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_delete__empty_list__ok(self):
alist = LinkedList()
assert alist.is_empty() is True
assert alist.get_head() is None
alist.delete(10)
assert alist.is_empty() is True
assert alist.get_head() is None
def test_delete__non_empty_list_value_not_found__ok(self):
alist = LinkedList(Node(1))
assert str(alist) == "1 -> None"
alist.delete(2)
assert str(alist) == "1 -> None"
def test_delete__non_empty_list_single_value_exists__ok(self):
alist = LinkedList(Node(1))
assert str(alist) == "1 -> None"
alist.delete(1)
assert alist.is_empty() is True
assert alist.get_head() is None