def test_undirected_vertex_has_self_edge(self):
""" Get an undirected vertex's has_self_edge property """
v0 = UndirectedVertex(val='v0')
v1 = UndirectedVertex(val='v1')
v2 = UndirectedVertex(val='v2')
e00 = UndirectedEdge((v0, v0))
e01 = UndirectedEdge((v0, v1))
e11 = UndirectedEdge((v1, v1))
e02 = UndirectedEdge((v0, v2))
v0.add_edge(e00)
v0.add_edge(e01)
v1.add_edge(e01)
v0.add_edge(e02)
v2.add_edge(e02)
self.assertTrue(v0.has_self_edge)
self.assertFalse(v1.has_self_edge)
self.assertFalse(v2.has_self_edge)
with self.assertRaises(AttributeError):
v0.has_self_edge = True
v1.add_edge(e11)
v0.remove_edge(e00)
self.assertFalse(v0.has_self_edge)
self.assertTrue(v1.has_self_edge)
self.assertFalse(v2.has_self_edge)
def test_undirected_vertex_remove_edge(self):
""" Remove an edge from an undirected vertex """
v0 = UndirectedVertex(val='v0')
v1 = UndirectedVertex(val='v1')
v2 = UndirectedVertex(val='v2')
e01 = UndirectedEdge((v0, v1))
e10 = UndirectedEdge((v1, v0))
e02 = UndirectedEdge((v0, v2))
v0.add_edge(e01)
v0.add_edge(e02)
v0.remove_edge(e01)
self.assertFalse(e01 in v0)
self.assertFalse(e10 in v0)
self.assertTrue(e02 in v0)
v0.remove_edge(e02)
self.assertFalse(e01 in v0)
self.assertFalse(e10 in v0)
self.assertFalse(e02 in v0)