introduce test coverage calculation

README.md

@@ -122,6 +122,10 @@ This is done via `pip install --editable .` in the environment file.
 Otherwise the source is not in the pythonpath and the tests cannot import it.
 It uses the `setup.py` with the `setup.cfg` config.
 The tests are run with `pytest` in the main directory.
+Test coverage can be calculated with the
+[coverage](https://coverage.readthedocs.io) module:
+`coverage run --source=src -m pytest`
+and shown with `coverage report` or `coverage html` afterwards.
 
 To create the documentation go to the `docs` directory: `cd docs` and run `make html`.
 Then under `docs/_build/html/index.html` you can view the created documentation.

environment.yml

@@ -14,6 +14,7 @@ dependencies:
     - sphinx
     - SQLAlchemy-Utils>=0.31
     - SQLAlchemy>=1.0
+    - coverage
     - pip
     # packages to be installed via pip:
     - pip: