fix: restore the 6.1.1 default bound namespaces

The namespaces bound by default by `rdflib.graph.Graph` and
`rdflib.namespace.NamespaceManager` was reduced in version 6.2.0 of RDFLib,
however, this also would cause code that worked with 6.1.1 to break, so this
constituted a breaking change. This change restores the previous behavior,
binding the same namespaces as was bound in 6.1.1.

To bind a reduced set of namespaces the `bind_namespaces` parameter of
`rdflib.graph.Graph` or `rdflib.namespace.NamespaceManager` can be used.

- Closes <#2103>.

rdflib/graph.py

@@ -437,7 +437,7 @@ def __init__(
         identifier: Optional[Union[_ContextIdentifierType, str]] = None,
         namespace_manager: Optional[NamespaceManager] = None,
         base: Optional[str] = None,
-        bind_namespaces: "_NamespaceSetString" = "core",
+        bind_namespaces: "_NamespaceSetString" = "rdflib",
     ):
         super(Graph, self).__init__()
         self.base = base

rdflib/namespace/__init__.py

@@ -360,20 +360,28 @@ class NamespaceManager(object):
     * core:
         * binds several core RDF prefixes only
         * owl, rdf, rdfs, xsd, xml from the NAMESPACE_PREFIXES_CORE object
-        * this is default
     * rdflib:
         * binds all the namespaces shipped with RDFLib as DefinedNamespace instances
         * all the core namespaces and all the following: brick, csvw, dc, dcat
         * dcmitype, dcterms, dcam, doap, foaf, geo, odrl, org, prof, prov, qb, schema
         * sh, skos, sosa, ssn, time, vann, void
         * see the NAMESPACE_PREFIXES_RDFLIB object for the up-to-date list
+        * this is default
     * none:
         * binds no namespaces to prefixes
         * note this is NOT default behaviour
     * cc:
         * using prefix bindings from prefix.cc which is a online prefixes database
         * not implemented yet - this is aspirational
 
+    .. attention::
+
+        The namespaces bound for specific values of ``bind_namespaces``
+        constitute part of RDFLib's public interface, so changes to them should
+        only be additive within the same minor version. Removing values, or
+        removing namespaces that are bound by default, constitutes a breaking
+        change.
+
     See the
     Sample usage
 
@@ -390,10 +398,11 @@ class NamespaceManager(object):
         >>> all_ns = [n for n in g.namespace_manager.namespaces()]
         >>> assert ('ex', rdflib.term.URIRef('http://example.com/')) in all_ns
         >>>
-
     """
 
-    def __init__(self, graph: "Graph", bind_namespaces: "_NamespaceSetString" = "core"):
+    def __init__(
+        self, graph: "Graph", bind_namespaces: "_NamespaceSetString" = "rdflib"
+    ):
         self.graph = graph
         self.__cache: Dict[str, Tuple[str, URIRef, str]] = {}
         self.__cache_strict: Dict[str, Tuple[str, URIRef, str]] = {}

test/test_namespace/test_namespacemanager.py

@@ -33,9 +33,41 @@ def test_core_prefixes_bound():
     g = Graph()
 
     # prefixes in Graph
-    assert len(list(g.namespaces())) == len(_NAMESPACE_PREFIXES_CORE)
+    assert len(list(g.namespaces())) == len(
+        {**_NAMESPACE_PREFIXES_RDFLIB, **_NAMESPACE_PREFIXES_CORE}
+    )
     pre = sorted([x[0] for x in list(g.namespaces())])
-    assert pre == ["owl", "rdf", "rdfs", "xml", "xsd"]
+    assert pre == [
+        "brick",
+        "csvw",
+        "dc",
+        "dcam",
+        "dcat",
+        "dcmitype",
+        "dcterms",
+        "doap",
+        "foaf",
+        "geo",
+        "odrl",
+        "org",
+        "owl",
+        "prof",
+        "prov",
+        "qb",
+        "rdf",
+        "rdfs",
+        "schema",
+        "sh",
+        "skos",
+        "sosa",
+        "ssn",
+        "time",
+        "vann",
+        "void",
+        "wgs",
+        "xml",
+        "xsd",
+    ]
 
