python
diff --git a/‎Lib/test/test_cmath.py‎
Lines changed: 1 addition & 0 deletions b/‎Lib/test/test_cmath.py‎
Lines changed: 1 addition & 0 deletions
@@ -516,6 +516,7 @@ def test_isinf(self):
         self.assertFalse(cmath.isinf(1j))
         self.assertFalse(cmath.isinf(NAN))
         self.assertTrue(cmath.isinf(INF))
+        self.assertTrue(cmath.isinf(-INF))
         self.assertTrue(cmath.isinf(complex(INF, 0)))
         self.assertTrue(cmath.isinf(complex(0, INF)))
         self.assertTrue(cmath.isinf(complex(INF, INF)))