def test_reduce_in_degree(self):
dag = ts.DirectedAcyclicGraph()
dag.add_vertex(name='A')
dag.add_vertex(name='B')
assert dag.vertices[1].in_degree == 0
dag.add_adge('A', 'B')
top_search = ts.TopologicalSort(dag)
assert dag.vertices[1].in_degree == 1
top_search.reduce_in_degree(dag.vertices[0])
assert dag.vertices[1].in_degree == 0
def test_add_adge_no_such_adge(self):
dag = ts.DirectedAcyclicGraph()
with pytest.raises(ValueError):
dag.add_adge('A', 'B')
dag.add_vertex(name='A')
with pytest.raises(ValueError):
dag.add_adge('A', 'B')
with pytest.raises(ValueError):
dag.add_adge('A', 'A')
with pytest.raises(ValueError):
dag.add_adge('B', 'B')
def test_is_cycle_error(self):
dag = ts.DirectedAcyclicGraph()
dag.add_vertex(name='A')
dag.add_vertex(name='B')
dag.add_vertex(name='C')
dag.add_adge('A', 'B')
dag.add_adge('B', 'C')
# test simple cycle
with pytest.raises(ValueError):
dag.add_adge('B', 'A')
# test more complex cycle
with pytest.raises(ValueError):
dag.add_adge('C', 'A')
def test_find_in_degree_zero(self):
dag = ts.DirectedAcyclicGraph()
dag.add_vertex(name='A')
top_search = ts.TopologicalSort(dag)
top_search.find_in_degree_zero()
assert len(top_search.in_degree_zero_queue) == 1
top_search.in_degree_zero_queue.clear()
dag.add_vertex(name='B')
top_search.find_in_degree_zero()
assert len(top_search.in_degree_zero_queue) == 2
top_search.in_degree_zero_queue.clear()
dag.add_adge('A', 'B')
top_search.find_in_degree_zero()
assert len(top_search.in_degree_zero_queue) == 1
def test_find_topology(self, capfd):
dag = ts.DirectedAcyclicGraph()
dag.add_vertex(name='A')
dag.add_vertex(name='B')
dag.add_vertex(name='C')
dag.add_vertex(name='D')
dag.add_vertex(name='E')
dag.add_vertex(name='F')
dag.add_adge('A', 'B')
dag.add_adge('A', 'D')
dag.add_adge('B', 'C')
dag.add_adge('C', 'D')
dag.add_adge('D', 'E')
dag.add_adge('C', 'E')
dag.add_adge('E', 'F')
top_search = ts.TopologicalSort(dag)
top_search.find_topology()
print top_search.sorted_topology
out, err = capfd.readouterr()
assert out == '[A, B, C, D, E, F]\n'
def test_find_vertex_good(self):
dag = ts.DirectedAcyclicGraph()
dag.add_vertex(name='A')
assert dag.find_vertex('A').name == 'A'
def test_add_adge_good(self):
dag = ts.DirectedAcyclicGraph()
dag.add_vertex(name='A')
dag.add_vertex(name='B')
dag.add_adge('A', 'B')
assert dag.vertices[0].adjacency_list.head.cargo.name == 'B'
def test_add_vertex_bad(self):
dag = ts.DirectedAcyclicGraph()
dag.add_vertex(name='A')
with pytest.raises(ValueError):
dag.add_vertex(name='A')
def test_add_vertex_good(self):
dag = ts.DirectedAcyclicGraph()
dag.add_vertex(name='A')
assert dag.vertices[0].name == 'A'
dag.add_vertex(name='B')
assert dag.vertices[1].name == 'B'