test_graph.py 文件源码

def test_has_cycle_two_vertices_linked():
    a = Vertex(Vertex._make_test_vertex())
    b = Vertex(Vertex._make_test_vertex())
    a.add_edge(Edge(b))
    b.add_edge(Edge(a))
    g = Graph([a, b])
    assert g.has_cycle()