Working on RDFLib#955 embedded triples in values clasuses need to be …

…well formed.
JervenBolleman · Mar 14, 2020 · c3b9d36 · c3b9d36
1 parent 6049464
commit c3b9d36
Show file tree

Hide file tree

Showing 2 changed files with 33 additions and 3 deletions.
diff --git a/rdflib/plugins/sparql/parser.py b/rdflib/plugins/sparql/parser.py
@@ -410,9 +410,16 @@ def _hexExpand(match):
 GraphOrDefault = ParamList('graph', Keyword(
     'DEFAULT')) | Optional(Keyword('GRAPH')) + ParamList('graph', iri)
 
+# Inside a values clause the EmbeddedTriple must be fully resolvable.
+KnownEmbTP = Suppress('<<') + iri + (iri | A) + (iri | RDFLiteral | NumericLiteral | BooleanLiteral) + Suppress('>>')
+KnownEmbTP.setParseAction(lambda x:
+                          rdflib.EmbeddedTriple(subject=x[0],
+                                                predicate=x[1],
+                                                object=x[2]))
+
+
 # [65] DataBlockValue ::= iri | RDFLiteral | NumericLiteral | BooleanLiteral | 'UNDEF'
-DataBlockValue = iri | RDFLiteral | NumericLiteral | BooleanLiteral | Keyword(
-    'UNDEF')
+DataBlockValue = iri | RDFLiteral | NumericLiteral | BooleanLiteral | Keyword('UNDEF') | KnownEmbTP
 
 # [78] Verb ::= VarOrIri | A
 Verb = VarOrIri | A
@@ -435,7 +442,8 @@ def _hexExpand(match):
 #VarOrBlankNodeOrIriOrLitOrEmbTP = Forward()
 #VarOrBlankNodeOrIriOrLitOrEmbTP <<= Var | BlankNode | iri | RDFLiteral | NumericLiteral | BooleanLiteral | VarOrBlankNodeOrIriOrLitOrEmbTP
 VarOrBlankNodeOrIriOrLitOrEmbTP = Var | BlankNode | iri | RDFLiteral | NumericLiteral | BooleanLiteral
-EmbTP = Suppress('<<') + VarOrBlankNodeOrIriOrLitOrEmbTP + Verb+ VarOrBlankNodeOrIriOrLitOrEmbTP + Suppress('>>')
+
+EmbTP = Suppress('<<') + VarOrBlankNodeOrIriOrLitOrEmbTP + Verb + VarOrBlankNodeOrIriOrLitOrEmbTP + Suppress('>>')
 EmbTP.setParseAction(lambda x:
                      rdflib.EmbeddedTriple(subject=x[0],
                                            predicate=x[1],

diff --git a/test/test_sparql_star.py b/test/test_sparql_star.py
@@ -1,5 +1,6 @@
 from rdflib import Graph
 from rdflib.namespace import RDF, Namespace
+from pyparsing import ParseException
 import unittest
 
 
@@ -93,5 +94,26 @@ def test_constant_sparql_object(self):
         rl = list(res)
         self.assertEqual(1 , len(rl))
 
+    def test_constant_sparql_star_values(self):
+        g = Graph()
+        g.parse(data=self.reif_as_subject, format="ttl")
+        res = g.query('''PREFIX ex:<http://example.org/> SELECT * WHERE {
+        VALUES(?reif) {(<< ex:subject ex:predicate ex:object>>)}
+        ?reif a ex:about  . 
+        }''')
+        rl = list(res)
+        self.assertEqual(1 , len(rl))
+
+    #This should fail as the embedded triple is not well formed
+    def test_non_constant_sparql_star_values(self):
+        g = Graph()
+        g.parse(data=self.reif_as_subject, format="ttl")
+        with self.assertRaises(ParseException):
+            g.query('''PREFIX ex:<http://example.org/> SELECT * WHERE {
+           VALUES(?reif) {(<< ex:subject ex:predicate ?o>>)}
+           ?reif a ex:about  . 
+           }''')
+
+
 if __name__ == '__main__':
     unittest.main()