[3.11] GH-94808: Cover handling non-finite numbers from round when ndigits is provided (GH-94860) (GH-94882)

miss-islington · web-flow · commit e55f60db8f84 · 2022-07-15T10:34:18.000-07:00
(cherry picked from commit 625ba9b) Co-authored-by: Michael Droettboom <mdboom@gmail.com> Automerge-Triggered-By: GH:brandtbucher
diff --git a/Lib/test/test_float.py b/Lib/test/test_float.py
@@ -832,6 +832,11 @@ def test_inf_nan(self):
         self.assertRaises(TypeError, round, NAN, "ceci n'est pas un integer")
         self.assertRaises(TypeError, round, -0.0, 1j)
 
+    def test_inf_nan_ndigits(self):
+        self.assertEqual(round(INF, 0), INF)
+        self.assertEqual(round(-INF, 0), -INF)
+        self.assertTrue(math.isnan(round(NAN, 0)))
+
     def test_large_n(self):
         for n in [324, 325, 400, 2**31-1, 2**31, 2**32, 2**100]:
             self.assertEqual(round(123.456, n), 123.456)
