def test_simple_expression(self):
x1, x2 = symbols('x1, x2')
function = Or(x1, x2)
self.assertEquals(function.subs({'x1': False, 'x2': False}), False)
self.assertEquals(function.subs({'x1': True, 'x2': False}), True)
self.assertEquals(function.subs({'x1': False, 'x2': True}), True)
self.assertEquals(function.subs({'x1': True, 'x2': True}), True)
def test_complex_expression(self):
x1, x2, x3 = symbols('x1, x2, x3')
subfunction = And(x2, x3)
function = Or(x1, subfunction, And(x1, x2))
print(function.args[0])
print(function.args)
for combination in itertools.combinations((True, False), 3):
self.assertEquals(function.subs(dict(zip(('x1', 'x2', 'x3'), combination))),
combination[0] or (combination[1] and combination[2]))
