Add tests demonstrating forward-slash behaviors in Turtle, JSON-LD, and SPARQL

test/data/variants/forward_slash-asserts.json

@@ -0,0 +1,10 @@
+{
+  "quad_count": 4,
+  "exact_match": true,
+  "has_subject_iris": [
+    "http://example.org/kb/individual-a",
+    "http://example.org/kb/individual-b",
+    "http://example.org/ontology/core/MyClassA",
+    "http://example.org/ontology/core/MyClassB"
+  ]
+}

test/data/variants/forward_slash-variant-prefixed.jsonld

@@ -0,0 +1,33 @@
+{
+  "@context": {
+    "ex": "http://example.org/ontology/",
+    "kb": "http://example.org/kb/",
+    "owl": "http://www.w3.org/2002/07/owl#"
+  },
+  "_comment": [
+    "The JSON-LD spec does not provide a grammar production rule set in,",
+    "EBNF.  However, the section on compact IRIs indicates that an IRI can",
+    "be prefixed at any point that would not result in a suffix starting",
+    "with \"//\".  Hence, an unpaired forward slash, as a legal character of",
+    "an IRI, can appear in the suffix component of a compact IRI.",
+    "https://json-ld.org/spec/latest/json-ld/#compact-iris"
+  ],
+  "@graph": [
+    {
+      "@id": "kb:individual-a",
+      "@type": "ex:core/MyClassA"
+    },
+    {
+      "@id": "ex:core/MyClassA",
+      "@type": "owl:Class"
+    },
+    {
+      "@id": "kb:individual-b",
+      "@type": "ex:core/MyClassB"
+    },
+    {
+      "@id": "ex:core/MyClassB",
+      "@type": "owl:Class"
+    }
+  ]
+}

test/data/variants/forward_slash-variant-prefixed.ttl

@@ -0,0 +1,18 @@
+@prefix ex: <http://example.org/ontology/> .
+@prefix kb: <http://example.org/kb/> .
+@prefix owl: <http://www.w3.org/2002/07/owl#> .
+
+# Spell a class name with prefixing, but have the prefixing NOT include
+# one of the forward-slashed path components.
+# The forward slash must be escaped, according to Turtle grammar
+# production rules grammar rules including and between PN_LOCAL and
+# PN_LOCAL_ESC.
+# https://www.w3.org/TR/turtle/#sec-grammar-grammar
+
+ex:core\/MyClassA a owl:Class .
+
+kb:individual-a a ex:core\/MyClassA .
+
+ex:core\/MyClassB a owl:Class .
+
+kb:individual-b a ex:core\/MyClassB .

test/data/variants/forward_slash.jsonld

@@ -0,0 +1,24 @@
+{
+  "@context": {
+    "kb": "http://example.org/kb/",
+    "owl": "http://www.w3.org/2002/07/owl#"
+  },
+  "@graph": [
+    {
+      "@id": "kb:individual-a",
+      "@type": "http://example.org/ontology/core/MyClassA"
+    },
+    {
+      "@id": "http://example.org/ontology/core/MyClassA",
+      "@type": "owl:Class"
+    },
+    {
+      "@id": "kb:individual-b",
+      "@type": "http://example.org/ontology/core/MyClassB"
+    },
+    {
+      "@id": "http://example.org/ontology/core/MyClassB",
+      "@type": "owl:Class"
+    }
+  ]
+}

test/data/variants/forward_slash.nt

@@ -0,0 +1,4 @@
+<http://example.org/ontology/core/MyClassA> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://www.w3.org/2002/07/owl#Class> .
+<http://example.org/kb/individual-a> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://example.org/ontology/core/MyClassA> .
+<http://example.org/ontology/core/MyClassB> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://www.w3.org/2002/07/owl#Class> .
+<http://example.org/kb/individual-b> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://example.org/ontology/core/MyClassB> .

test/data/variants/forward_slash.ttl

@@ -0,0 +1,10 @@
+@prefix kb: <http://example.org/kb/> .
+@prefix owl: <http://www.w3.org/2002/07/owl#> .
+
+<http://example.org/ontology/core/MyClassA> a owl:Class .
+
+kb:individual-a a <http://example.org/ontology/core/MyClassA> .
+
+<http://example.org/ontology/core/MyClassB> a owl:Class .
+
+kb:individual-b a <http://example.org/ontology/core/MyClassB> .

test/test_graph/test_variants.py

@@ -49,14 +49,26 @@ class GraphAsserts:
 
     quad_count: Optional[int] = None
     exact_match: bool = False
+    has_subject_iris: Optional[List[str]] = None
 
     def check(
         self, first_graph: Optional[ConjunctiveGraph], graph: ConjunctiveGraph
     ) -> None:
+        """
+        if `first_graph` is `None` then this is the first check before any
+        other graphs have been processed.
+        """
         if self.quad_count is not None:
             assert self.quad_count == len(list(graph.quads()))
         if first_graph is not None and self.exact_match:
             GraphHelper.assert_quad_sets_equals(first_graph, graph)
+        if first_graph is None and self.has_subject_iris is not None:
+            subjects_iris = {
+                f"{subject}"
+                for subject in graph.subjects()
+                if isinstance(subject, URIRef)
+            }
+            assert set(self.has_subject_iris) == subjects_iris
 
