Merge pull request #295 from ucoProject/BugFix-CP-79

Add test for sh:datatype count validity

tests/Makefile

@@ -47,6 +47,10 @@ all:
 check: \
   inheritance_review.ttl \
   uco_monolithic.ttl
+	source venv/bin/activate \
+	  && pytest \
+	    --ignore examples \
+	    --log-level=DEBUG
 	$(MAKE) \
 	  --directory examples \
 	  check

tests/test_uco_monolithic.py

@@ -0,0 +1,60 @@
+#!/usr/bin/env python3
+
+# This software was developed at the National Institute of Standards
+# and Technology by employees of the Federal Government in the course
+# of their official duties. Pursuant to title 17 Section 105 of the
+# United States Code this software is not subject to copyright
+# protection and is in the public domain. NIST assumes no
+# responsibility whatsoever for its use by other parties, and makes
+# no guarantees, expressed or implied, about its quality,
+# reliability, or any other characteristic.
+#
+# We would appreciate acknowledgement if the software is used.
+
+import os
+
+import rdflib.plugins.sparql
+
+def test_max_1_sh_datatype_per_property_shape():
+    """
+    This enforces the maximum sh:datatype count of 1, as specified here:
+
+    "A shape has at most one value for sh:datatype."
+    https://www.w3.org/TR/shacl/#DatatypeConstraintComponent
+
+    This is encoded in the SHACL ontology with the statement 'sh:DatatypeConstraintComponent-datatype sh:maxCount 1 .'
+    """
+    expected = set()  # This set is intentionally empty.
+    computed = set()
+
+    graph = rdflib.Graph()
+    graph.parse(os.path.join(os.path.dirname(__file__), "uco_monolithic.ttl"))
+    assert len(graph) > 0, "Failed to load uco_monolithic.ttl."
+
+    nsdict = {
+      "sh": rdflib.SH
+    }
+
+    query_object = rdflib.plugins.sparql.prepareQuery("""\
+SELECT ?nClass ?nPath ?lConstraintDatatypeTally
+WHERE {
+  {
+    SELECT ?nClass ?nPath (COUNT(DISTINCT ?nConstraintDatatype) AS ?lConstraintDatatypeTally)
+    WHERE {
+      ?nClass
+        sh:property ?nPropertyShape ;
+        .
+
+      ?nPropertyShape
+        sh:datatype ?nConstraintDatatype ;
+        sh:path ?nPath ;
+        .
+    } GROUP BY ?nClass ?nPath
+  }
+
+  FILTER (?lConstraintDatatypeTally > 1)
+}
+""", initNs=nsdict)
+    for result in graph.query(query_object):
+        computed.add(result)
+    assert expected == computed