Testing the Reaction Plane Fit package

Tests are implemented using pytest. To execute the testing, I tend to use something like:

$ pytest -l --cov=reaction_plane_fit --cov-report html --cov-branch --durations=5 --mpl tests/

This assumes you are running from the root repository folder and will report on which tests are the slowest as well as provide a coverage report for (in this case) the entire reaction_plane_fit module. The branch coverage is particularly useful to help avoid missing coverage over control flow.

There are two particularly noteworthy classes of marked tests:

• ROOT: Tests which require ROOT.
• slow: Tests which are slow, as they run the entire fit code. These are particularly slow because of the error calculation.

Recall that a particular class of tests (named CLASS in this example) can be skipped by passing -m "not CLASS" argument to pytest.

Installing the test dependencies

Beyond ROOT (which is required for tests marked as “ROOT”), the package test dependencies can be installed with:

$ pip install -e .[tests]

Image comparisons

Image comparisons are performed via pytest-mpl. To generate the comparison images, run in the tests directory:

$ pytest --mpl-generate-path=baseline

This will create comparison images in the tests/baseline directory. Once the comparisons have been created, you can compare the images by passing the option --mpl to pytest. Note that if the argument is not passed, the test code itself will be run, but the image won’t be compared.

Note that if a new figure is added, it is up to you to generate and add the baseline image locally. Travis will only do the comparison, not the generation.