Added test for ForwardRuleReasonerRDFS rdfs9 rule

Author: patrickwestphal

sansa-inference-spark/src/test/resources/forward_chaining/axioms/test_rdfs9.owl

@@ -0,0 +1,19 @@
+Prefix(:=<http://ex.com/default#>)
+
+Ontology(<http://ex.com/ont/sample1.owl>
+  <http://ex.com/ont/release/123/sample1.owl>
+
+  Declaration(Class(:Cls01))
+  Declaration(Class(:Cls02))
+  Declaration(Class(:Cls03))
+
+  SubClassOf(:Cls02 :Cls01)
+
+  Declaration(NamedIndividual(:indivA))
+  Declaration(NamedIndividual(:indivB))
+  Declaration(NamedIndividual(:indivC))
+
+  ClassAssertion(:Cls01 :indivA)
+  ClassAssertion(:Cls02 :indivB)
+  ClassAssertion(:Cls03 :indivC)
+)

sansa-inference-spark/src/test/scala/net/sansa_stack/inference/spark/forwardchaining/axioms/ForwardRuleReasonerRDFSTest.scala

@@ -194,4 +194,28 @@ class ForwardRuleReasonerRDFSTest extends FunSuite with SharedSparkContext with
       df.getOWLAnnotationAssertionAxiom(annProp01, indivA.getIRI,
         df.getOWLLiteral("wxyz"))))
   }
+
+  /**
+    * rdfs9
+    *   Condition:
+    *     xxx rdfs:subClassOf yyy .
+    *     zzz rdf:type xxx .
+    *   Consequence:
+    *     zzz rdf:type yyy .
+    */
+  test("Rule rdfs9 should return correct results") {
+    val cls01 = df.getOWLClass(defaultPrefix + "Cls01")
+    val indivB = df.getOWLNamedIndividual(defaultPrefix + "indivB")
+
+    val input = getClass.getResource(resourcePath + "test_rdfs9.owl").getPath
+
+    val axiomsRDD = spark.owl(Syntax.FUNCTIONAL)(input)
+    val reasoner = new ForwardRuleReasonerRDFS(sc, sc.defaultMinPartitions)
+    val inferred: Seq[OWLAxiom] = reasoner.apply(axiomsRDD).collect()
+
+    // One axiom should be inferred:
+    // ClassAssertion(:Cls01 :indivB)
+    assert(inferred.size == 1)
+    assert(inferred.contains(df.getOWLClassAssertionAxiom(cls01, indivB)))
+  }
 }