Add test for possible future type review using JSON signature

No effects were observed on Make-managed files.

PEP 287, Q&A Question 4, and the ReST Primer provided the syntax
reminders on reSructuredText.

References:
* https://docutils.sourceforge.io/docs/user/rst/quickstart.html#text-styles
* https://peps.python.org/pep-0287/#questions-answers

Signed-off-by: Alex Nelson <[email protected]>

tests/test_json_native_type.py

@@ -0,0 +1,83 @@
+#!/usr/bin/env python3
+
+# Portions of this file contributed by NIST are governed by the
+# following statement:
+#
+# 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 within the United States. 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 module includes tests for JSON-LD RDF-type interpretations of native JSON types.
+"""
+
+import json
+from typing import Union
+
+from rdflib import XSD, Graph, Literal, Namespace
+
+JSON = Union[dict[str, "JSON"], list["JSON"], str, int, bool, float, None]
+
+
+def test_json_float() -> None:
+    """
+    This test demonstrates that JSON-LD has a default interpretation of a JSON float [#jsonld1.1-B.1.3]_, automatically typing as ``xsd:double``.  This happens to differ from CASE's default of ``xsd:decimal``.
+
+    References
+    ==========
+
+    .. [#jsonld1.1-B.1.3] https://www.w3.org/TR/json-ld11/#conversion-of-native-data-types
+    """
+
+    expected_graph = Graph()
+    computed_graph = Graph()
+
+    json_graph: JSON = {
+        "@context": {
+            "ex": "http://example.org/ontology/",
+            "kb": "http://example.org/kb/",
+            "xsd": "http://www.w3.org/2001/XMLSchema#",
+        },
+        "@graph": {
+            "@id": "kb:Thing-1",
+            "ex:property1": {"@type": "xsd:decimal", "@value": "1.234"},
+            "ex:property2": {"@type": "xsd:double", "@value": "2.345"},
+            "ex:property3": {"@type": "xsd:float", "@value": "3.456"},
+            "ex:property4": 4.567,
+        },
+    }
+
+    computed_graph.parse(data=json.dumps(json_graph), format="json-ld")
+
+    ns_ex = Namespace("http://example.org/ontology/")
+    ns_kb = Namespace("http://example.org/kb/")
+    ns_xsd = XSD
+
+    expected_graph.add(
+        (
+            ns_kb["Thing-1"],
+            ns_ex["property1"],
+            Literal("1.234", datatype=ns_xsd.decimal),
+        )
+    )
+    expected_graph.add(
+        (ns_kb["Thing-1"], ns_ex["property2"], Literal("2.345", datatype=ns_xsd.double))
+    )
+    expected_graph.add(
+        (ns_kb["Thing-1"], ns_ex["property3"], Literal("3.456", datatype=ns_xsd.float))
+    )
+    expected_graph.add(
+        (ns_kb["Thing-1"], ns_ex["property4"], Literal("4.567", datatype=ns_xsd.double))
+    )
+
+    expected_triples = [x for x in expected_graph.triples((None, None, None))]
+    computed_triples = [x for x in computed_graph.triples((None, None, None))]
+
+    assert expected_triples == computed_triples