def test_insert_after_node(self):
linked_list = LinkedList2()
n1 = Node(1)
n2 = Node(2)
n3 = Node(3)
n4 = Node(4)
n5 = Node(5)
# inserting into empty list
linked_list.insert(None, n1)
assert linked_list.head == n1
assert linked_list.tail == n1
linked_list.add_in_tail(n2)
linked_list.add_in_tail(n3)
# inserting into list middle
linked_list.insert(n1, n4)
assert n1.next == n4
assert n2.prev == n4
assert n4.prev == n1
assert n4.next == n2
# inserting into tail:
linked_list.insert(n3, n5)
assert n3.next == n5
assert n5.next is None
assert n5.prev == n3
assert linked_list.tail == n5
def test_clean(self):
linked_list = LinkedList2()
linked_list.add_in_tail(Node(1))
linked_list.add_in_tail(Node(2))
linked_list.add_in_tail(Node(3))
linked_list.add_in_tail(Node(4))
linked_list.clean()
assert linked_list.head is None
assert linked_list.tail is None
def test_find_value(self):
linked_list = LinkedList2()
n1 = Node(1)
n2 = Node(2)
n3 = Node(2)
assert linked_list.find(1) is None
linked_list.add_in_tail(n1)
linked_list.add_in_tail(n2)
linked_list.add_in_tail(n3)
assert linked_list.find(1) == n1
def test_find_all_values(self):
linked_list = LinkedList2()
n1 = Node(1)
n2 = Node(2)
n3 = Node(2)
assert len(linked_list.find_all(1)) == 0
linked_list.add_in_tail(n1)
linked_list.add_in_tail(n2)
linked_list.add_in_tail(n3)
# find uniq value
search_result = linked_list.find_all(1)
assert len(search_result) == 1 and search_result[0] == n1
# find repeating values
search_result = linked_list.find_all(2)
assert len(search_result) == 2 and search_result[0] == n2 and search_result[1] == n3
def test_length(self):
list_length = 4
linked_list = LinkedList2()
assert linked_list.len() == 0
for i in range(list_length):
linked_list.add_in_tail(Node(1))
assert linked_list.len() == list_length
def test_add_in_head(self):
linked_list = LinkedList2()
n1 = Node(1)
n2 = Node(2)
# add in empty list
linked_list.add_in_head(n1)
assert linked_list.head == n1
assert linked_list.tail == n1
# add in non empty list
linked_list.add_in_head(n2)
assert linked_list.head == n2
assert linked_list.tail == n1
assert n1.next is None
assert n2.prev is None
assert n1.prev is n2
assert n2.next is n1
def test_deleting_single_value(self):
linked_list = LinkedList2()
linked_list.delete(0)
assert linked_list.head is None
assert linked_list.tail is None
# single-element list
linked_list.add_in_tail(Node(1))
linked_list.delete(1)
assert linked_list.len() == 0
assert linked_list.head is None
assert linked_list.tail is None
# multi-element list
n1 = Node(1)
n2 = Node(1)
n3 = Node(2)
n4 = Node(3)
n5 = Node(4)
linked_list.add_in_tail(n1)
linked_list.add_in_tail(n2)
linked_list.add_in_tail(n3)
linked_list.add_in_tail(n4)
linked_list.add_in_tail(n5)
# deleting head value
linked_list.delete(1)
assert linked_list.head == n2
assert n2.prev is None
assert n2.next == n3
assert n3.prev == n2
assert linked_list.tail == n5
assert linked_list.len() == 4
# deleting tail value
linked_list.delete(4)
assert linked_list.head == n2
assert linked_list.tail == n4
assert n4.next is None
assert n4.prev == n3
assert linked_list.len() == 3
# deleting middle value
linked_list.delete(2)
assert linked_list.head == n2
assert linked_list.tail == n4
assert n2.next == n4
assert n4.prev == n2
assert linked_list.len() == 2
def create_list(self, source):
res = LinkedList2()
for value in source:
res.add_in_tail(Node(value))
return res
self.create_list([1, 2, 3]),
self.create_list([1, 3, 3, 1])
]
results = [0, 1, 2, 3, 4]
for i, c in enumerate(cases):
with self.subTest(case=c):
res = c.len()
self.assertEqual(res, results[i])
def test_insert(self):
cases = [
(self.create_list([1]), 1, 2),
(self.create_list([1, 3]), 1, 2),
(self.create_list([1, 2, 3]), 3, 4),
]
results = [
[1, 2],
[1, 2, 3],
[1, 2, 3, 4],
]
for i, c in enumerate(cases):
with self.subTest(case=c):
list_, index, value = c
node = self.get_node(list_, index)
list_.insert(node, Node(value))
res = self.to_list(list_)
self.assertEqual(res, results[i])
if __name__ == "__main__":
unittest.main()
def test_deleting_all_values(self):
linked_list = LinkedList2()
linked_list.delete(0, True)
assert linked_list.head is None
assert linked_list.tail is None
# single-element list
linked_list.add_in_tail(Node(1))
linked_list.delete(1, True)
assert linked_list.len() == 0
assert linked_list.head is None
assert linked_list.tail is None
# multi-element list
n1 = Node(1)
n2 = Node(1)
n3 = Node(2)
n4 = Node(3)
n5 = Node(3)
n6 = Node(4)
n7 = Node(5)
n8 = Node(5)
linked_list.add_in_tail(n1)
linked_list.add_in_tail(n2)
linked_list.add_in_tail(n3)
linked_list.add_in_tail(n4)
linked_list.add_in_tail(n5)
linked_list.add_in_tail(n6)
linked_list.add_in_tail(n7)
linked_list.add_in_tail(n8)
# deleting head value
linked_list.delete(1, True)
assert linked_list.head == n3
assert n3.prev is None
assert n3.next == n4
assert n4.prev == n3
assert linked_list.tail == n8
assert linked_list.len() == 6
# deleting tail value
linked_list.delete(5, True)
assert linked_list.head == n3
assert linked_list.tail == n6
assert n6.next is None
assert n6.prev == n5
assert linked_list.len() == 4
# deleting middle value
linked_list.delete(3, True)
assert linked_list.head == n3
assert linked_list.tail == n6
assert n3.next == n6
assert n6.prev == n3
assert linked_list.len() == 2
# test deleting in list with equal value
linked_list = LinkedList2()
linked_list.add_in_tail(Node(1))
linked_list.add_in_tail(Node(1))
linked_list.add_in_tail(Node(1))
linked_list.delete(1, True)
assert linked_list.len() == 0
assert linked_list.head is None
assert linked_list.tail is None