class TestVariable(unittest.TestCase):
def setUp(self):
self.v = Variable("1")
self.a = Assignment(1, self.v, True, Clause(Literal(self.v)))
def test_repr(self):
v = Variable("somename")
self.assertEqual(str(v), "somename")
def test_value(self):
#v starts unassigned
self.assertEqual(self.v.value(), None)
#associate v
self.v.assign(self.a)
#v should be assigned true
self.assertTrue(self.v.value())
#disassociate v
self.v.unassign()
#v should be unassigned
self.assertFalse(self.v.isAssigned())
class TestLiteral(unittest.TestCase):
def setUp(self):
self.v1 = Variable("1")
self.v2 = Variable("2")
self.l1 = Literal(self.v1)
self.l2 = Literal(self.v2)
self.l3 = Literal(self.v1, False)
self.a = Assignment(1, self.v2, True, Clause(self.l2))
self.v2.assign(self.a)
def test_eq(self):
t = Literal(self.v1)
self.assertEqual(t, self.l1)
self.assertNotEqual(self.l1, self.l3)
self.assertNotEqual(self.l1, self.l2)
def test_neg(self):
self.assertEqual(self.l3, -self.l1)
def test_value(self):
self.assertTrue(self.l2.value())
class TestClause(unittest.TestCase):
def setUp(self):
self.v1 = Variable("1")
self.v2 = Variable("2")
self.v3 = Variable("3")
self.l1 = Literal(self.v1)
self.l2 = Literal(self.v2)
self.l3 = Literal(self.v2, False)
self.a1 = Assignment(1, self.v2, True, Clause(self.l2))
self.v2.assign(self.a1)
def test_init(self):
c = Clause()
self.assertFalse(hasattr(c, 'revA') or hasattr(c, 'revB'))
c = Clause(Literal(self.v1, True))
self.assertFalse(hasattr(c, 'revA') or hasattr(c, 'revB'))
def test_eq(self):
c1 = Clause(self.l1)
c2 = Clause(self.l2)
c3 = Clause(self.l1)
self.assertEqual(c1, c3)
self.assertNotEqual(c1, c2)
def test_contains(self):
c1 = Clause(self.l1)
c2 = Clause(self.l2)
self.assertTrue(self.l1 in c1)
self.assertFalse(self.l1 in c2)
def test_status(self):
#empty clause
c = Clause()
self.assertEqual(c.status(), "UNSAT")
#single literal
# unassigned
c = Clause(self.l1)
self.assertEqual(c.status(), "UNIT")
# sat
c = Clause(self.l2)
self.assertEqual(c.status(), "SAT")
# unsat
c = Clause(self.l3)
self.assertEqual(c.status(), "UNSAT")
#two-literal
# unit
c = Clause(self.l1, self.l3)
self.assertEqual(c.status(), "UNIT")
# sat
c = Clause(self.l2, self.l3)
self.assertEqual(c.status(), "SAT")
c = Clause(self.l1, self.l2)
self.assertEqual(c.status(), "SAT")
# unsat
c = Clause(self.l3, self.l3)
self.assertEqual(c.status(), "UNSAT")
#multi-literal
# c = Clause(self.l3, self.l1, self.l3)
# self.assertEqual(c.status(),"UNIT")
c = Clause(self.l3, self.l1, self.l1)
self.l3.occurrence_link(c)
self.assertEqual(c.status(), "UNRESOLVED")
c = Clause(self.l3, self.l1, self.l2)
c.link()
self.assertEqual(c.status(), "SAT")
def test_resolution(self):
c1 = Clause(self.l1, self.l2)
c2 = Clause(self.l1, self.l3)
c3 = c1.resolve(c2)
self.assertEqual(c3, Clause(self.l1))