def it_can_construct_from_seq_of_head_body_pairs(self, from_seq_fixture):
head_body_pairs = from_seq_fixture
productions = Productions.from_seq(*head_body_pairs)
ps = productions._productions
for idx, (head, body) in enumerate(head_body_pairs):
production = ps[idx]
assert type(production) is Production
assert production.head is head
assert production.body is body
def it_can_construct_from_seq_of_head_body_pairs(self, from_seq_fixture):
head_body_pairs = from_seq_fixture
productions = Productions.from_seq(*head_body_pairs)
ps = productions._productions
for idx, (head, body) in enumerate(head_body_pairs):
production = ps[idx]
assert type(production) is Production
assert production.head is head
assert production.body is body
def it_raises_on_attempt_to_create_a_new_attribute(self):
productions = Productions(())
with pytest.raises(AttributeError):
productions.new_attr = '9'
def it_can_get_the_productions_for_a_head_symbol(self, getitem_fixture):
production_seq, key, expected_productions = getitem_fixture
productions = Productions(production_seq)
assert list(productions[key]) == expected_productions
def it_raises_on_attempt_to_create_a_new_attribute(self):
productions = Productions(())
with pytest.raises(AttributeError):
productions.new_attr = '9'
