def test_testMultiLayeredNegation():
program = [
p() <= ~q(),
q() <= ~r(),
r() <= ~s(),
]
assert match_relations(program, p(), [p()])
def test_testNegatedAtomFirst():
n = relation("n")
e = relation("e")
unreach = relation("unreach")
program = [
n(a),
n(b),
n(c),
e(a, b),
e(b, c),
r(X, Y) <= e(X, Y),
r(X, Y) <= [e(X, Z), r(Z, Y)],
unreach(X, Y) <= [~r(X, Y), n(X), n(Y)],
]
assert match_relations(
program,
unreach(X, Y),
[
unreach(b, a),
unreach(c, b),
unreach(c, a),
unreach(a, a),
unreach(b, b),
unreach(c, c),
],
)
def test_queryZeroAryPredicates():
program = [p() <= q(), r() <= [p(), s()], q(), s()]
ans = match_relations(program)
assert ans(q(), [q()])
assert ans(p(), [p()])
assert ans(s(), [s()])
assert ans(r(), [r()])
def test_testRulesWithNoVariables():
program = [p() <= q("a", "b"), q("a", "b")]
ans = match_relations(program)
assert ans(p(), [p()])
program = [p() <= [q("a", "b"), r("c", "d")], q("a", "b"), r("c", "d")]
ans = match_relations(program)
assert ans(p(), [p()])
def test_querymutuallyrecursivepredicates():
program = [
p(X, Y, Z) <= q(X, Y, Z),
q(X, Y, Z) <= p(Z, Y, X),
p(X, Y, Z) <= r(X, Y, Z),
r("a", "b", "c"),
]
ans = match_relations(program)
assert ans(p(X, Y, Z), [p("a", "b", "c"), p("c", "b", "a")])
assert ans(p(X, "b", Y), [p("a", "b", "c"), p("c", "b", "a")])
assert ans(p("a", X, "c"), [p("a", "b", "c")])
assert ans(p(X, "c", Y), [])
def testRulesWithAnonymousVariables():
or_ = relation("or")
on = relation("on")
L, L1 = variables("L", "L1")
a = "a"
b = "b"
c = "c"
d = "d"
program = [
on(L) <= [or_(L, L1, _), on(L1)],
on(L) <= [or_(L, _, L1), on(L1)],
or_(a, b, c),
on(b),
]
ans = match_relations(program)
assert ans(on(a), [on(a)])
assert ans(on(_), [on(a), on(b)])
program = [p() <= [q(_, _), r(_, _)], q(a, b), r(c, d)]
ans = match_relations(program)
assert ans(p(), [p()])
def test_testNegatedUnboundVariable3():
with pytest.raises(DatalogValidationException):
match_relations([p() <= [~q(X, a), ~r(X)]], p(), [])
def test_queryIDBPredicateWithExplicitIDBFact():
# // Note that q is defined by a rule, but we also give an explicit fact.
db = facts([r("a", "b"), q("b", "c")])
rules = [q(X, Y) <= r(X, Y)]
ans = match3(db, rules)
ans(q(X, Y), [(a, b), (b, c)])
def test_queryIDBPredicateWithUndefinedEDB():
db = facts([r("a", "b")])
rules = [q(X, Y) <= p(X, Y)]
ans = match3(db, rules)
ans(q(X, Y), [])