Fix the bug described in
http://mail.python.org/pipermail/python-dev/2002-June/025461.html
with test cases.
Also includes extended slice support for arrays, which I thought I'd
already checked in but obviously not.
diff --git a/Modules/arraymodule.c b/Modules/arraymodule.c
index dd93950..c0e59bc 100644
--- a/Modules/arraymodule.c
+++ b/Modules/arraymodule.c
@@ -1478,6 +1478,179 @@
return s;
}
+static PyObject*
+array_subscr(arrayobject* self, PyObject* item)
+{
+ if (PyInt_Check(item)) {
+ long i = PyInt_AS_LONG(item);
+ if (i < 0)
+ i += self->ob_size;
+ return array_item(self, i);
+ }
+ else if (PyLong_Check(item)) {
+ long i = PyLong_AsLong(item);
+ if (i == -1 && PyErr_Occurred())
+ return NULL;
+ if (i < 0)
+ i += self->ob_size;
+ return array_item(self, i);
+ }
+ else if (PySlice_Check(item)) {
+ int start, stop, step, slicelength, cur, i;
+ PyObject* result;
+ arrayobject* ar;
+ int itemsize = self->ob_descr->itemsize;
+
+ if (PySlice_GetIndicesEx((PySliceObject*)item, self->ob_size,
+ &start, &stop, &step, &slicelength) < 0) {
+ return NULL;
+ }
+
+ if (slicelength <= 0) {
+ return newarrayobject(&Arraytype, 0, self->ob_descr);
+ }
+ else {
+ result = newarrayobject(&Arraytype, slicelength, self->ob_descr);
+ if (!result) return NULL;
+
+ ar = (arrayobject*)result;
+
+ for (cur = start, i = 0; i < slicelength;
+ cur += step, i++) {
+ memcpy(ar->ob_item + i*itemsize,
+ self->ob_item + cur*itemsize,
+ itemsize);
+ }
+
+ return result;
+ }
+ }
+ else {
+ PyErr_SetString(PyExc_TypeError,
+ "list indices must be integers");
+ return NULL;
+ }
+}
+
+static int
+array_ass_subscr(arrayobject* self, PyObject* item, PyObject* value)
+{
+ if (PyInt_Check(item)) {
+ long i = PyInt_AS_LONG(item);
+ if (i < 0)
+ i += self->ob_size;
+ return array_ass_item(self, i, value);
+ }
+ else if (PyLong_Check(item)) {
+ long i = PyLong_AsLong(item);
+ if (i == -1 && PyErr_Occurred())
+ return -1;
+ if (i < 0)
+ i += self->ob_size;
+ return array_ass_item(self, i, value);
+ }
+ else if (PySlice_Check(item)) {
+ int start, stop, step, slicelength;
+ int itemsize = self->ob_descr->itemsize;
+
+ if (PySlice_GetIndicesEx((PySliceObject*)item, self->ob_size,
+ &start, &stop, &step, &slicelength) < 0) {
+ return -1;
+ }
+
+ /* treat A[slice(a,b)] = v _exactly_ like A[a:b] = v */
+ if (step == 1 && ((PySliceObject*)item)->step == Py_None)
+ return array_ass_slice(self, start, stop, value);
+
+ if (value == NULL) {
+ /* delete slice */
+ int cur, i;
+
+ if (slicelength <= 0)
+ return 0;
+
+ if (step < 0) {
+ stop = start + 1;
+ start = stop + step*(slicelength - 1) - 1;
+ step = -step;
+ }
+
+ for (cur = start, i = 0; cur < stop;
+ cur += step, i++) {
+ memmove(self->ob_item + (cur - i)*itemsize,
+ self->ob_item + (cur + 1)*itemsize,
+ (step - 1) * itemsize);
+ }
+ if (self->ob_size > (start + slicelength*step)) {
+ memmove(self->ob_item + (start + slicelength*(step - 1))*itemsize,
+ self->ob_item + (start + slicelength*step)*itemsize,
+ (self->ob_size - (start + slicelength*step))*itemsize);
+ }
+
+ self->ob_size -= slicelength;
+ self->ob_item = PyMem_REALLOC(self->ob_item, itemsize*self->ob_size);
+
+
+ return 0;
+ }
+ else {
+ /* assign slice */
+ int cur, i;
+ arrayobject* av;
+
+ if (!array_Check(value)) {
+ PyErr_Format(PyExc_TypeError,
+ "must assign array (not \"%.200s\") to slice",
+ value->ob_type->tp_name);
+ return -1;
+ }
+
+ av = (arrayobject*)value;
+
+ if (av->ob_size != slicelength) {
+ PyErr_Format(PyExc_ValueError,
+ "attempt to assign array of size %d to extended slice of size %d",
+ av->ob_size, slicelength);
+ return -1;
+ }
+
+ if (!slicelength)
+ return 0;
+
+ /* protect against a[::-1] = a */
+ if (self == av) {
+ value = array_slice(av, 0, av->ob_size);
+ av = (arrayobject*)value;
+ }
+ else {
+ Py_INCREF(value);
+ }
+
+ for (cur = start, i = 0; i < slicelength;
+ cur += step, i++) {
+ memcpy(self->ob_item + cur*itemsize,
+ av->ob_item + i*itemsize,
+ itemsize);
+ }
+
+ Py_DECREF(value);
+
+ return 0;
+ }
+ }
+ else {
+ PyErr_SetString(PyExc_TypeError,
+ "list indices must be integers");
+ return -1;
+ }
+}
+
+static PyMappingMethods array_as_mapping = {
+ (inquiry)array_length,
+ (binaryfunc)array_subscr,
+ (objobjargproc)array_ass_subscr
+};
+
static int
array_buffer_getreadbuf(arrayobject *self, int index, const void **ptr)
{
@@ -1699,7 +1872,7 @@
(reprfunc)array_repr, /* tp_repr */
0, /* tp_as _number*/
&array_as_sequence, /* tp_as _sequence*/
- 0, /* tp_as _mapping*/
+ &array_as_mapping, /* tp_as _mapping*/
0, /* tp_hash */
0, /* tp_call */
0, /* tp_str */