def test_graph_one_vertex(self):
g1 = Graph()
print('empty graph= ', g1)
self.assertEqual(str(g1), 'Graph: number of vertices= 0')
v1 = Vertex('Robert')
g1.addVertex(v1)
print(g1)
self.assertEqual(str(g1), 'Graph: number of vertices= 1')
print('number of vertices: {0}'.format(g1.getNumberOfVertices()))
self.assertEqual(g1.getNumberOfVertices(), 1)
print(g1.getLastVertex().getWeight())
self.assertEqual(str(g1.getLastVertex().getWeight()),
'Vertex: vertex= Robert')
print(g1.getVertex(0).getWeight())
self.assertEqual(str(g1.getVertex(0).getWeight()),
'Vertex: vertex= Robert')
def test_graph_two_vertexs(self):
g1 = Graph()
v1 = Vertex('Robert')
v2 = Vertex('Francois')
g1.addVertex(v1)
g1.addVertex(v2)
print('number of vertices: {0}'.format(g1.getNumberOfVertices()))
self.assertEqual(g1.getNumberOfVertices(), 2)
print('number of edges: {0}'.format(g1.getNumberOfEdges()))
self.assertEqual(g1.getNumberOfEdges(), 1)
print(g1.getLastVertex().getWeight())
