Issue #27443: __length_hint__() of bytearray itearator no longer return
negative integer for resized bytearray.
diff --git a/Lib/test/test_bytes.py b/Lib/test/test_bytes.py
index 9d878ca..05dc26a 100644
--- a/Lib/test/test_bytes.py
+++ b/Lib/test/test_bytes.py
@@ -1328,6 +1328,16 @@
test_exhausted_iterator = test.list_tests.CommonTest.test_exhausted_iterator
+ def test_iterator_length_hint(self):
+ # Issue 27443: __length_hint__ can return negative integer
+ ba = bytearray(b'ab')
+ it = iter(ba)
+ next(it)
+ ba.clear()
+ # Shouldn't raise an error
+ self.assertEqual(list(it), [])
+
+
class AssortedBytesTest(unittest.TestCase):
#
# Test various combinations of bytes and bytearray
diff --git a/Misc/NEWS b/Misc/NEWS
index 7dc5887..014ac54 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -10,6 +10,9 @@
Core and Builtins
-----------------
+- Issue #27443: __length_hint__() of bytearray itearator no longer return
+ negative integer for resized bytearray.
+
- Issue #27007: The fromhex() class methods of bytes and bytearray subclasses
now return an instance of corresponding subclass.
diff --git a/Objects/bytearrayobject.c b/Objects/bytearrayobject.c
index 85990e0..50da637 100644
--- a/Objects/bytearrayobject.c
+++ b/Objects/bytearrayobject.c
@@ -2303,8 +2303,12 @@
bytearrayiter_length_hint(bytesiterobject *it)
{
Py_ssize_t len = 0;
- if (it->it_seq)
+ if (it->it_seq) {
len = PyByteArray_GET_SIZE(it->it_seq) - it->it_index;
+ if (len < 0) {
+ len = 0;
+ }
+ }
return PyLong_FromSsize_t(len);
}