ENH, TST: PR 31332 revisions

* Several more size/elsize related typing fixes in the descriptor source to support the above PR, and to fix a Windows test failure observed there (confirmed locally on Windows box). * Augment `test_gh_31308()` with an additional assertion that is sensitive to the need for some of these source changes.
numpy · tylerjereddy · Apr 25, 2026 · Apr 26, 2026 · Apr 26, 2026 · Apr 27, 2026
commit ae6349549671528ddf7f96b48439373300f7039a
diff --git a/numpy/_core/src/multiarray/descriptor.c b/numpy/_core/src/multiarray/descriptor.c
@@ -364,7 +364,7 @@ _convert_from_tuple(PyObject *obj, int align)
         }
         for (int i=0; i < shape.len; i++) {
             PyTuple_SET_ITEM(newdescr->subarray->shape, i,
-                             PyLong_FromLong((long)shape.ptr[i]));
+                             PyLong_FromSsize_t(shape.ptr[i]));
 
             if (PyTuple_GET_ITEM(newdescr->subarray->shape, i) == NULL) {
                 Py_DECREF(newdescr);
@@ -521,7 +521,7 @@ _convert_from_array_descr(PyObject *obj, int align)
             goto fail;
         }
         PyTuple_SET_ITEM(tup, 0, (PyObject *)conv);
-        PyTuple_SET_ITEM(tup, 1, PyLong_FromLong((long) totalsize));
+        PyTuple_SET_ITEM(tup, 1, PyLong_FromSsize_t(totalsize));
 
         /*
          * Title can be "meta-data".  Only insert it
@@ -642,7 +642,7 @@ _convert_from_list(PyObject *obj, int align)
             }
             maxalign = PyArray_MAX(maxalign, _align);
         }
-        PyObject *size_obj = PyLong_FromLong((long) totalsize);
+        PyObject *size_obj = PyLong_FromSsize_t(totalsize);
         if (!size_obj) {
             Py_DECREF(conv);
             goto fail;
@@ -1156,7 +1156,7 @@ _convert_from_dict(PyObject *obj, int align)
                 goto fail;
             }
 
-            PyTuple_SET_ITEM(tup, 1, PyLong_FromLong(offset));
+            PyTuple_SET_ITEM(tup, 1, PyLong_FromSsize_t(offset));
             /* Flag whether the fields are specified out of order */
             if (offset < totalsize) {
                 has_out_of_order_fields = 1;
@@ -1180,7 +1180,7 @@ _convert_from_dict(PyObject *obj, int align)
             if (align && _align > 1) {
                 totalsize = NPY_NEXT_ALIGNED_OFFSET(totalsize, _align);
             }
-            PyTuple_SET_ITEM(tup, 1, PyLong_FromLong(totalsize));
+            PyTuple_SET_ITEM(tup, 1, PyLong_FromSsize_t(totalsize));
             totalsize += newdescr->elsize;
         }
         if (len == 3) {
@@ -1797,7 +1797,7 @@ _convert_from_str(PyObject *obj, int align)
     }
 
     int check_num = NPY_NOTYPE + 10;
-    int elsize = 0;
+    npy_intp elsize = 0;
     /* A typecode like 'd' */
     if (len == 1) {
         /* Python byte string characters are unsigned */
@@ -1810,7 +1810,7 @@ _convert_from_str(PyObject *obj, int align)
 
         /* Attempt to parse the integer, make sure it's the rest of the string */
         errno = 0;
-        long result = strtol(type + 1, &typeend, 10);
+        npy_intp result = strtol(type + 1, &typeend, 10);
         npy_bool some_parsing_happened = !(type == typeend);
         npy_bool entire_string_consumed = *typeend == '\0';
         npy_bool parsing_succeeded =
@@ -1820,7 +1820,7 @@ _convert_from_str(PyObject *obj, int align)
             goto fail;
         }
 
-        elsize = (int)result;
+        elsize = result;
 
 
         if (parsing_succeeded && typeend - type == len) {
@@ -2820,7 +2820,7 @@ arraydescr_reduce(PyArray_Descr *self, PyObject *NPY_UNUSED(args))
         elsize = -1;
         alignment = -1;
     }
-    PyTuple_SET_ITEM(state, 5, PyLong_FromLong(elsize));
+    PyTuple_SET_ITEM(state, 5, PyLong_FromSsize_t(elsize));
     PyTuple_SET_ITEM(state, 6, PyLong_FromLong(alignment));
     PyTuple_SET_ITEM(state, 7, PyLong_FromUnsignedLongLong(
             self->flags & ~NPY_NOT_TRIVIALLY_COPYABLE));

diff --git a/numpy/_core/tests/test_dtype.py b/numpy/_core/tests/test_dtype.py
@@ -2071,6 +2071,8 @@ def test_signature_dtypes_classes(self, typename: str):
 def test_gh_31308(kind, exp):
     kind_dtype = np.dtype(kind)
     assert kind_dtype.itemsize == exp
+    for name in kind_dtype.names:
+        assert kind_dtype[name].shape[0] > 0
 
 
 @pytest.mark.skipif(not IS_64BIT, reason="test requires 64-bit system")