Function convert_ufunc_arguments

numpy/core/src/umath/ufunc_object.c:946–1093

* Due to the array override, do the actual parameter conversion * only in this step. This function takes the reference objects and * parses them into the desired values. * This function cleans up after itself and NULLs references on error, * however, the caller has to ensure that `out_op[0:nargs]` and `out_whermeask` * are NULL initialized. */

 * are NULL initialized.
 */
static int
convert_ufunc_arguments(PyUFuncObject *ufunc,
        ufunc_full_args full_args, PyArrayObject *out_op[],
        PyArray_DTypeMeta *out_op_DTypes[],
        npy_bool *force_legacy_promotion, npy_bool *allow_legacy_promotion,
        npy_bool *promoting_pyscalars,
        PyObject *order_obj, NPY_ORDER *out_order,
        PyObject *casting_obj, NPY_CASTING *out_casting,
        PyObject *subok_obj, npy_bool *out_subok,
        PyObject *where_obj, PyArrayObject **out_wheremask, /* PyArray of bool */
        PyObject *keepdims_obj, int *out_keepdims)
{
    int nin = ufunc->nin;
    int nout = ufunc->nout;
    int nop = ufunc->nargs;
    PyObject *obj;

    /* Convert and fill in input arguments */
    npy_bool all_scalar = NPY_TRUE;
    npy_bool any_scalar = NPY_FALSE;
    *allow_legacy_promotion = NPY_TRUE;
    *force_legacy_promotion = NPY_FALSE;
    *promoting_pyscalars = NPY_FALSE;
    for (int i = 0; i < nin; i++) {
        obj = PyTuple_GET_ITEM(full_args.in, i);

        if (PyArray_Check(obj)) {
            out_op[i] = (PyArrayObject *)obj;
            Py_INCREF(out_op[i]);
        }
        else {
            /* Convert the input to an array and check for special cases */
            out_op[i] = (PyArrayObject *)PyArray_FromAny(obj, NULL, 0, 0, 0, NULL);
            if (out_op[i] == NULL) {
                goto fail;
            }
        }
        out_op_DTypes[i] = NPY_DTYPE(PyArray_DESCR(out_op[i]));
        Py_INCREF(out_op_DTypes[i]);

        if (!NPY_DT_is_legacy(out_op_DTypes[i])) {
            *allow_legacy_promotion = NPY_FALSE;
            // TODO: A subclass of int, float, complex could reach here and
            //       it should not be flagged as "weak" if it does.
        }
        if (PyArray_NDIM(out_op[i]) == 0) {
            any_scalar = NPY_TRUE;
        }
        else {
            all_scalar = NPY_FALSE;
            continue;
        }

        // TODO: Is this equivalent/better by removing the logic which enforces
        //       that we always use weak promotion in the core?
        if (npy_promotion_state == NPY_USE_LEGACY_PROMOTION) {
            continue;  /* Skip use of special dtypes */
        }