def test_topo_sort():
# 1 2
# \ /
# 3
graph = digraph.DirectedGraph()
graph.add_edges_list((1, 3), (2, 3))
assert digraph.topo_sort(graph) == [2, 1, 3]
# 1 2
# \ /
# 3 5
# |/
# 4
graph = digraph.DirectedGraph()
graph.add_edges_list((1, 3), (2, 3), (3, 4), (5, 4))
assert digraph.topo_sort(graph) == [5, 2, 1, 3, 4]
def test_split_connected_graphs():
# 1 - 2 - 3
# 4 - 5 - 6
graph = digraph.DirectedGraph()
graph.add_edges_list((1, 2), (2, 3), (4, 5), (5, 6))
a, b = digraph.split_connected_graphs(graph)
assert set(a.nodes.keys()) == {1, 2, 3}
assert set(b.nodes.keys()) == {4, 5, 6}
def test_format_edges_reprs():
# 1 - 2 - 3
graph = digraph.DirectedGraph()
edges = [(1, 2), (2, 3, ' |> ')]
graph.add_edges_list(*edges)
assert graph.format().splitlines() == [
'1 > 2 |> 3',
]
def test_walk_edges_from_simple_graph():
# 1 - 2 - 3
graph = digraph.DirectedGraph()
edges = [(1, 2), (2, 3)]
graph.add_edges_list(*edges)
for start_node in range(1, 4):
walked_edges = list(graph.walk_edges_from(start_node))
assert len(walked_edges) == 2
assert set(walked_edges) == set(edges)
def test_format_many_on_one():
# 1
# / \
# 2 3
graph = digraph.DirectedGraph()
edges = [(1, 2), (1, 3)]
graph.add_edges_list(*edges)
assert graph.format().splitlines() == [
'1 > 2',
'1 > 3',
]
def test_walk_edges_from_complex_graphs():
# 1 2
# \ /
# 3 5
# |/
# 4
graph = digraph.DirectedGraph()
edges = [(1, 3), (2, 3), (3, 4), (5, 4)]
graph.add_edges_list(*edges)
for start_node in range(1, 6):
walked_edges = list(graph.walk_edges_from(start_node))
assert len(walked_edges) == 4
assert set(walked_edges) == set(edges)
def test_format():
# 1 2
# \ /
# 3 5
# |/
# 4
graph = digraph.DirectedGraph()
edges = [(1, 3), (2, 3), (3, 4), (5, 4)]
graph.add_edges_list(*edges)
assert graph.format().splitlines() == [
'1 > 3 > 4',
'2 > 3',
'5 > 4',
]
def test_walk_edges_from_disconnected_graphs():
# 1 - 2 - 3
# 4 - 5 - 6
graph = digraph.DirectedGraph()
edges_a = [(1, 2), (2, 3)]
edges_b = [(4, 5), (5, 6)]
graph.add_edges_list(*(edges_a + edges_b))
for start_node in range(1, 4):
walked_edges = list(graph.walk_edges_from(start_node))
assert len(walked_edges) == 2
assert set(walked_edges) == set(edges_a)
for start_node in range(4, 7):
walked_edges = list(graph.walk_edges_from(start_node))
assert len(walked_edges) == 2
assert set(graph.walk_edges_from(start_node)) == set(edges_b)
def test_remove_node():
graph = digraph.DirectedGraph()
graph.add_edges_list((1, 3), (2, 3))
graph.remove_node(2)
assert set(graph.iter_edges()) == set([(1, 3)])
assert set(graph.nodes) == set((1, 3))
def test_topo_sort_cyclic_dependency():
graph = digraph.DirectedGraph()
graph.add_edges_list((1, 3), (2, 3), (3, 1))
with pytest.raises(CyclicDependency) as excinfo:
digraph.topo_sort(graph)
assert list(excinfo.value.nodes) == [1, 3]
def test_format_quoted():
graph = digraph.DirectedGraph()
graph.add_edge('foo bar', 'baz')
assert graph.format() == "'foo bar' > baz"