Adding Tests

Ensure you have installed the development dependencies by following the instructions in the installation guide. To run all tests, use the following command:

invoke test

PyTest

Tests can be added to the tests directory. PyTest will automatically discover and run these tests. They should be named test_*.py, and the test functions should be named test_*. See the PyTest documentation for more information.

Use this PyTest style tests for parameterized tests, tests that require fixtures, and tests that require setup.

These tests can be run with:

pytest

Or to run a specific test

pytest tests/test_*.py

Or to run with the same configuration as continuous integration:

invoke test.unit

Doctest

Doctest allows you to write tests directly in the docstrings of your code, making it easier to keep documentation up-to-date. The tests are written as examples in a Python interactive shell.

Use doctest style test to document code with simple tested examples.

Here’s an example of a function with a doctest:

def hello_world():
    """
    >>> hello_world()
    Hello, World!
    """
    print("Hello, World!")

You can run this test with:

pytest --doctest-modules -k src

The -k src flag tells PyTest to run tests only in the src directory. This is useful if you only want to run doctests in source code but not PyTest tests.

Alternatively, you can run all unit tests with the same configuration as continuous integration:

invoke test.unit

Notebooks

Tests can be added to the notebooks directory. These tests are written in the form of Jupyter Notebooks and are run using the nbmake extension for PyTest.

Use this type of test for tests that provide tutorials, documentation, and examples. They should be easy to read and understand.

Just these tests can be run with:

invoke test.nb

If you need to overwrite the notebooks with the output, use:

invoke test.nb --overwrite