def test_applies_generics_for_multiple_levels(self):
rules = (Rules().specify(1,
('List', 11)).specify(11, 'Int').instance_of(
2, 1).instance_of(3, 1))
expected_types = {
1: ('List', 11),
2: ('List', 11),
3: ('List', 11),
11: 'Int',
}
self.assertEqual(Result(expected_types, {}), rules.infer())
def test_applies_generics_recursively(self):
rules = (Rules().specify(1, ('Pair', 11, 12)).specify(
2, ('Pair', 21, 22)).specify(11, 'Int').specify(
22, 'String').instance_of(1, 2))
expected_types = {
1: ('Pair', 11, 12),
2: ('Pair', 21, 22),
11: 'Int',
12: 'String',
22: 'String',
}
self.assertEqual(Result(expected_types, {}), rules.infer())
def test_allows_multiple_generic_instantiations(self):
rules = (Rules().specify(1, ('List', 11)).specify(
2,
('List', 21)).specify(3, ('List', 31)).specify(21, 'Int').specify(
31, 'String').instance_of(2, 1).instance_of(3, 1))
expected_types = {
1: ('List', 11),
2: ('List', 21),
3: ('List', 31),
21: 'Int',
31: 'String',
}
self.assertEqual(Result(expected_types, {}), rules.infer())
def test_literal(self):
l = Literal('Int', 123)
l_id = l.add_to_rules(self._rules, self._registry)
self.assertEqual(Result({l_id: 'Int'}, {}), self._rules.infer())
def test_polymorphic_variable(self):
self._registry.push_new_scope({'foo': ('var_foo_1', True)})
v = Variable('foo')
v_id = v.add_to_rules(self._rules, self._registry)
self.assertEqual(Result({}, {}), self._rules.infer())
def test_complicated_subs_work(self):
rules = (Rules().specify(1, 'Int').equal(3, 4).equal(1, 5).equal(
1, 2).equal(5, 2).equal(4, 5))
expected = Result({1: 'Int'}, {2: 1, 3: 1, 4: 1, 5: 1})
self.assertEqual(expected, rules.infer())
def test_generics_with_no_types(self):
rules = Rules()
rules.instance_of(1, 2)
self.assertEqual(Result({}, {}), rules.infer())
def test_applies_substitution(self):
self.assertEqual(Result({1: 'Int'}, {2: 1}),
Rules().specify(1, 'Int').equal(1, 2).infer())
self.assertEqual(
Result({1: 'Int'}, {2: 1}),
Rules().specify(1, 'Int').specify(2, 'Int').equal(1, 2).infer())