def test_remove():
""" Test remove """
l = DoubleLinkedList()
with pytest.raises(LookupError):
l.remove(1)
for i in range(1, 4):
l.append(i)
assert l.remove(2)
assert l.head.value == 1
assert l.head.next.value == 3
assert l.tail.value == 3
assert l._size == 2
def test_double_linked_list():
""" Test list creation and insert method """
l = DoubleLinkedList()
assert l.head == None
assert l.tail == None
assert l._size == 0
for element in [1, 2]:
l.append(element)
print('Value: {}, Type: {}'.format(l.head.value, type(l.head.value)))
assert l.head.value == 1
assert l.tail.value == 2
assert l._size == 2
assert l.head.next.value == 2
assert l.tail.next == None
def test_append():
""" Test append method """
l = DoubleLinkedList()
l.append(1)
assert l.tail.value == 1
assert l.tail.next == None
assert l.head.value == 1
assert l._size == 1
l.append(2)
assert l.tail.value == 2
assert l.tail.next == None
assert l.head.value == 1
assert l.head.next.value == 2
assert l._size == 2
def test_append():
""" Test append method """
l = DoubleLinkedList()
l.append(1)
assert l.tail.value == 1
assert l.tail.next == None
assert l.head.value == 1
assert l._size == 1
l.append(2)
assert l.tail.value == 2
assert l.tail.next == None
assert l.head.value == 1
assert l.head.next.value == 2
assert l._size == 2
def test_double_linked_list():
""" Test list creation and insert method """
l = DoubleLinkedList()
assert l.head == None
assert l.tail == None
assert l._size == 0
for element in [1,2]:
l.append(element)
print('Value: {}, Type: {}'.format(l.head.value, type(l.head.value)))
assert l.head.value == 1
assert l.tail.value == 2
assert l._size == 2
assert l.head.next.value == 2
assert l.tail.next == None
def test_shift():
""" Test shift """
l = DoubleLinkedList()
with pytest.raises(LookupError):
l.shift()
for i in range(1, 4):
l.append(i)
assert l._size == 3
assert l.shift() == 3
assert l.head.value == 1
assert l.tail.value == 2
assert l._size == 2
assert l.shift() == 2
assert l.head.value == 1
assert l.tail.value == 1
assert l._size == 1
def test_shift():
""" Test shift """
l = DoubleLinkedList()
with pytest.raises(LookupError):
l.shift()
for i in range(1,4):
l.append(i)
assert l._size == 3
assert l.shift() == 3
assert l.head.value == 1
assert l.tail.value == 2
assert l._size == 2
assert l.shift() == 2
assert l.head.value == 1
assert l.tail.value == 1
assert l._size == 1
def test_remove():
""" Test remove """
l = DoubleLinkedList()
with pytest.raises(LookupError):
l.remove(1)
for i in range(1,4):
l.append(i)
assert l.remove(2)
assert l.head.value == 1
assert l.head.next.value == 3
assert l.tail.value == 3
assert l._size == 2
class Deque(object):
'''Deque is a composition of Double Linked List'''
def __init__(self, input=None):
'''create doubly linked list'''
self.deque = DoubleLinkedList(input)
def append(self, val):
self.deque.append(val)
def append_left(self, val):
self.deque.insert(val)
def pop(self):
return self.deque.pop()
def pop_left(self):
return self.deque.shift()
def peek(self):
try:
return self.deque.head.data
except AttributeError:
return None
def peek_left(self):
try:
return self.deque.tail.data
except AttributeError:
return None
def size(self):
size = 0
current_spot = self.deque.head
while current_spot:
size += 1
current_spot = current_spot.toward_tail
return size
class Deque(object):
'''Deque is a composition of Double Linked List'''
def __init__(self, input=None):
'''create doubly linked list'''
self.deque = DoubleLinkedList(input)
def append(self, val):
self.deque.append(val)
def append_left(self, val):
self.deque.insert(val)
def pop(self):
return self.deque.pop()
def pop_left(self):
return self.deque.shift()
def peek(self):
try:
return self.deque.head.data
except AttributeError:
return None
def peek_left(self):
try:
return self.deque.tail.data
except AttributeError:
return None
def size(self):
size = 0
current_spot = self.deque.head
while current_spot:
size += 1
current_spot = current_spot.toward_tail
return size
def test_append_list():
from double_linked import DoubleLinkedList
new_list = DoubleLinkedList((4, 5, 65))
new_list.append([45, 'nine', False])
assert new_list.tail.data == [45, 'nine', False]
def test_append_int():
from double_linked import DoubleLinkedList
new_list = DoubleLinkedList((4, 5, 65))
new_list.append(45)
assert new_list.tail.data == 45
def test_append_list():
from double_linked import DoubleLinkedList
new_list = DoubleLinkedList((4, 5, 65))
new_list.append([45, 'nine', False])
assert new_list.tail.data == [45, 'nine', False]
def test_append_int():
from double_linked import DoubleLinkedList
new_list = DoubleLinkedList((4, 5, 65))
new_list.append(45)
assert new_list.tail.data == 45
