graph_test.py 中 test_repeated_edges 的逻辑错误

[weilycoder]

注意一下 graph_test.py 的第 95 行，代码的原意是检查边集是否有重。

但是，由于 Edge 类没有定义 __hash__ 和 __eq__，两个不同的对象永远不会被 set 判定为相等。

我在着手修复这项问题：#143

cyaron/cyaron/tests/graph_test.py

Lines 82 to 96 in c92f60d

	def test_repeated_edges(self):
	graph_size = 20
	for _ in range(20):
	graph = Graph.graph(graph_size, int(graph_size*2), repeated_edges=True)
	edges = [(e.start, e.end) for e in graph.iterate_edges()]
	has_repeated_edges = len(edges) > len(set(edges))
	if has_repeated_edges:
	break
	self.assertTrue(has_repeated_edges)
	for _ in range(10):
	graph = Graph.graph(graph_size, int(graph_size*2), repeated_edges=False)
	edges = list(graph.iterate_edges())
	self.assertEqual(len(edges), len(set(edges)))

cyaron/cyaron/graph.py

Lines 9 to 35 in c92f60d

	class Edge:
	"""Class Edge: A class of the edge in the graph"""
	def __init__(self, u, v, w):
	"""__init__(self, u, v, w) -> None
	Initialize a edge.
	int u -> the start vertex
	int v -> the end vertex
	int w -> the weight.
	"""
	self.start = u
	self.end = v
	self.weight = w
	def __str__(self):
	"""__str__(self) -> str
	Return a string to output the edge. The string contains the start vertex, end vertex and weight(u,v,w) and splits with space.
	"""
	return "%d %d %d" % (self.start, self.end, self.weight)
	@staticmethod
	def unweighted_edge(edge):
	"""unweighted_edge(edge) -> str
	Return a string to output the edge without weight. The string contains the start vertex, end vertex(u,v) and splits with space.
	"""
	return '%d %d' % (edge.start, edge.end)

相关行为参阅：

• object.__eq__
• object.__hash__

[weilycoder]

再注意一下第 86 行，合理猜测写这段代码的人发现 test 老是 fail，然后把 fail 的地方改了