The final tweaks before closing
[ 633152 ] list slice ass ignores subtypes of list
Allow arbitrary sequences on the RHS of extended slices.
diff --git a/Lib/test/test_types.py b/Lib/test/test_types.py
index 1e982d1..106d0a5 100644
--- a/Lib/test/test_types.py
+++ b/Lib/test/test_types.py
@@ -430,6 +430,10 @@
c[2:3:] = ["two", "elements"]
vereq(a, b)
vereq(a, c)
+a = range(10)
+a[::2] = tuple(range(5))
+vereq(a, [0, 1, 1, 3, 2, 5, 3, 7, 4, 9])
+
print '6.6 Mappings == Dictionaries'
d = {}
diff --git a/Objects/listobject.c b/Objects/listobject.c
index 3e3b4d7..25372d3 100644
--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -2238,33 +2238,36 @@
}
else {
/* assign slice */
- PyObject **garbage, *ins;
+ PyObject **garbage, *ins, *seq;
int cur, i;
- if (!PyList_Check(value)) {
- PyErr_Format(PyExc_TypeError,
- "must assign list (not \"%.200s\") to slice",
- value->ob_type->tp_name);
- return -1;
- }
-
- if (PyList_GET_SIZE(value) != slicelength) {
- PyErr_Format(PyExc_ValueError,
- "attempt to assign list of size %d to extended slice of size %d",
- PyList_Size(value), slicelength);
- return -1;
- }
-
- if (!slicelength)
- return 0;
-
/* protect against a[::-1] = a */
if (self == (PyListObject*)value) {
- value = list_slice((PyListObject*)value, 0,
+ seq = list_slice((PyListObject*)value, 0,
PyList_GET_SIZE(value));
}
else {
- Py_INCREF(value);
+ char msg[256];
+ PyOS_snprintf(msg, sizeof(msg),
+ "must assign sequence (not \"%.200s\") to extended slice",
+ value->ob_type->tp_name);
+ seq = PySequence_Fast(value, msg);
+ if (!seq)
+ return -1;
+ }
+
+ if (PySequence_Fast_GET_SIZE(seq) != slicelength) {
+ PyErr_Format(PyExc_ValueError,
+ "attempt to assign sequence of size %d to extended slice of size %d",
+ PySequence_Fast_GET_SIZE(seq),
+ slicelength);
+ Py_DECREF(seq);
+ return -1;
+ }
+
+ if (!slicelength) {
+ Py_DECREF(seq);
+ return 0;
}
garbage = (PyObject**)
@@ -2274,7 +2277,7 @@
cur += step, i++) {
garbage[i] = PyList_GET_ITEM(self, cur);
- ins = PyList_GET_ITEM(value, i);
+ ins = PySequence_Fast_GET_ITEM(seq, i);
Py_INCREF(ins);
PyList_SET_ITEM(self, cur, ins);
}
@@ -2284,7 +2287,7 @@
}
PyMem_FREE(garbage);
- Py_DECREF(value);
+ Py_DECREF(seq);
return 0;
}