def test_sequencer_cycle(self):
seq = Sequencer()
seq.add('A', 'B')
seq.add('B', 'C')
seq.add('C', 'D')
self.assertEqual(list(seq.get_steps('D')), ['A', 'B', 'C', 'D'])
seq.add('C', 'A')
self.assertEqual(list(seq.get_steps('D')), ['C', 'A', 'B', 'D'])
self.assertFalse(seq.is_step('E'))
self.assertRaises(ValueError, seq.get_steps, 'E')
seq.add_node('E')
self.assertTrue(seq.is_step('E'))
self.assertEqual(list(seq.get_steps('E')), ['E'])
seq.remove_node('E')
self.assertFalse(seq.is_step('E'))
self.assertRaises(ValueError, seq.get_steps, 'E')
seq.remove('C', 'A')
self.assertEqual(list(seq.get_steps('D')), ['A', 'B', 'C', 'D'])
def test_sequencer_cycle(self):
seq = Sequencer()
seq.add('A', 'B')
seq.add('B', 'C')
seq.add('C', 'D')
self.assertEqual(list(seq.get_steps('D')), ['A', 'B', 'C', 'D'])
seq.add('C', 'A')
self.assertEqual(list(seq.get_steps('D')), ['C', 'A', 'B', 'D'])
self.assertFalse(seq.is_step('E'))
self.assertRaises(ValueError, seq.get_steps, 'E')
seq.add_node('E')
self.assertTrue(seq.is_step('E'))
self.assertEqual(list(seq.get_steps('E')), ['E'])
seq.remove_node('E')
self.assertFalse(seq.is_step('E'))
self.assertRaises(ValueError, seq.get_steps, 'E')
seq.remove('C', 'A')
self.assertEqual(list(seq.get_steps('D')), ['A', 'B', 'C', 'D'])
