class NodeParserTests(unittest.TestCase):
def setUp(self):
self.mock = mox.Mox()
self.rpnMock = self.mock.CreateMock(ReversePolishNotationConverter)
self.parser = NodeParser(self.rpnMock)
def parse_expression(self, exp, rpn_exp):
self.rpnMock.transform(exp).AndReturn(rpn_exp)
self.mock.ReplayAll()
tree = self.parser.parse(exp)
return tree
def test_parses_a_plus(self):
tree = self.parse_expression("1+2", "1 2 +")
self.assertEqual(1, tree.left.evaluate())
self.assertEqual(2, tree.right.evaluate())
self.assertEqual(3, tree.evaluate())
def test_parses_a_minus(self):
tree = self.parse_expression("1-2", "1 2 -")
self.assertEqual(1, tree.left.evaluate())
self.assertEqual(2, tree.right.evaluate())
self.assertEqual(-1, tree.evaluate())
def test_parses_a_multiplication(self):
tree = self.parse_expression("2*3", "2 3 *")
self.assertEqual(2, tree.left.evaluate())
self.assertEqual(3, tree.right.evaluate())
self.assertEqual(6, tree.evaluate())
def test_parses_a_division(self):
tree = self.parse_expression("1/2", "1 2 /")
self.assertEqual(1, tree.left.evaluate())
self.assertEqual(2, tree.right.evaluate())
self.assertEqual(0.5, tree.evaluate())
def test_parses_complex_no_brackets(self):
tree = self.parse_expression("1+2/8", "1 2 8 / +")
self.assertEqual(1, tree.left.evaluate())
self.assertEqual(2, tree.right.left.evaluate())
self.assertEqual(8, tree.right.right.evaluate())
self.assertEqual(1.25, tree.evaluate())
def test_parses_complex_with_brackets(self):
tree = self.parse_expression("(2+7)*4", "2 7 + 4 *")
self.assertEqual(2, tree.left.left.evaluate())
self.assertEqual(7, tree.left.right.evaluate())
self.assertEqual(4, tree.right.evaluate())
self.assertEqual(36, tree.evaluate())
def setUp(self):
self.mock = mox.Mox()
self.rpnMock = self.mock.CreateMock(ReversePolishNotationConverter)
self.parser = NodeParser(self.rpnMock)
