def test_directed_edge_has_attr(self):
""" Check if a directed edge has a particular attribute """
v0 = DirectedVertex(val='v0')
v1 = DirectedVertex(val='v1')
e01 = DirectedEdge((v0, v1), attrs={'weight': 5, 0: 1})
self.assertTrue(e01.has_attr('weight'))
self.assertFalse(e01.has_attr('length'))
e01.del_attr('weight')
self.assertFalse(e01.has_attr('weight'))
def test_directed_edge_del_attr(self):
""" Delete an attribute of a directed edge """
v0 = DirectedVertex(val='v0')
v1 = DirectedVertex(val='v1')
e01 = DirectedEdge((v0, v1), attrs={'weight': 5, 0: 1})
e01.del_attr('weight')
self.assertEqual(e01.attrs, {0: 1})
e01.del_attr(0)
self.assertEqual(e01.attrs, {})
