def test_enqueue(items, expected_head):
queue = PriorityQueue()
for item in items:
queue.enqueue(item)
assert len(queue) == len(items)
assert queue.peek() == expected_head
def test_iter():
queue = PriorityQueue()
queue.enqueue("a")
queue.enqueue("c")
queue.enqueue("b")
assert [item for item in queue] == ["c", "b", "a"]
def test_dequeue():
queue = PriorityQueue()
queue.enqueue("a")
queue.enqueue("b")
assert queue.dequeue() == "b"
assert len(queue) == 1
def test_peek():
queue = PriorityQueue()
queue.enqueue("a")
queue.enqueue("b")
assert queue.peek() == "b"
assert len(queue) == 2
def test_enqueue(self):
queue = PriorityQueue()
priority_item_one = PriorityItem("item1", 1)
priority_item_two = PriorityItem("item2", 1)
queue.enqueue(priority_item_one)
queue.enqueue(priority_item_two)
front = queue.front()
assert len(queue) == 2
assert front.value == priority_item_one.value
assert front.priority == priority_item_one.priority
priority_item_three = PriorityItem("item3", 2)
queue.enqueue(priority_item_three)
front = queue.front()
assert len(queue) == 3
assert front.value == priority_item_three.value
assert front.priority == priority_item_three.priority
def test_dequeue(self):
queue = PriorityQueue()
priority_item_one = PriorityItem("item1", 1)
priority_item_two = PriorityItem("item2", 3)
priority_item_three = PriorityItem("item3", 99)
queue.enqueue(priority_item_one)
front_item = queue.front()
assert len(queue) == 1
assert front_item.value == priority_item_one.value
assert front_item.priority == priority_item_one.priority
dequed_value = queue.dequeue()
assert len(queue) == 0
assert dequed_value.value == priority_item_one.value
assert dequed_value.priority == priority_item_one.priority
assert queue.dequeue() == None
queue.enqueue(priority_item_three)
queue.enqueue(priority_item_one)
queue.enqueue(priority_item_two)
assert queue.dequeue().value == priority_item_three.value
assert queue.dequeue().value == priority_item_two.value
assert queue.dequeue().value == priority_item_one.value