merge 3.2
diff --git a/Modules/_json.c b/Modules/_json.c
index ec980c9..4bc585d 100644
--- a/Modules/_json.c
+++ b/Modules/_json.c
@@ -975,10 +975,11 @@
kind = PyUnicode_KIND(pystr);
length = PyUnicode_GET_LENGTH(pystr);
- if (idx < 0)
- /* Compatibility with Python version. */
- idx += length;
- if (idx < 0 || idx >= length) {
+ if (idx < 0) {
+ PyErr_SetString(PyExc_ValueError, "idx cannot be negative");
+ return NULL;
+ }
+ if (idx >= length) {
PyErr_SetNone(PyExc_StopIteration);
return NULL;
}