class TestQueue(unittest.TestCase):
def setUp(self):
self.queue = Queue()
self.queue.enqueue(1)
self.queue.enqueue(2)
self.queue.enqueue(3)
self.empty_queue = Queue()
def test_dequeue(self):
assert self.queue.dequeue() == 1
assert self.queue.dequeue() == 2
assert self.queue.dequeue() == 3
assert_raises(IndexError, self.queue.dequeue)
def test_enqueue(self):
self.queue.enqueue(7)
assert len(self.queue) == 4
def test_is_empty(self):
assert self.empty_queue.is_empty()
def test_peek(self):
assert self.queue.peek() == self.queue.peek()
assert self.queue.peek() == 1
assert len(self.queue) == 3
assert_raises(IndexError, self.empty_queue.peek)
def from_array(cls, a: List) -> 'BinaryNode':
"""
Return a complete binary tree from an array
"""
if not a:
return None
# Push first element as root on the queue
q = Queue()
root_node = cls(a[0])
q.enqueue(root_node)
#
for i in a[1:]:
node = cls(i)
parent = q.peek()
if not parent.lnode:
parent.lnode = node
q.enqueue(node)
else:
parent.rnode = node
q.enqueue(node)
q.dequeue()
return root_node
