def test_cyclic(self):
g = Digraph()
g.arc(1, 2)
g.arc(2, 1)
self.assertEqual([], g.roots())
g.arc(3)
self.assertTrue(3 in g)
self.assertEqual([3], g.roots())
def test_traverse(self):
g = Digraph()
g.arc(1, 2)
g.arc(2, 3)
g.arc(3, 6)
g.arc(4)
self.assertEquals([1, 4], g.roots())
self.assertEquals([1, 4, 2, 3, 6], list(g.traverse()))
def test_dups(self):
g = Digraph()
#g.arc(1, 2)
g.arc(3, 1, 2)
g.arc(4, 1, 2, 3)
self.assertEquals([4, 1, 2, 3], list(g.traverse()))
g = Digraph()
g.arc(1, 2)
g.arc(3, 2)
g.arc(4, 2)
g.arc(2, 6)
self.assertEquals([1, 3, 4, 2, 6], list(g.traverse()))
g = Digraph()
g.arc(1, 3)
g.arc(3, 2)
g.arc(4, 2)
g.arc(2, 6)
g.arc(15, 2)
self.assertEquals([1, 4, 15], g.roots())
self.assertEquals([1, 4, 15, 3, 2, 6], list(g.traverse()))
'''
def test_find_roots(self):
g = Digraph([1, 2, 3])
g.arc(3, 4) # arc should create a key for 4
# disconnected graph
g.arc(6, 7)
self.assertEqual([1, 2 , 3, 6], g.roots())
def test_roots(self):
g = Digraph([1, 2, 3])
g.arc(3, 4) # arc should create a key for 4
self.assertEqual([1, 2, 3], list(g.roots()))