Added test for Forw.RuleReasonerOWLHorst O7a rule

Author: patrickwestphal

sansa-inference-spark/src/test/resources/forward_chaining/axioms/test_o7a.owl

@@ -0,0 +1,18 @@
+Prefix(:=<http://ex.com/default#>)
+
+Ontology(<http://ex.com/ont/sample1.owl>
+  <http://ex.com/ont/release/123/sample1.owl>
+
+  Declaration(ObjectProperty(:objProp01))
+  Declaration(ObjectProperty(:objProp02))
+  Declaration(ObjectProperty(:objProp03))
+
+  InverseObjectProperties(:objProp01 :objProp02)
+
+  Declaration(NamedIndividual(:indivA))
+  Declaration(NamedIndividual(:indivB))
+  Declaration(NamedIndividual(:indivC))
+
+  ObjectPropertyAssertion(:objProp01 :indivA :indivB)
+  ObjectPropertyAssertion(:objProp03 :indivB :indivC)
+)

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

@@ -412,4 +412,30 @@ class ForwardRuleReasonerOWLHorstTest extends FunSuite with SharedSparkContext w
     assert(inferred.contains(df.getOWLObjectPropertyAssertionAxiom(objProp01, indivA, indivD)))
     assert(inferred.contains(df.getOWLObjectPropertyAssertionAxiom(objProp01, indivB, indivD)))
   }
+
+  /**
+    * O7a:
+    *   Condition:
+    *     p owl:inverseOf q
+    *     v p w
+    *   Consequence:
+    *     w q v
+    */
+  test("Rule O7a should return correct results") {
+    val indivA = df.getOWLNamedIndividual(defaultPrefix + "indivA")
+    val indivB = df.getOWLNamedIndividual(defaultPrefix + "indivB")
+    val objProp02 = df.getOWLObjectProperty(defaultPrefix + "objProp02")
+
+    val input = getClass.getResource(resourcePath + "test_o7a.owl").getPath
+
+    val axiomsRDD = spark.owl(Syntax.FUNCTIONAL)(input)
+    val reasoner = new ForwardRuleReasonerOWLHorst(sc, sc.defaultMinPartitions)
+    val inferred: Seq[OWLAxiom] = reasoner.apply(axiomsRDD).collect()
+
+    // One axiom should be inferred:
+    // ObjectPropertyAssertion(:objProp02 :indivB :indivA)
+    assert(inferred.size == 1)
+    assert(inferred.contains(
+      df.getOWLObjectPropertyAssertionAxiom(objProp02, indivB, indivA)))
+  }
 }