class GraphTest(TestCase):
def setUp(self):
self.graph = Graph()
def test_adding_nodes(self):
self.assertEqual(self.graph._graph, {})
self.graph.add_node('1')
self.assertEqual(self.graph._graph, {'1': {}})
self.graph.add_node('2')
self.assertEqual(self.graph._graph, {'1': {}, '2': {}})
def test_add_duplicate_node(self):
self.graph.add_node('1')
self.assertRaises(DuplicateNodeError, self.graph.add_node, '1')
def test_remove_node(self):
self.graph.add_node('1')
self.graph.remove_node('1')
self.assertEqual(self.graph._graph, {})
def test_remove_non_existing_node(self):
self.assertRaises(NodeNotFound, self.graph.remove_node, '1')
def test_add_edges(self):
self.graph.add_node('1')
self.graph.add_node('2')
self.graph.add_edge(from_node='1', to_node='2', weight=1)
self.assertEqual(self.graph._graph, {'1': {'2': 1}, '2': {}})
self.graph.add_edge(from_node='2', to_node='1', weight=5)
self.assertEqual(self.graph._graph, {'1': {'2': 1}, '2': {'1': 5}})
def test_add_edge_overwrite_existing(self):
self.graph.add_node('1')
self.graph.add_node('2')
self.graph.add_edge(from_node='1', to_node='2', weight=1)
self.graph.add_edge(from_node='1', to_node='2', weight=5)
self.assertEqual(self.graph._graph, {'1': {'2': 5}, '2': {}})
def test_remove_node_with_edge(self):
self.graph.add_node('1')
self.graph.add_node('2')
self.graph.add_edge(from_node='1', to_node='2', weight=1)
self.graph.remove_node('2')
self.assertEqual(self.graph._graph, {'1': {}})
def test_remove_edges(self):
self.graph.add_node('1')
self.graph.add_node('2')
self.graph.add_edge(from_node='1', to_node='2', weight=1)
self.graph.remove_edge(from_node='1', to_node='2')
self.assertEqual(self.graph._graph, {'1': {}, '2': {}})
def test_remove_non_existing_edges(self):
self.graph.add_node('1')
self.graph.add_node('2')
self.assertRaises(EdgeNotFound, self.graph.remove_edge,
from_node='1', to_node='2')
def test_remove_edges_without_node(self):
self.assertRaises(NodeNotFound, self.graph.remove_edge,
from_node='1', to_node='2')
def test_complex_graph(self):
exp_graph = {'A': {'C':2,
'D':6},
'B': {'D':8,
'A':3},
'C': {'D':7,
'E':5},
'D': {'E':-2},
'E': {}}
self.graph.add_node('A')
self.graph.add_node('B')
self.graph.add_node('C')
self.graph.add_node('D')
self.graph.add_node('E')
self.graph.add_edge(from_node='A', to_node='C', weight=2)
self.graph.add_edge(from_node='A', to_node='D', weight=6)
self.graph.add_edge(from_node='B', to_node='A', weight=3)
self.graph.add_edge(from_node='B', to_node='D', weight=8)
self.graph.add_edge(from_node='C', to_node='D', weight=7)
self.graph.add_edge(from_node='C', to_node='E', weight=5)
self.graph.add_edge(from_node='D', to_node='E', weight=-2)
self.assertEqual(self.graph._graph, exp_graph)
def test_from_dict(self):
data = {'A': {'C':2,
'D':6},
'B': {'D':8,
'A':3},
'C': {'D':7,
'E':5},
'D': {'E':-2},
'E': {}}
self.graph.from_dict(data)
self.assertEqual(self.graph._graph, data)
