OWL RL creates invalid triples when working on PROV-O ontology

test_owlrl_literal_subject.py

import logging
import sys

import owlrl
import rdflib
from owlrl import OWLRL_Extension
from rdflib import Graph, Literal

logger = logging.getLogger(__name__)


def find_literal_subject_triples(graph: Graph):
    return list(
        filter(
            lambda triple: isinstance(triple[0], Literal),
            graph,
        ),
    )


def test_owlrl_literal_subject():
    logger.info(sys.version)
    logger.info('rdflib=={}'.format(
        rdflib.__version__,
    ))
    logger.info('owlrl=={}'.format(
        owlrl.__version__,
    ))

    graph = Graph()
    graph.parse('http://www.w3.org/ns/prov#')
    assert not find_literal_subject_triples(graph), (
        'Import of PROV-O ontology creates triples where Literal is a subject.'
    )

    owlrl.DeductiveClosure(OWLRL_Extension).expand(graph)
    literal_triples = find_literal_subject_triples(graph)
    assert not literal_triples, (
        'OWL RL creates triples with literal as subject. Example: {t}'.format(
            t=literal_triples[0],
        )
    )

Output:

FAILED         [100%]
2021-11-13 21:43:32,407 [INFO] tests.test_experiments.test_owlrl_literal_subject: 3.8.1 (default, Feb 21 2020, 23:12:01) 
[GCC 9.2.1 20191008]
2021-11-13 21:43:32,407 [INFO] tests.test_experiments.test_owlrl_literal_subject: rdflib==6.0.1
2021-11-13 21:43:32,407 [INFO] tests.test_experiments.test_owlrl_literal_subject: owlrl==5.2.3

tests/test_experiments/test_owlrl_literal_subject.py:20 (test_owlrl_literal_subject)
test_owlrl_literal_subject.py:38: in test_owlrl_literal_subject
    assert not literal_triples, (
E   AssertionError: OWL RL creates triples with literal as subject. Example: (rdflib.term.Literal('has_anchor'), rdflib.term.URIRef('http://www.w3.org/2002/07/owl#sameAs'), rdflib.term.Literal('has_anchor'))
E   assert not [(rdflib.term.Literal('has_anchor'), rdflib.term.URIRef('http://www.w3.org/2002/07/owl#sameAs'), rdflib.term.Literal('...rov-n-20130430/#expression-attribution', datatype=rdflib.term.URIRef('http://www.w3.org/2001/XMLSchema#anyURI'))), ...]