diff --git a/Lib/test/test_range.py b/Lib/test/test_range.py index ede07912b0c..4dab448d5a0 100644 --- a/Lib/test/test_range.py +++ b/Lib/test/test_range.py @@ -312,6 +312,15 @@ class RangeTest(unittest.TestCase): self.assertRaises(TypeError, range, IN()) + # Test use of user-defined classes in slice indices. + self.assertEqual(list(range(10)[:I(5)]), list(range(5))) + + with self.assertRaises(RuntimeError): + range(0, 10)[:IX()] + + with self.assertRaises(TypeError): + range(0, 10)[:IN()] + def test_count(self): self.assertEqual(range(3).count(-1), 0) self.assertEqual(range(3).count(0), 1) diff --git a/Misc/NEWS b/Misc/NEWS index 565ebcde8f2..8d6035e1895 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -10,6 +10,9 @@ What's New in Python 3.2.4 Core and Builtins ----------------- +- Issue #16402: When slicing a range, fix shadowing of exceptions from + __index__. + - Issue #16336: fix input checking in the surrogatepass error handler. Patch by Serhiy Storchaka. diff --git a/Objects/rangeobject.c b/Objects/rangeobject.c index b67b9694d58..cebccff9556 100644 --- a/Objects/rangeobject.c +++ b/Objects/rangeobject.c @@ -330,11 +330,11 @@ compute_slice_element(PyObject *obj) if (PyIndex_Check(obj)) { result = PyNumber_Index(obj); } - } - if (result == NULL) { - PyErr_SetString(PyExc_TypeError, - "slice indices must be integers or " - "None or have an __index__ method"); + else { + PyErr_SetString(PyExc_TypeError, + "slice indices must be integers or " + "None or have an __index__ method"); + } } return result; }