def test_sort_peer_nodes_no_longer_than_k(self):
"""
Ensure that no more than constants.K contacts are returned from the
sort_peer_nodes function despite a longer list being passed in.
"""
contacts = []
for i in range(512):
contact = PeerNode(2 ** i, "192.168.0.%d" % i, 9999, self.version,
0)
contacts.append(contact)
target_key = long_to_hex(2 ** 256)
result = sort_peer_nodes(contacts, target_key)
self.assertEqual(constants.K, len(result))
def test_sort_peer_nodes(self):
"""
Ensures that the sort_peer_nodes function returns the list ordered in
such a way that the contacts closest to the target key are at the head
of the list.
"""
contacts = []
for i in range(512):
contact = PeerNode(2 ** i, "192.168.0.%d" % i, 9999, self.version,
0)
contacts.append(contact)
target_key = long_to_hex(2 ** 256)
result = sort_peer_nodes(contacts, target_key)
# Ensure results are in the correct order.
def key(node):
return distance(node.network_id, target_key)
sorted_nodes = sorted(result, key=key)
self.assertEqual(sorted_nodes, result)
# Ensure the order is from lowest to highest in terms of distance
distances = [distance(x.network_id, target_key) for x in result]
self.assertEqual(sorted(distances), distances)
