diff env/lib/python3.9/site-packages/networkx/algorithms/community/tests/test_kernighan_lin.py @ 0:4f3585e2f14b draft default tip

"planemo upload commit 60cee0fc7c0cda8592644e1aad72851dec82c959"

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/env/lib/python3.9/site-packages/networkx/algorithms/community/tests/test_kernighan_lin.py	Mon Mar 22 18:12:50 2021 +0000
@@ -0,0 +1,59 @@
+"""Unit tests for the :mod:`networkx.algorithms.community.kernighan_lin`
+module.
+
+"""
+import pytest
+
+import networkx as nx
+from networkx.algorithms.community import kernighan_lin_bisection
+from itertools import permutations
+
+
+def assert_partition_equal(x, y):
+    assert set(map(frozenset, x)) == set(map(frozenset, y))
+
+
+def test_partition():
+    G = nx.barbell_graph(3, 0)
+    C = kernighan_lin_bisection(G)
+    assert_partition_equal(C, [{0, 1, 2}, {3, 4, 5}])
+
+
+def test_partition_argument():
+    G = nx.barbell_graph(3, 0)
+    partition = [{0, 1, 2}, {3, 4, 5}]
+    C = kernighan_lin_bisection(G, partition)
+    assert_partition_equal(C, partition)
+
+
+def test_seed_argument():
+    G = nx.barbell_graph(3, 0)
+    C = kernighan_lin_bisection(G, seed=1)
+    assert_partition_equal(C, [{0, 1, 2}, {3, 4, 5}])
+
+
+def test_non_disjoint_partition():
+    with pytest.raises(nx.NetworkXError):
+        G = nx.barbell_graph(3, 0)
+        partition = ({0, 1, 2}, {2, 3, 4, 5})
+        kernighan_lin_bisection(G, partition)
+
+
+def test_too_many_blocks():
+    with pytest.raises(nx.NetworkXError):
+        G = nx.barbell_graph(3, 0)
+        partition = ({0, 1}, {2}, {3, 4, 5})
+        kernighan_lin_bisection(G, partition)
+
+
+def test_multigraph():
+    G = nx.cycle_graph(4)
+    M = nx.MultiGraph(G.edges())
+    M.add_edges_from(G.edges())
+    M.remove_edge(1, 2)
+    for labels in permutations(range(4)):
+        mapping = dict(zip(M, labels))
+        A, B = kernighan_lin_bisection(nx.relabel_nodes(M, mapping), seed=0)
+        assert_partition_equal(
+            [A, B], [{mapping[0], mapping[1]}, {mapping[2], mapping[3]}]
+        )