feat(test): Add test relation

test/data/test_relation.owl

+@prefix : <http://loutre.fr/>.
+@prefix owl: <http://www.w3.org/2002/07/owl#>.
+@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>.
+@prefix xsd: <http://www.w3.org/2001/XMLSchema#>.
+
+:FirstClass a owl:Class.
+
+:rel1 a owl:ObjectProperty;
+    rdfs:domain :FirstClass;
+    rdfs:range :FirstClass.

test/data/test_relation.yams

+from yams.buildobjs import *
+
+class FirstClass(EntityType):
+    pass
+
+class rel1(RelationDefinition):
+    subject = ('FirstClass',)
+    object = ('FirstClass',)
+

test/test_owl2yams.py

@@ -31,6 +31,9 @@
     def test_transform_attribute(self):
         self._load_owl_and_yams("test_attribute.owl", "test_attribute.yams")
 
+    def test_transform_relation(self):
+        self._load_owl_and_yams("test_relation.owl", "test_relation.yams")
+
 
 if __name__ == "__main__":
     unittest.main()