def test_del_edge():
graph = DirectedGraph({1: [2]})
assert graph.is_edge(1, 2)
graph.del_edge(1, 2)
assert not graph.is_edge(1, 2)
graph = DirectedGraph({1: [2, 2]})
assert graph.is_edge(1, 2)
graph.del_edge(1, 2)
assert graph.is_edge(1, 2)
graph.del_edge(1, 2)
assert not graph.is_edge(1, 2)
def test_add_edge(self):
d = DirectedGraph()
self.assertFalse(d.is_edge(1, 2))
self.assertEqual(d.get_outdegree(1), 0)
d.add_edge(1, 2)
self.assertEqual(d.get_outdegree(1), 1)
self.assertEqual(d.get_indegree(2), 1)
self.assertTrue(d.is_edge(1, 2))
d.add_edge(1, 2)
self.assertTrue(1, 2)
self.assertEqual(d.get_indegree(2), 1)
def test_add_edge():
graph = DirectedGraph()
assert not graph.is_edge(1, 2)
assert graph.get_outdegree(1) == 0
graph.add_edge(1, 2)
assert graph.get_outdegree(1) == 1
assert graph.get_indegree(2) == 1
assert graph.is_edge(1, 2)
graph.add_edge(1, 2)
assert graph.get_indegree(1) == 0
assert graph.get_outdegree(1) == 2
assert graph.get_indegree(2) == 2
def test_del_edge(self):
d = DirectedGraph({1: [2]})
self.assertTrue(d.is_edge(1, 2))
d.del_edge(1, 2)
self.assertFalse(d.is_edge(1, 2))
def test_is_edge(self):
d = DirectedGraph({1: [2]})
self.assertTrue(d.is_edge(1, 2))
self.assertFalse(d.is_edge(2, 1))
def test_is_edge():
graph = DirectedGraph({1: [2]})
assert graph.is_edge(1, 2)
assert not graph.is_edge(2, 1)