Do not let overflows in enumerate() and count() pass silently.
diff --git a/Lib/test/test_itertools.py b/Lib/test/test_itertools.py
index 5e375c9..c965d4c 100644
--- a/Lib/test/test_itertools.py
+++ b/Lib/test/test_itertools.py
@@ -52,8 +52,7 @@
self.assertEqual(take(2, zip('abc',count(3))), [('a', 3), ('b', 4)])
self.assertRaises(TypeError, count, 2, 3)
self.assertRaises(TypeError, count, 'a')
- c = count(sys.maxint-2) # verify that rollover doesn't crash
- c.next(); c.next(); c.next(); c.next(); c.next()
+ self.assertRaises(OverflowError, list, islice(count(sys.maxint-5), 10))
c = count(3)
self.assertEqual(repr(c), 'count(3)')
c.next()
diff --git a/Misc/NEWS b/Misc/NEWS
index a24ec26..8f15724 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,8 @@
Core and builtins
-----------------
+- SF #151204: enumerate() now raises an Overflow error at sys.maxint items.
+
- Bug #1377858: Fix the segfaulting of the interpreter when an object created
a weakref on itself during a __del__ call for new-style classes (classic
classes still have the bug).
@@ -103,6 +105,8 @@
Extension Modules
-----------------
+- operator.count() now raises an OverflowError when the count reaches sys.maxint.
+
- Bug #1575169: operator.isSequenceType() now returns False for subclasses of dict.
- collections.defaultdict() now verifies that the factory function is callable.
diff --git a/Modules/itertoolsmodule.c b/Modules/itertoolsmodule.c
index 7896143..70f787f 100644
--- a/Modules/itertoolsmodule.c
+++ b/Modules/itertoolsmodule.c
@@ -2073,6 +2073,11 @@
static PyObject *
count_next(countobject *lz)
{
+ if (lz->cnt == LONG_MAX) {
+ PyErr_SetString(PyExc_OverflowError,
+ "cannot count beyond LONG_MAX");
+ return NULL;
+ }
return PyInt_FromSsize_t(lz->cnt++);
}
diff --git a/Objects/enumobject.c b/Objects/enumobject.c
index a8f43e0..a456c9d 100644
--- a/Objects/enumobject.c
+++ b/Objects/enumobject.c
@@ -62,6 +62,12 @@
PyObject *result = en->en_result;
PyObject *it = en->en_sit;
+ if (en->en_index == LONG_MAX) {
+ PyErr_SetString(PyExc_OverflowError,
+ "enumerate() is limited to LONG_MAX items");
+ return NULL;
+ }
+
next_item = (*it->ob_type->tp_iternext)(it);
if (next_item == NULL)
return NULL;