# test for https://github.com/RDFLib/rdflib/issues/446

from rdflib import Graph, URIRef


def test_sparql_unicode():
    g = Graph()
    trip = (
        URIRef("http://example.org/foo"),
        URIRef("http://example.org/bar"),
        URIRef("http://example.org/jörn"),
    )
    g.add(trip)
    q = 'select ?s ?p ?o where { ?s ?p ?o . FILTER(lang(?o) = "") }'
    r = list(g.query(q))
    assert r == [], "sparql query %r should return nothing but returns %r" % (q, r)


if __name__ == "__main__":
    test_sparql_unicode()
