pytest Quick Start Guide

Writing and running tests

• Always use a virtual environment to manage your packages and dependencies. This advice goes for any Python project.
• pytest introspection features make it easy to express your checks concisely; it is easy to compare dictionaries, text, and lists directly.
• Check exceptions with pytest.raises and warnings with pytest.warns.
• Compare floating-point numbers and arrays with pytest.approx.
• Test organization; you can inline your tests with your application code or keep them in a separate directory.
• Select tests with the -k flag: -k test_something.
• Stop at the first failure with -x.
• Remember the awesome refactoring duo: --lf -x.
• Disable output capturing with -s.
• Show the complete summary of test failures, xfails, and skips ...