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Diffstat (limited to '.venv/lib/python3.12/site-packages/networkx/algorithms/traversal/tests/test_bfs.py')
| -rw-r--r-- | .venv/lib/python3.12/site-packages/networkx/algorithms/traversal/tests/test_bfs.py | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/networkx/algorithms/traversal/tests/test_bfs.py b/.venv/lib/python3.12/site-packages/networkx/algorithms/traversal/tests/test_bfs.py new file mode 100644 index 00000000..fcfbbc68 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/networkx/algorithms/traversal/tests/test_bfs.py @@ -0,0 +1,203 @@ +from functools import partial + +import pytest + +import networkx as nx + + +class TestBFS: + @classmethod + def setup_class(cls): + # simple graph + G = nx.Graph() + G.add_edges_from([(0, 1), (1, 2), (1, 3), (2, 4), (3, 4)]) + cls.G = G + + def test_successor(self): + assert dict(nx.bfs_successors(self.G, source=0)) == {0: [1], 1: [2, 3], 2: [4]} + + def test_predecessor(self): + assert dict(nx.bfs_predecessors(self.G, source=0)) == {1: 0, 2: 1, 3: 1, 4: 2} + + def test_bfs_tree(self): + T = nx.bfs_tree(self.G, source=0) + assert sorted(T.nodes()) == sorted(self.G.nodes()) + assert sorted(T.edges()) == [(0, 1), (1, 2), (1, 3), (2, 4)] + + def test_bfs_edges(self): + edges = nx.bfs_edges(self.G, source=0) + assert list(edges) == [(0, 1), (1, 2), (1, 3), (2, 4)] + + def test_bfs_edges_reverse(self): + D = nx.DiGraph() + D.add_edges_from([(0, 1), (1, 2), (1, 3), (2, 4), (3, 4)]) + edges = nx.bfs_edges(D, source=4, reverse=True) + assert list(edges) == [(4, 2), (4, 3), (2, 1), (1, 0)] + + def test_bfs_edges_sorting(self): + D = nx.DiGraph() + D.add_edges_from([(0, 1), (0, 2), (1, 4), (1, 3), (2, 5)]) + sort_desc = partial(sorted, reverse=True) + edges_asc = nx.bfs_edges(D, source=0, sort_neighbors=sorted) + edges_desc = nx.bfs_edges(D, source=0, sort_neighbors=sort_desc) + assert list(edges_asc) == [(0, 1), (0, 2), (1, 3), (1, 4), (2, 5)] + assert list(edges_desc) == [(0, 2), (0, 1), (2, 5), (1, 4), (1, 3)] + + def test_bfs_tree_isolates(self): + G = nx.Graph() + G.add_node(1) + G.add_node(2) + T = nx.bfs_tree(G, source=1) + assert sorted(T.nodes()) == [1] + assert sorted(T.edges()) == [] + + def test_bfs_layers(self): + expected = { + 0: [0], + 1: [1], + 2: [2, 3], + 3: [4], + } + assert dict(enumerate(nx.bfs_layers(self.G, sources=[0]))) == expected + assert dict(enumerate(nx.bfs_layers(self.G, sources=0))) == expected + + def test_bfs_layers_missing_source(self): + with pytest.raises(nx.NetworkXError): + next(nx.bfs_layers(self.G, sources="abc")) + with pytest.raises(nx.NetworkXError): + next(nx.bfs_layers(self.G, sources=["abc"])) + + def test_descendants_at_distance(self): + for distance, descendants in enumerate([{0}, {1}, {2, 3}, {4}]): + assert nx.descendants_at_distance(self.G, 0, distance) == descendants + + def test_descendants_at_distance_missing_source(self): + with