def test_enqueue_dequeue():
q = BucketPriorityQueue()
q.enqueue(5, 'a')
assert q == BucketPriorityQueue([(5, 'a')])
q.enqueue(4, 'b')
assert q == BucketPriorityQueue([(4, 'b'), (5, 'a')])
assert q.dequeue() == (4, 'b')
assert q == BucketPriorityQueue([(5, 'a')])
assert q.dequeue() == (5, 'a')
assert q == BucketPriorityQueue()
with pytest.raises(ValueError, match='empty'):
_ = q.dequeue()
def test_same_priority_fifo():
a = (5, 'a')
b = (5, 'b')
for x, y in [(a, b), (b, a)]:
q = BucketPriorityQueue()
q.enqueue(*x)
q.enqueue(*y)
assert q
assert q.dequeue() == x
assert q
assert q.dequeue() == y
assert not q
def test_supports_arbitrary_offsets():
m = 1 << 60
q_neg = BucketPriorityQueue()
q_neg.enqueue(-m + 0, 'b')
q_neg.enqueue(-m - 4, 'a')
q_neg.enqueue(-m + 4, 'c')
assert list(q_neg) == [(-m - 4, 'a'), (-m, 'b'), (-m + 4, 'c')]
q_pos = BucketPriorityQueue()
q_pos.enqueue(m + 0, 'b')
q_pos.enqueue(m + 4, 'c')
q_pos.enqueue(m - 4, 'a')
assert list(q_pos) == [(m - 4, 'a'), (m, 'b'), (m + 4, 'c')]
