feat(test): Add test relation without domain and range

test/data/test_relation_without_domain_range.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.
+:SecondClass a owl:Class.
+
+:rel1 a owl:ObjectProperty.

test/data/test_relation_without_domain_range.yams

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

test/test_owl2yams.py

@@ -43,6 +43,12 @@
     def test_transform_hierarchy(self):
         self._load_owl_and_yams("test_hierarchy.owl", "test_hierarchy.yams")
 
+    def test_transform_relation_without_domain_range(self):
+        self._load_owl_and_yams(
+            "test_relation_without_domain_range.owl",
+            "test_relation_without_domain_range.yams",
+        )
+
     def test_raise_multi_class(self):
         with self.assertRaises(ValueError):
             self._load_owl_and_yams("test_multi_class.owl")