Triples from the default graph in RDF documents do not go into the default_context of Dataset or ConjunctiveGraph

[aucampia]

I expect data from the default graph in RDF documents to go into the default context/graph of Dataset and ConjunctiveGraph, but they don't.

Given my expectation, this test should pass:

import logging
from typing import Type, Union

import pytest
from pytest_check import check

from rdflib.graph import DATASET_DEFAULT_GRAPH_ID, ConjunctiveGraph, Dataset, Graph
from rdflib.term import BNode, URIRef

RDF_DOCUMENT = """
@prefix egdo: <http://example.org/>.

{
    egdo:gds0 egdo:note "This is a triple inside the default graph." .
}

egdo:gds0 egdo:note "This is an additional note on a triple which is in the default graph." .

egdo:gds1 egdo:note "This is a triple inside the default graph." .

egdo:g0 {
    egdo:g0s0 egdo:note "This is a triple inside a graph named <http://example.org/g0>." .
}

egdo:g1 {
    egdo:g1s0 egdo:note "This is a triple inside a graph named <http://example.org/g1>." .
}
"""


@pytest.mark.parametrize(
    ["container_type"],
    [
        (Dataset,),
        (ConjunctiveGraph,),
    ],
)
def test_issue(container_type: Union[Type[Dataset], Type[ConjunctiveGraph]]) -> None:
    logging.debug("container_type = %s", container_type)
    container = container_type()

    if container_type is Dataset:
        # An empty dataset has 1 default graph and no named graphs, so 1 graph in
        # total.
        with check:
            assert 1 == sum(1 for _ in container.contexts())
        with check:
            assert DATASET_DEFAULT_GRAPH_ID == next((context.identifier for context in container.contexts()), None)
        with check:
            assert container.default_context == next(container.contexts(), None)
    else:
        with check:
            assert isinstance(container.default_context.identifier, BNode)

    # Load an RDF document with triples in three graphs into the dataset.
    container.parse(data=RDF_DOCUMENT, format="trig")

    context_identifiers = set(context.identifier for context in container.contexts())

    logging.info("context_identifiers = %s", context_identifiers)
    logging.info(
        "container.default_context.triples(...) = %s",
        set(container.default_context.triples((None, None, None))),
    )

    all_contexts = set(container.contexts())
    logging.info("all_contexts = %s", (context.identifier for context in all_contexts))

    non_default_contexts = set(container.contexts()) - {container.default_context}
    with check:
        # There should now be two graphs in the container that are not the default graph.
        logging.info("non_default_graphs = %s", (context.identifier for context in non_default_contexts))
        assert 2 == len(non_default_contexts)

    with check:
        # The identifiers of the the non-default graphs should be the ones from the document.
        assert {
            URIRef("http://example.org/g0"),
            URIRef("http://example.org/g1"),
            DATASET_DEFAULT_GRAPH_ID,
        } == set(context.identifier for context in non_default_contexts)

    with check:
        # The default graph should have 3 triples.
        assert 3 == len(container.default_context)

However, when running it against the main branch, it fails:

$ poetry run pytest  --log-level DEBUG '--tb=native' tmp/test_issue.py 
============================================================================ test session starts ============================================================================
platform linux -- Python 3.11.3, pytest-7.3.1, pluggy-1.0.0
rootdir: /home/iwana/sw/d/github.com/iafork/rdflib.change_c
configfile: pyproject.toml
plugins: cov-4.0.0, check-2.1.4
collected 2 items                                                                                                                                                           

tmp/test_issue.py FF                                                                                                                                                  [100%]

================================================================================= FAILURES ==================================================================================
____________________________________________________________________________ test_issue[Dataset] ____________________________________________________________________________
FAILURE: assert 2 == 3
 +  where 3 = len({<Graph identifier=N9153ac77fb8243faac7831b44ec24a62 (<class 'rdflib.graph.Graph'>)>, <Graph identifier=http://example.org/g0 (<class 'rdflib.graph.Graph'>)>, <Graph identifier=http://example.org/g1 (<class 'rdflib.graph.Graph'>)>})
tmp/test_issue.py:70 in test_issue() -> with check:

FAILURE: assert {rdflib.term....lib:default')} == {rdflib.term....mple.org/g1')}
  Extra items in the left set:
  rdflib.term.URIRef('urn:x-rdflib:default')
  Extra items in the right set:
  rdflib.term.BNode('N9153ac77fb8243faac7831b44ec24a62')
  Use -v to get more diff
FAILURE: assert 3 == 0
 +  where 0 = len(<Graph identifier=urn:x-rdflib:default (<class 'rdflib.graph.Graph'>)>)
 +    where <Graph identifier=urn:x-rdflib:default (<class 'rdflib.graph.Graph'>)> = <Graph identifier=N93bafe80e9974e39bd283121bc421bfc (<class 'rdflib.graph.Dataset'>)>.default_context
------------------------------------------------------------
Failed Checks: 3
----------------------------------------------------------------------------- Captured log call -----------------------------------------------------------------------------
2023-05-23T00:06:06.530 DEBUG    root         test_issue.py:39:test_issue container_type = <class 'rdflib.graph.Dataset'>
2023-05-23T00:06:06.533 INFO     root         test_issue.py:60:test_issue context_identifiers = {rdflib.term.BNode('N9153ac77fb8243faac7831b44ec24a62'), rdflib.term.URIRef('urn:x-rdflib:default'), rdflib.term.URIRef('http://example.org/g1'), rdflib.term.URIRef('http://example.org/g0')}
2023-05-23T00:06:06.533 INFO     root         test_issue.py:61:test_issue container.default_context.triples(...) = set()
2023-05-23T00:06:06.533 INFO     root         test_issue.py:67:test_issue all_contexts = <generator object test_issue.<locals>.<genexpr> at 0x7f2f5ddb64d0>
2023-05-23T00:06:06.533 INFO     root         test_issue.py:72:test_issue non_default_graphs = <generator object test_issue.<locals>.<genexpr> at 0x7f2f5ddb6670>
_______________________________________________________________________ test_issue[ConjunctiveGraph] ________________________________________________________________________
FAILURE: assert 2 == 3
 +  where 3 = len({<Graph identifier=N30a66c45d1ed43ae9a77ad56db6701a2 (<class 'rdflib.graph.Graph'>)>, <Graph identifier=http://example.org/g0 (<class 'rdflib.graph.Graph'>)>, <Graph identifier=http://example.org/g1 (<class 'rdflib.graph.Graph'>)>})
tmp/test_issue.py:70 in test_issue() -> with check:

FAILURE: assert {rdflib.term....lib:default')} == {rdflib.term....mple.org/g1')}
  Extra items in the left set:
  rdflib.term.URIRef('urn:x-rdflib:default')
  Extra items in the right set:
  rdflib.term.BNode('N30a66c45d1ed43ae9a77ad56db6701a2')
  Use -v to get more diff
FAILURE: assert 3 == 0
 +  where 0 = len(<Graph identifier=Nab52a9aa38b8413bb5d93ea446c39f47 (<class 'rdflib.graph.Graph'>)>)
 +    where <Graph identifier=Nab52a9aa38b8413bb5d93ea446c39f47 (<class 'rdflib.graph.Graph'>)> = <Graph identifier=N53736eed43af4da9a0b81453e5dace35 (<class 'rdflib.graph.ConjunctiveGraph'>)>.default_context
------------------------------------------------------------
Failed Checks: 3
----------------------------------------------------------------------------- Captured log call -----------------------------------------------------------------------------
2023-05-23T00:06:06.548 DEBUG    root         test_issue.py:39:test_issue container_type = <class 'rdflib.graph.ConjunctiveGraph'>
2023-05-23T00:06:06.548 INFO     root         test_issue.py:60:test_issue context_identifiers = {rdflib.term.BNode('N30a66c45d1ed43ae9a77ad56db6701a2'), rdflib.term.URIRef('http://example.org/g1'), rdflib.term.URIRef('http://example.org/g0')}
2023-05-23T00:06:06.548 INFO     root         test_issue.py:61:test_issue container.default_context.triples(...) = set()
2023-05-23T00:06:06.548 INFO     root         test_issue.py:67:test_issue all_contexts = <generator object test_issue.<locals>.<genexpr> at 0x7f2f5ddb6670>
2023-05-23T00:06:06.548 INFO     root         test_issue.py:72:test_issue non_default_graphs = <generator object test_issue.<locals>.<genexpr> at 0x7f2f5ddb6a80>
========================================================================== short test summary info ==========================================================================
FAILED tmp/test_issue.py::test_issue[Dataset]
FAILED tmp/test_issue.py::test_issue[ConjunctiveGraph]
============================================================================= 2 failed in 0.06s =============================================================================

[aucampia]

These issues are related to this:

• Triples from the default graph in RDF documents do not go into the default_context of Dataset or ConjunctiveGraph #2404
• Dataset adds graph labels where there were none #2375
• Issues with rdflib.Dataset #2021
• rdfpipe adds a graph name to triples in the default graph, consequently breaking round tripping #1804
• ConjunctiveGraph doesn't handle parsing datasets with default graphs properly #436

Also, this blocks resolution of this issue:

• Formats that don't support named graphs serialize Datasets and ConjunctiveGraphs with non-default graphs without raising any errors #2393

[aucampia]

I propose we fix this by changing the parsers to add triples from the default graphs in sources to Dataset.default_context and/or ConjunctiveGraph.default_context.

[aucampia]

Fix is more or less ready, please have a look:

• BREAKING CHANGE: Don't use publicID as the name for the default graph. #2406