pytest.raises(nx.NetworkXError): + nx.descendants_at_distance(self.G, "abc", 0) + + def test_bfs_labeled_edges_directed(self): + D = nx.cycle_graph(5, create_using=nx.DiGraph) + expected = [ + (0, 1, "tree"), + (1, 2, "tree"), + (2, 3, "tree"), + (3, 4, "tree"), + (4, 0, "reverse"), + ] + answer = list(nx.bfs_labeled_edges(D, 0)) + assert expected == answer + + D.add_edge(4, 4) + expected.append((4, 4, "level")) + answer = list(nx.bfs_labeled_edges(D, 0)) + assert expected == answer + + D.add_edge(0, 2) + D.add_edge(1, 5) + D.add_edge(2, 5) + D.remove_edge(4, 4) + expected = [ + (0, 1, "tree"), + (0, 2, "tree"), + (1, 2, "level"), + (1, 5, "tree"), + (2, 3, "tree"), + (2, 5, "forward"), + (3, 4, "tree"), + (4, 0, "reverse"), + ] + answer = list(nx.bfs_labeled_edges(D, 0)) + assert expected == answer + + G = D.to_undirected() + G.add_edge(4, 4) + expected = [ + (0, 1, "tree"), + (0, 2, "tree"), + (0, 4, "tree"), + (1, 2, "level"), + (1, 5, "tree"), + (2, 3, "tree"), + (2, 5, "forward"), + (4, 3, "forward"), + (4, 4, "level"), + ] + answer = list(nx.bfs_labeled_edges(G, 0)) + assert expected == answer + + +class TestBreadthLimitedSearch: + @classmethod + def setup_class(cls): + # a tree + G = nx.Graph() + nx.add_path(G, [0, 1, 2, 3, 4, 5, 6]) + nx.add_path(G, [2, 7, 8, 9, 10]) + cls.G = G + # a disconnected graph + D = nx.Graph() + D.add_edges_from([(0, 1), (2, 3)]) + nx.add_path(D, [2, 7, 8, 9, 10]) + cls.D = D + + def test_limited_bfs_successor(self): + assert dict(nx.bfs_successors(self.G, source=1, depth_limit=3)) == { + 1: [0, 2], + 2: [3, 7], + 3: [4], + 7: [8], + } + result = { + n: sorted(s) for n, s in nx.bfs_successors(self.D, source=7, depth_limit=2) + } + assert result == {8: [9], 2: [3], 7: [2, 8]} + + def test_limited_bfs_predecessor(self): + assert dict(nx.bfs_predecessors(self.G, source=1, depth_limit=3)) == { + 0: 1, + 2: 1, + 3: 2, + 4: 3, + 7: 2, + 8: 7, + } + assert dict(nx.bfs_predecessors(self.D, source=7, depth_limit=2)) == { + 2: 7, + 3: 2, + 8: 7, + 9: 8, + } + + def test_limited_bfs_tree(self): + T = nx.bfs_tree(self.G, source=3, depth_limit=1) + assert sorted(T.edges()) == [(3, 2), (3, 4)] + + def test_limited_bfs_edges(self): + edges = nx.bfs_edges(self.G, source=9, depth_limit=4) + assert list(edges) == [(9, 8), (9, 10), (8, 7), (7, 2), (2, 1), (2, 3)] + + def test_limited_bfs_layers(self): + assert dict(enumerate(nx.bfs_layers(self.G, sources=[0]))) == { + 0: [0], + 1: [1], + 2: [2], + 3: [3, 7], + 4: [4, 8], + 5: [5, 9], + 6: [6, 10], + } + assert dict(enumerate(nx.bfs_layers(self.D, sources=2))) == { + 0: [2], + 1: [3, 7], + 2: [8], + 3: [9], + 4: [10], + } + + def test_limited_descendants_at_distance(self): + for distance, descendants in enumerate( + [{0}, {1}, {2}, {3, 7}, {4, 8}, {5, 9}, {6, 10}] + ): + assert nx.descendants_at_distance(self.G, 0, distance) == descendants + for distance, descendants in enumerate([{2}, {3, 7}, {8}, {9}, {10}]): + assert nx.descendants_at_distance(self.D, 2, distance) == descendants |