py'. 'test_example.py' matches this pattern.

Which function name will pytest recognize as a test inside a test file?

A check_function

B function_test

C test_function

D TestFunction

Pytest looks for functions starting with 'test_' as test functions.

Which class name will pytest consider for test discovery?

A suiteTest

B TestSuite

C testsuite

D SuiteTest

Pytest discovers classes starting with 'Test' for test methods.

How can you change the default test file pattern in pytest?

A Edit pytest.ini and set python_files

B Rename files manually

C Use a different Python version

D Change function names

You can configure 'python_files' in pytest.ini to change which files pytest discovers.

What happens if a test class has an __init__ method?

A Pytest will skip discovering tests inside it

B Pytest will raise an error

C Pytest will discover it normally

D Pytest will run only __init__

Pytest skips test classes that define an __init__ method.

Explain how pytest discovers test files and test functions by default.

Think about file and function naming conventions.

Describe how to customize test discovery rules in pytest using configuration files.

Look into pytest configuration options.