 
 @dataclass(order=True)
@@ -219,6 +231,8 @@ def test_variants(graph_variant: GraphVariants) -> None:
     assert len(graph_variant.variants) > 0
     first_graph: Optional[ConjunctiveGraph] = None
     first_path: Optional[Path] = None
+    logging.debug("graph_variant.asserts = %s", graph_variant.asserts)
+
     for variant_key, variant_path in graph_variant.variants.items():
         logging.debug("variant_path = %s", variant_path)
         format = guess_format(variant_path.name, fmap=SUFFIX_FORMAT_MAP)

test/test_sparql/test_forward_slash_escapes.py

@@ -0,0 +1,140 @@
+#!/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.
+
+"""
+This test-set demonstrates usage of identifier prefixing and the
+forward-slash character in Turtle, JSON-LD, and SPARQL.  The motivating
+use case originated with attempts to interact with IANA Media Types as
+prefixed concepts, e.g. "application/json" somehow being
+"mime:application/json".
+"""
+
+from test.data import TEST_DATA_DIR
+from test.utils.graph import cached_graph
+from typing import Set
+
+import pytest
+
+from rdflib import Graph
+from rdflib.plugins.sparql.processor import prepareQuery
+from rdflib.plugins.sparql.sparql import Query
+
+query_string_expanded = r"""
+SELECT ?nIndividual
+WHERE {
+  ?nIndividual a <http://example.org/ontology/core/MyClassB> .
+}"""
+
+# NOTE: This is expected to fail.  The SPARQL grammar production rules
+# for prefixed IRIs, especially at production rule PN_LOCAL, have no way
+# to reach the forward-slash or backslash characters.
+# https://www.w3.org/TR/rdf-sparql-query/#grammar
+query_string_prefixed = r"""
+PREFIX ex: <http://example.org/ontology/>
+SELECT ?nIndividual
+WHERE {
+  # NOTE: Syntax is incorrect - forward slash cannot be included in
+  # local component of name.
+  ?nIndividual a ex:core\/MyClassB .
+}"""
+
+PN_LOCAL_BACKSLASH_XFAIL_REASON = """
+    Contrary to the ratified SPARQL 1.1 grammar, the RDFlib SPARQL propcessor
+    accepts backslashes as part of PN_LOCAL which it treats as escape
+    characters.
+
+    There should be a way to instruct the SPARQL parser to operate in strict
+    mode, and in strict mode backslashes should not be permitted in PN_LOCAL.
+
+    See https://github.com/RDFLib/rdflib/issues/1871
+"""
+
+
+def _test_query_prepares(query_string: str) -> None:
+    """
+    Confirm parse behavior of SPARQL engine when a concept would be
+    prefixed at a point that leaves a forward-slash character in the
+    suffix.
+    """
+    nsdict = {
+        "ex": "http://example.org/ontology/",
+        "kb": "http://example.org/kb/",
+        "owl": "http://www.w3.org/2002/07/owl#",
+    }
+    # TODO: A 'strict' flag for prepareQuery is under consideration to
+    # adjust parse behavior around backslash characters.
+    query_object = prepareQuery(query_string, initNs=nsdict)
+    assert isinstance(query_object, Query)
+
+
+def test_query_prepares_expanded() -> None:
+    _test_query_prepares(query_string_expanded)
+
+
+@pytest.mark.xfail(reason=PN_LOCAL_BACKSLASH_XFAIL_REASON)
+def test_query_prepares_prefixed() -> None:
+    with pytest.raises(ValueError):
+        _test_query_prepares(query_string_prefixed)
+
+
+def _test_escapes_and_query(
+    graph: Graph, query_string: str, expected_query_compiled: bool
+) -> None:
+    """
+    Confirm search-results behavior of SPARQL engine when a concept
+    would be prefixed at a point that leaves a forward-slash character
+    in the suffix.
+
+    Note that _test_query_prepares also exercises the expected parse
+    failure.  This parameterized test is more for demonstrating that
+    searching can work without prefixes.
+    """
+    expected: Set[str] = {
+        "http://example.org/kb/individual-b",
+    }
+    computed: Set[str] = set()
+
+    query_compiled: bool = False
+    try:
+        query_object = prepareQuery(query_string)
+        query_compiled = True
+    except Exception:
+        pass
+    assert expected_query_compiled == query_compiled
+
+    for result in graph.query(query_object):
+        computed.add(str(result[0]))
+
+    assert expected == computed
+
+
+def test_escapes_and_query_turtle_expanded() -> None:
+    graph = cached_graph((TEST_DATA_DIR / "variants/forward_slash.ttl",))
+    _test_escapes_and_query(graph, query_string_expanded, True)
+
+
+@pytest.mark.xfail(reason=PN_LOCAL_BACKSLASH_XFAIL_REASON, raises=AssertionError)
+def test_escapes_and_query_turtle_prefixed() -> None:
+    graph = cached_graph((TEST_DATA_DIR / "variants/forward_slash.ttl",))
+    _test_escapes_and_query(graph, query_string_prefixed, False)
+
+
+def test_escapes_and_query_jsonld_expanded() -> None:
+    graph = cached_graph((TEST_DATA_DIR / "variants/forward_slash.jsonld",))
+    _test_escapes_and_query(graph, query_string_expanded, True)
+
+
+@pytest.mark.xfail(reason=PN_LOCAL_BACKSLASH_XFAIL_REASON, raises=AssertionError)
+def test_escapes_and_query_jsonld_prefixed() -> None:
+    graph = cached_graph((TEST_DATA_DIR / "variants/forward_slash.jsonld",))
+    _test_escapes_and_query(graph, query_string_prefixed, False)