# test for https://github.com/RDFLib/rdflib/issues/579

from rdflib import Graph, URIRef, Literal, Namespace
from rdflib.namespace import FOAF, RDF

g = Graph()
g.bind('foaf', FOAF)
n = Namespace("http://myname/")
g.add((n.bob, FOAF.name, Literal('bb')))
# query is successful.
assert len(g.query("select ?n where { ?n foaf:name 'bb' . }")) == 1
# update is not.
g.update("delete where { ?e foaf:name 'ss' .}")
assert len(g) == 1
g.update("delete where { ?e foaf:name 'bb' .}")
assert len(g) == 0

test for #579