Pytest - Test Framework

Main point

Pytest is a programmer-friendly Python test framework. It makes it easy to write small tests, yet scales to support complex cases.

  • Major pytest features:

    • Battle-tested and mature.
    • Informative test failures.
    • Less verbose (plain assert vs. self.assertEqual, self.assertGreaterEqual, etc.).
    • Classes are not required.
    • A far more convenient way to write setup & teardown functions with fixtures.
    • Parameterized tests.
    • Fantastic test runner (a.o. marker- and name-based test selection).
    • Rich plugin architecture.
    • Auto-discovery of test modules and functions.
    • Runs unittest and nose test suites out-of-the-box.

  • You can easily set test runner default flags by defining them in a configuration file called pytest.ini. You can find an example in Big-Bang-py.

  • Recommended test runner plugins:

    • pytest-cov - prints coverage report at the end of test runner report.
    • pytest-mock - adds mocker fixture, which makes mocks easier and more readable.
    • pytest-socket - disables socket calls during tests to ensure network calls are prevented. Amazing to protect yourself against incidental DB or API calls.
    • pytest-sugar - makes test runner report even nicer.

  • Useful content: