Enable doctests on modules

This patch enables review of Python code inlined in the `case-utils`
modules' docstrings.

An initial docstring test is also included, because `pytest` reports an
error if it is called and no tests are found.

References:
* https://docs.pytest.org/en/7.1.x/how-to/doctest.html

Signed-off-by: Alex Nelson <[email protected]>

Author: ajnelson-nist

case_utils/ontology/src/ontology_and_version_iris.py

@@ -29,6 +29,11 @@
 def concept_is_cdo_concept(n_concept: rdflib.URIRef) -> bool:
     """
     This function is purposefully distinct from the function used in case_validate.  Within this script, the publishing history of CASE and UCO is reviewed.
+
+    >>> concept_is_cdo_concept(rdflib.URIRef("http://example.org/ontology/Thing"))
+    False
+    >>> concept_is_cdo_concept(rdflib.URIRef("https://ontology.unifiedcyberontology.org/uco/core/UcoThing"))
+    True
     """
     concept_iri = str(n_concept)
     return (

tests/Makefile

@@ -59,6 +59,11 @@ check: \
   check-mypy \
   check-isomorphic_diff \
   check-case_utils
+	source venv/bin/activate \
+	  && pytest \
+	    --doctest-modules \
+	    --log-level=DEBUG \
+	    $(top_srcdir)/case_utils
 	source venv/bin/activate \
 	  && pytest \
 	    --ignore case_utils \