Configure pytest to look in tests by default

docs/index.rst

@@ -31,8 +31,9 @@ We think it's really neat, and we hope you do to!
    practices/code_coverage
    practices/git-lfs
    practices/linting
+   practices/namespace_project
    practices/pipx
    practices/precommit
    practices/pypi
+   practices/unit_testing
    practices/sphinx
-   practices/namespace_project

docs/practices/unit_testing.rst

@@ -0,0 +1,35 @@
+Unit testing
+===============================================================================
+
+What is it? Why do it?
+-------------------------------------------------------------------------------
+
+Unit testing is a method for testing very specific aspects of a code base. The
+various different types of tests cover a wide range of use cases, for a quick intro
+take a look at RealPython's article about unit testing: https://realpython.com/python-testing/#unit-tests-vs-integration-tests
+
+How to manage
+-------------------------------------------------------------------------------
+
+Our template makes use of `pytest <https://docs.pytest.org/en/latest/contents.html>`_
+as the unit testing framework. You have the option to change that at any time,
+but you'll need to make modifications in a few files:
+
+* ``pyproject.toml``
+* ``.github/workflows/testing-and-coverage.yml``
+* ``.github/workflows/smoke-test.yml``
+* ``.pre-commit-config.yaml``
+
+Additionally, we advise that unit tests be placed in the ``./tests`` directory.
+This is not a requirement, but the Continuous Integration and pre-commit checks
+will only look in that directory for tests. If you decide to keep your tests
+elsewhere, you should update the ``[tool.pytest.ini_options]`` section in
+``pyproject.toml`` with the new location so that CI and pre-commit will work as
+expected.
+
+It's also worth noting that if you want to write exploratory tests as you develop
+your code, but you *do not* want those tests to be included in automated test runs,
+feel free to place those tests in a directory outside of the ``./tests`` directory.
+
+Note that ``pytest`` will recursively search subdirectories inside of ``./tests``
+while searching for tests to run.

python-project-template/pyproject.toml.jinja

@@ -60,6 +60,11 @@ build-backend = "setuptools.build_meta"
 
 [tool.setuptools_scm]
 write_to = "src/{{package_name}}/_version.py"
+
+[tool.pytest.ini_options]
+testpaths = [
+    "tests",
+]
 {%- if preferred_linter == 'black' %}
 
 [tool.black]