1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
|
from rdflib import Graph, Literal, URIRef, Variable
def test_binding_with_optional_clause() -> None:
"""
Optional clauses should bind variables if feasible.
See https://github.com/RDFLib/rdflib/issues/2957
"""
g = Graph().parse(
data="""
prefix ex: <https://www.example.org/>
ex:document ex:subject "Nice cars" .
ex:someCar ex:type "Car" .
"""
)
result = g.query(
"""prefix ex: <https://www.example.org/>
select ?subject ?car
where {
$this ex:subject ?subject.
optional
{
# an offending subselect clause
select ?car
where {
?car ex:type "Car".
}
}
}"""
)
assert len(result.bindings) == 1
(first,) = result.bindings
assert first.get(Variable("car")) == URIRef("https://www.example.org/someCar")
assert first.get(Variable("subject")) == Literal(
"Nice cars"
), "optional clause didnt bind"
|