 
 def test_rdflib_prefixes_bound():
@@ -175,6 +207,40 @@ def test_nman_bind_namespaces(
 @pytest.mark.parametrize(
     ["selector", "expected_bindings"],
     [
+        (
+            None,
+            {
+                "brick": "https://brickschema.org/schema/Brick#",
+                "csvw": "http://www.w3.org/ns/csvw#",
+                "dc": "http://purl.org/dc/elements/1.1/",
+                "dcat": "http://www.w3.org/ns/dcat#",
+                "dcmitype": "http://purl.org/dc/dcmitype/",
+                "dcterms": "http://purl.org/dc/terms/",
+                "dcam": "http://purl.org/dc/dcam/",
+                "doap": "http://usefulinc.com/ns/doap#",
+                "foaf": "http://xmlns.com/foaf/0.1/",
+                "odrl": "http://www.w3.org/ns/odrl/2/",
+                "geo": "http://www.opengis.net/ont/geosparql#",
+                "org": "http://www.w3.org/ns/org#",
+                "owl": "http://www.w3.org/2002/07/owl#",
+                "prof": "http://www.w3.org/ns/dx/prof/",
+                "prov": "http://www.w3.org/ns/prov#",
+                "qb": "http://purl.org/linked-data/cube#",
+                "rdf": "http://www.w3.org/1999/02/22-rdf-syntax-ns#",
+                "rdfs": "http://www.w3.org/2000/01/rdf-schema#",
+                "schema": "https://schema.org/",
+                "sh": "http://www.w3.org/ns/shacl#",
+                "skos": "http://www.w3.org/2004/02/skos/core#",
+                "sosa": "http://www.w3.org/ns/sosa/",
+                "ssn": "http://www.w3.org/ns/ssn/",
+                "time": "http://www.w3.org/2006/time#",
+                "vann": "http://purl.org/vocab/vann/",
+                "void": "http://rdfs.org/ns/void#",
+                "wgs": "https://www.w3.org/2003/01/geo/wgs84_pos#",
+                "xsd": "http://www.w3.org/2001/XMLSchema#",
+                "xml": "http://www.w3.org/XML/1998/namespace",
+            },
+        ),
         (
             "rdflib",
             {
@@ -208,19 +274,39 @@ def test_nman_bind_namespaces(
                 "xsd": "http://www.w3.org/2001/XMLSchema#",
                 "xml": "http://www.w3.org/XML/1998/namespace",
             },
-        )
+        ),
+        (
+            "core",
+            {
+                "owl": "http://www.w3.org/2002/07/owl#",
+                "rdf": "http://www.w3.org/1999/02/22-rdf-syntax-ns#",
+                "rdfs": "http://www.w3.org/2000/01/rdf-schema#",
+                "xsd": "http://www.w3.org/2001/XMLSchema#",
+                "xml": "http://www.w3.org/XML/1998/namespace",
+            },
+        ),
     ],
 )
 def test_bound_namespaces_subset(
-    selector: Any, expected_bindings: Dict[str, str]
+    selector: Optional[Any], expected_bindings: Dict[str, str]
 ) -> None:
-    graph = Graph(bind_namespaces=selector)
+    if selector is not None:
+        graph = Graph(bind_namespaces=selector)
+    else:
+        graph = Graph()
     bound_namespaces = dict(
         (key, str(value)) for key, value in graph.namespace_manager.namespaces()
     )
     assert (
         expected_bindings.items() <= bound_namespaces.items()
     ), f"missing items {expected_bindings.items() - bound_namespaces.items()}"
+    empty_graph = Graph(bind_namespaces="none")
+    if selector is not None:
+        nman = NamespaceManager(empty_graph, bind_namespaces=selector)
+    else:
+        nman = NamespaceManager(empty_graph)
+    nman_bound_namespaces = dict((key, str(value)) for key, value in nman.namespaces())
+    assert bound_namespaces == nman_bound_namespaces
 
 
 def test_compute_qname_no_generate() -> None: