Improve test coverage for cycles.py (#6152)

* Added test for cycle_basis for graphs with self loops.

* sorted the array for comparision

1 files changed, 9 insertions, 0 deletions

diff --git a/networkx/algorithms/tests/test_cycles.py b/networkx/algorithms/tests/test_cycles.py
index 42a2f017..db62b286 100644
--- a/networkx/algorithms/tests/test_cycles.py
+++ b/networkx/algorithms/tests/test_cycles.py
@@ -50,6 +50,15 @@ class TestCycles:
             G = nx.MultiGraph()
             cy = networkx.cycle_basis(G, 0)
 
+    def test_cycle_basis_self_loop(self):
+        """Tests the function for graphs with self loops"""
+        G = nx.Graph()
+        nx.add_cycle(G, [0, 1, 2, 3])
+        nx.add_cycle(G, [0, 0, 6, 2])
+        cy = nx.cycle_basis(G)
+        sort_cy = sorted(sorted(c) for c in cy)
+        assert sort_cy == [[0], [0, 1, 2], [0, 2, 3], [0, 2, 6]]
+
     def test_simple_cycles(self):
         edges = [(0, 0), (0, 1), (0, 2), (1, 2), (2, 0), (2, 1), (2, 2)]
         G = nx.DiGraph(edges)