def test_erase_head():
l = SingleLinkedList()
l.push_front(1)
assert l.head.data == 1
l.erase(0)
assert l.head == None
def test_front():
l = SingleLinkedList()
for i in range(10):
l.push_back(i)
assert 0 == l.front()
l = SingleLinkedList()
for i in range(10):
l.push_front(i)
assert i == l.front()
def test_reverse():
l = SingleLinkedList()
for i in range(5):
l.push_front(i)
l.reverse()
assert l.head.data == 0
assert l.tail.data == 4
assert l.tail.next == None
for i in range(5):
assert l.pop_front() == i
def test_push_front():
l = SingleLinkedList()
l.push_front(1)
assert l.head.data == 1
assert l.tail.data == 1
l.push_front(2)
assert l.head.data == 2
assert l.tail.data == 1
assert l.head.next.data, l.tail.data
l.push_front(3)
assert l.head.data == 3
assert l.head.next.data == 2
