def test_delete__non_empty_list_multiple_value_exists__ok(self):
alist = LinkedList()
for i in range(1, 4):
alist.insert_at_head(i)
assert str(alist) == "3 -> 2 -> 1 -> None"
alist.delete(2)
assert str(alist) == "3 -> 1 -> None"
def test_search_multivalued_list__value_does_not_exists__return_false(
self):
alist = LinkedList()
for i in range(1, 4):
alist.insert_at_head(i)
assert str(alist) == "3 -> 2 -> 1 -> None"
assert alist.search(4) is False
def test_insert_at_position__position_out_of_range__raises(self):
with pytest.raises(Exception):
alist = LinkedList()
for i in range(1, 4):
alist.insert_at_head(i)
assert str(alist) == "3 -> 2 -> 1 -> None"
alist.insert_at_position("xxx", 3)
def test_insert_at_position__position_equals_tail__ok(self):
alist = LinkedList()
for i in range(1, 4):
alist.insert_at_head(i)
assert str(alist) == "3 -> 2 -> 1 -> None"
data, position = "xxx", 2
alist.insert_at_position(data, position)
assert str(alist) == f"3 -> 2 -> 1 -> xxx -> None"
def test_insert_at_position__position_equals_head__ok(self):
alist = LinkedList()
for i in range(1, 4):
alist.insert_at_head(i)
assert str(alist) == "3 -> 2 -> 1 -> None"
data, position = "xxx", 0
alist.insert_at_position(data, position)
assert alist.get_head().data == data
assert str(alist) == f"xxx -> 3 -> 2 -> 1 -> None"
def test_insert_at_head__non_empty_list__ok(self):
alist = LinkedList(Node("1"))
assert alist.is_empty() is False
assert alist.get_head() is not None
data = 2
alist.insert_at_head(data)
assert alist.is_empty() is False
assert alist.get_head().data == data
assert str(alist) == f"{data} -> 1 -> None"
def test_insert_at_head__empty_list__ok(self):
alist = LinkedList()
assert alist.is_empty() is True
assert alist.get_head() is None
data = 1
alist.insert_at_head(data)
assert alist.is_empty() is False
assert alist.get_head().data == data
assert str(alist) == f"{data} -> None"
def test_delete_at_head__empty_list_with_many_elements__ok(self):
alist = LinkedList()
for i in range(1, 4):
alist.insert_at_head(i)
assert str(alist) == "3 -> 2 -> 1 -> None"
assert alist.get_head().data == 3
alist.delete_at_head()
assert str(alist) == "2 -> 1 -> None"
assert alist.get_head().data == 2