def test_topological_sort_2(self):
""" Does another basic topological sort work?
"""
pairs = [ (1,2), (1,3), (2,4), (3,4), (5,6), (4,5) ]
result, has_cycles = topological_sort(pairs)
self.assert_(not has_cycles)
self.assertEquals(result, [1, 2, 3, 4, 5, 6])
def test_topological_sort_3(self):
""" Does cycle detection work?
"""
pairs = [ (1,2), (2,3), (3,1) ]
result, has_cycles = topological_sort(pairs)
self.assert_(has_cycles)
