Fix dominance tests (#1524)

* Fix dominance tests on HEAD

* Flip side of subset

* Fix last incompatible assertion

* Black

Author: IvanIsCoding

tests/digraph/test_dominance.py

@@ -57,7 +57,10 @@ def test_singleton(self):
 
         nx_graph = nx.DiGraph()
         nx_graph.add_edges_from(graph.edge_list())
-        self.assertDictEqual(nx.immediate_dominators(nx_graph, 0), {0: 0})
+        # subset check
+        self.assertGreaterEqual(
+            rx.immediate_dominators(graph, 0).items(), nx.immediate_dominators(nx_graph, 0).items()
+        )
 
     def test_irreducible1(self):
         """
@@ -74,7 +77,8 @@ def test_irreducible1(self):
 
         nx_graph = nx.DiGraph()
         nx_graph.add_edges_from(graph.edge_list())
-        self.assertDictEqual(nx.immediate_dominators(nx_graph, 5), result)
+        # subset check
+        self.assertGreaterEqual(result.items(), nx.immediate_dominators(nx_graph, 5).items())
 
     def test_irreducible2(self):
         """
@@ -91,7 +95,8 @@ def test_irreducible2(self):
 
         nx_graph = nx.DiGraph()
         nx_graph.add_edges_from(graph.edge_list())
-        self.assertDictEqual(nx.immediate_dominators(nx_graph, 6), result)
+        # subset check
+        self.assertGreaterEqual(result.items(), nx.immediate_dominators(nx_graph, 6).items())
 
     def test_domrel_png(self):
         """
@@ -107,14 +112,17 @@ def test_domrel_png(self):
 
         nx_graph = nx.DiGraph()
         nx_graph.add_edges_from(graph.edge_list())
-        self.assertDictEqual(nx.immediate_dominators(nx_graph, 1), result)
+        # subset check
+        self.assertGreaterEqual(result.items(), nx.immediate_dominators(nx_graph, 1).items())
 
         # Test postdominance.
         graph.reverse()
         result = rx.immediate_dominators(graph, 6)
         self.assertDictEqual(result, {1: 2, 2: 6, 3: 5, 4: 5, 5: 2, 6: 6})
-
-        self.assertDictEqual(nx.immediate_dominators(nx_graph.reverse(copy=False), 6), result)
+        # subset check
+        self.assertGreaterEqual(
+            result.items(), nx.immediate_dominators(nx_graph.reverse(copy=False), 6).items()
+        )
 
     def test_boost_example(self):
         """
@@ -129,14 +137,17 @@ def test_boost_example(self):
 
         nx_graph = nx.DiGraph()
         nx_graph.add_edges_from(graph.edge_list())
-        self.assertDictEqual(nx.immediate_dominators(nx_graph, 0), result)
+        # subset check
+        self.assertGreaterEqual(result.items(), nx.immediate_dominators(nx_graph, 0).items())
 
         # Test postdominance.
         graph.reverse()
         result = rx.immediate_dominators(graph, 7)
         self.assertDictEqual(result, {0: 1, 1: 7, 2: 7, 3: 4, 4: 5, 5: 7, 6: 4, 7: 7})
-
-        self.assertDictEqual(nx.immediate_dominators(nx_graph.reverse(copy=False), 7), result)
+        # subset check
+        self.assertGreaterEqual(
+            result.items(), nx.immediate_dominators(nx_graph.reverse(copy=False), 7).items()
+        )
 
 
 class TestDominanceFrontiers(unittest.TestCase):