def test_simple():
tc = relation("tc")
edge = relation("edge")
program = [tc() <= edge()]
abc_program = convert(program)
strata_str = validate(abc_program)
assert ['{tc}'] == strata_str
def test_no_stratification():
p = relation("p")
q = relation("q")
program = [p() <= ~q(), q() <= ~p()]
abc_program = convert(program)
with pytest.raises(DatalogValidationException):
validate(abc_program)
def test_simple_negated():
p = relation("p")
q = relation("q")
program = [p() <= ~q()]
abc_program = convert(program)
strata_str = validate(abc_program)
assert strata_str == ['{p}']
pass
def test_pq():
p = relation("p")
q = relation('q')
r = relation('r')
program = [p() <= [q(), ~r()], q() <= r(), r() <= q()]
abc_program = convert(program)
strata_str = validate(abc_program)
assert strata_str[-1] == '{p}'
def test_reachable():
X = Variable("X")
Y = Variable("Y")
Z = Variable("Z")
reachable = relation("reachable")
edge = relation("edge")
not_reachable = relation("not_reachable")
node = relation("node")
program = [
reachable(X, Y) <= edge(X, Y),
reachable(X, Y) <= [edge(X, Z), reachable(Z, Y)],
not_reachable(X, Y) <= [node(X), node(Y), ~reachable(X, Y)],
node(X) <= edge(X, _),
node(X) <= edge(_, X)
]
abc_program = convert(program)
sorted_strata_str = validate(abc_program)
exp = ['{reachable}', '{node}', '{not_reachable}']
assert sorted_strata_str[-1] == exp[-1]