def test_testRulesWithBinaryUnifiers():
program = [
tc(X, Y) <= edge(X, Y),
tc(X, Y) <= [edge(X, Z), tc(Z, Y)],
edge(a, b),
edge(b, c),
edge(c, c),
edge(c, d),
cycle(X) <= [eq(X, Y), tc(X, Y)],
beginsAtC(X, Y) <= [tc(X, Y), eq(c, X)],
]
ans = match_relations(program)
assert ans(cycle(X), [cycle(c)])
assert ans(beginsAtC(X, Y), [beginsAtC(c, c), beginsAtC(c, d)])
def test_testBinaryUnificationNoAtom():
program = [
p(X, b) <= eq(X, a),
p(b, Y) <= eq(Y, a),
p(X, Y) <= [eq(X, c), eq(Y, d)],
p(X, X) <= eq(X, c),
p(X, Y) <= [eq(X, d), eq(Y, X)],
p(X, Y) <= [eq(X, Y), eq(X, e)],
]
ans = match_relations(program)
assert ans(p(X, Y), [p(a, b), p(b, a), p(c, d), p(c, c), p(d, d), p(e, e)])
program = program + [q(X, Y) <= p(X, Y)]
ans = match_relations(program)
assert ans(q(X, Y), [q(a, b), q(b, a), q(c, d), q(c, c), q(d, d), q(e, e)])
def test_testNegatedNoPositiveAtom():
program = [p(a) <= ~q(a), p(b) <= [~q(X), eq(X, b)]]
assert match_relations(program, p(X), [p(a), p(b)])
def test_testExplicitUnification1():
program = [p() <= [~q(X, b), eq(X, a)]]
assert match_relations(program, p(), [p()])
def test_testImpossibleBinaryUnification2():
assert match_relations([p() <= [eq(
Z, b), eq(X, Y), eq(a, X), eq(Z, Y)]], p(), [])
def testImpossibleBinaryUnification1():
assert match_relations([p() <= eq(a, b)], p(), [])
def testUselessBinaryUnification():
program = [p(X) <= [q(X), eq(X, Y)], q(a), p(b) <= eq(X, _)]
ans = match_relations(program)
with pytest.raises(DatalogValidationException):
ans(p(X), [])
def test_testImpossibleBinaryDisunification3():
program = [p() <= [q(X), eq(X, X)]]
ans = match_relations(program)
assert ans(p(), [])
def test_testImpossibleBinaryDisunification2():
program = [p() <= [eq(Z, a), not_eq(X, Y), eq(a, X), eq(Z, Y)]]
assert match_relations(program, p(), [])
def test_testBinaryDisunificationNoAtom():
program = [p() <= not_eq(a, b), q() <= [not_eq(X, Y), eq(X, a), eq(Y, b)]]
ans = match_relations(program)
assert ans(p(), [p()])
assert ans(q(), [q()])
