def test_undirected_graph_remove_vertex(self):
""" Remove vertices from an undirected graph """
g = UndirectedGraph()
g.add_vertex(v_val='v0')
g.add_vertex(v_val='v1')
g.add_vertex(v_val='v2')
g.add_edge(('v0', 'v1'))
g.add_edge(('v1', 'v2'))
g.remove_vertex('v0')
self.assertFalse(g.has_vertex('v0'))
self.assertTrue(g.has_vertex('v1'))
self.assertTrue(g.has_vertex('v2'))
self.assertFalse(g.has_edge(('v0', 'v1')))
self.assertFalse(g.has_edge(('v1', 'v0')))
self.assertTrue(g.has_edge(('v1', 'v2')))
g.remove_vertex('v1')
self.assertFalse(g.has_vertex('v0'))
self.assertFalse(g.has_vertex('v1'))
self.assertTrue(g.has_vertex('v2'))
self.assertFalse(g.has_edge(('v0', 'v1')))
self.assertFalse(g.has_edge(('v1', 'v0')))
self.assertFalse(g.has_edge(('v1', 'v2')))
def test_undirected_graph_add_vertex(self):
""" Add vertices to an undirected graph """
g = UndirectedGraph()
v0_val = g.add_vertex(v_val='v0', attrs={'city': 'Modena'})
v1_val = g.add_vertex(v_val='v1')
self.assertEqual(v0_val, 'v0')
self.assertEqual(v1_val, 'v1')
self.assertTrue(g.has_vertex('v0'))
self.assertTrue(g.has_vertex('v1'))
self.assertFalse(g.has_vertex('v2'))
self.assertEqual(g.get_vertex(v0_val).get('city'), 'Modena')
self.assertIsNone(g.get_vertex(v1_val).get('city'))
def test_undirected_graph_iteration(self):
""" Iterate through an undirected graph """
g = UndirectedGraph()
counter = 0
for v in g:
counter += 1
self.assertEqual(counter, 0)
g.add_vertex(v_val='v0')
g.add_vertex(v_val='v1')
g.add_edge(('v0', 'v1'))
for v in g:
counter += 1
self.assertTrue(g.has_vertex(v.val))
self.assertEqual(counter, 2)
