Convert .pxi include files to .pxd/.pyx in dpnp/tensor

CHANGELOG.md

@@ -12,8 +12,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 * Changed `dpnp.meshgrid` and `dpnp.tensor.meshgrid` to return a tuple instead of a list, aligning with NumPy 2.5+ behavior and 2025.12 version of the Python array API standard [#2854](https://github.com/IntelPython/dpnp/pull/2854)
-
 * Updated `searchsorted` implementations to align with the 2025.12 array API spec [gh-2902](https://github.com/IntelPython/dpnp/pull/2902)
+* Replaced `.pxi` includes in `dpnp.tensor` with modular `.pxd`/`.pyx` Cython imports [#2913](https://github.com/IntelPython/dpnp/pull/2913)
 
 ### Deprecated
 

dpnp/backend/include/dpnp4pybind11.hpp

@@ -32,9 +32,10 @@
 #include "dpctl4pybind11.hpp"
 
 // Include generated Cython headers for usm_ndarray
-// (struct definition and constants only)
 #include "dpnp/tensor/_usmarray.h"
 #include "dpnp/tensor/_usmarray_api.h"
+// Include usm_ndarray constants (flags, type numbers)
+#include "../../tensor/include/usm_ndarray_constants.h"
 
 #include <array>
 #include <cassert>
@@ -191,7 +192,7 @@ class dpnp_capi
         this->UsmNDArray_MakeSimpleFromPtr_ = UsmNDArray_MakeSimpleFromPtr;
         this->UsmNDArray_MakeFromPtr_ = UsmNDArray_MakeFromPtr;
 
-        // constants
+        // constants from usm_ndarray_constants.h
         this->USM_ARRAY_C_CONTIGUOUS_ = USM_ARRAY_C_CONTIGUOUS;
         this->USM_ARRAY_F_CONTIGUOUS_ = USM_ARRAY_F_CONTIGUOUS;
         this->USM_ARRAY_WRITABLE_ = USM_ARRAY_WRITABLE;

dpnp/tensor/_slicing.pxd

@@ -0,0 +1,42 @@
+# *****************************************************************************
+# Copyright (c) 2026, Intel Corporation
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# - Redistributions of source code must retain the above copyright notice,
+#   this list of conditions and the following disclaimer.
+# - Redistributions in binary form must reproduce the above copyright notice,
+#   this list of conditions and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+# - Neither the name of the copyright holder nor the names of its contributors
+#   may be used to endorse or promote products derived from this software
+#   without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+# THE POSSIBILITY OF SUCH DAMAGE.
+# *****************************************************************************
+
+# distutils: language = c++
+# cython: language_level=3
+
+cdef bint _is_buffer(object o)
+
+cdef Py_ssize_t _slice_len(
+    Py_ssize_t sl_start,
+    Py_ssize_t sl_stop,
+    Py_ssize_t sl_step
+)
+
+cdef bint _is_integral(object x) except *
+
+cdef bint _is_boolean(object x) except *

dpnp/tensor/_slicing.pxi → dpnp/tensor/_slicing.pyx

@@ -26,11 +26,16 @@
 # THE POSSIBILITY OF SUCH DAMAGE.
 # *****************************************************************************
 
+# distutils: language = c++
+# cython: language_level=3
+
 import numbers
 from operator import index
 from cpython.buffer cimport PyObject_CheckBuffer
 from numpy import ndarray
 
+from ._usmarray cimport usm_ndarray
+
 
 cdef bint _is_buffer(object o):
     return PyObject_CheckBuffer(o)

dpnp/tensor/_stride_utils.pxd

@@ -0,0 +1,59 @@
+# *****************************************************************************
+# Copyright (c) 2026, Intel Corporation
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# - Redistributions of source code must retain the above copyright notice,
+#   this list of conditions and the following disclaimer.
+# - Redistributions in binary form must reproduce the above copyright notice,
+#   this list of conditions and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+# - Neither the name of the copyright holder nor the names of its contributors
+#   may be used to endorse or promote products derived from this software
+#   without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+# THE POSSIBILITY OF SUCH DAMAGE.
+# *****************************************************************************
+
+# distutils: language = c++
+# cython: language_level=3
+
+cdef extern from "usm_ndarray_constants.h":
+    int USM_ARRAY_C_CONTIGUOUS
+    int USM_ARRAY_F_CONTIGUOUS
+    int USM_ARRAY_WRITABLE
+
+cdef int ERROR_MALLOC
+cdef int ERROR_INTERNAL
+cdef int ERROR_INCORRECT_ORDER
+cdef int ERROR_UNEXPECTED_STRIDES
+
+cdef Py_ssize_t shape_to_elem_count(int nd, Py_ssize_t *shape_arr)
+
+cdef int _from_input_shape_strides(
+    int nd, object shape, object strides, int itemsize, char order,
+    Py_ssize_t **shape_ptr, Py_ssize_t **strides_ptr,
+    Py_ssize_t *nelems, Py_ssize_t *min_disp, Py_ssize_t *max_disp,
+    int *contig
+)
+
+cdef object _make_int_tuple(int nd, const Py_ssize_t *ary)
+
+cdef object _make_reversed_int_tuple(int nd, const Py_ssize_t *ary)
+
+cdef object _c_contig_strides(int nd, Py_ssize_t *shape)
+
+cdef object _f_contig_strides(int nd, Py_ssize_t *shape)
+
+cdef object _swap_last_two(tuple t)

dpnp/tensor/_stride_utils.pxi → dpnp/tensor/_stride_utils.pyx

@@ -29,7 +29,7 @@
 # distutils: language = c++
 # cython: language_level=3
 
-from cpython.mem cimport PyMem_Malloc
+from cpython.mem cimport PyMem_Free, PyMem_Malloc
 from cpython.ref cimport Py_INCREF
 from cpython.tuple cimport PyTuple_New, PyTuple_SetItem
 
@@ -39,10 +39,6 @@ cdef int ERROR_INTERNAL = -1
 cdef int ERROR_INCORRECT_ORDER = 2
 cdef int ERROR_UNEXPECTED_STRIDES = 3
 
-cdef int USM_ARRAY_C_CONTIGUOUS = 1
-cdef int USM_ARRAY_F_CONTIGUOUS = 2
-cdef int USM_ARRAY_WRITABLE = 4
-
 
 cdef Py_ssize_t shape_to_elem_count(int nd, Py_ssize_t *shape_arr):
     """

dpnp/tensor/_types.pxd

@@ -0,0 +1,59 @@
+# *****************************************************************************
+# Copyright (c) 2026, Intel Corporation
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# - Redistributions of source code must retain the above copyright notice,
+#   this list of conditions and the following disclaimer.
+# - Redistributions in binary form must reproduce the above copyright notice,
+#   this list of conditions and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+# - Neither the name of the copyright holder nor the names of its contributors
+#   may be used to endorse or promote products derived from this software
+#   without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+# THE POSSIBILITY OF SUCH DAMAGE.
+# *****************************************************************************
+
+# distutils: language = c++
+# cython: language_level=3
+
+cdef extern from "usm_ndarray_constants.h":
+    int UAR_BOOL
+    int UAR_BYTE
+    int UAR_UBYTE
+    int UAR_SHORT
+    int UAR_USHORT
+    int UAR_INT
+    int UAR_UINT
+    int UAR_LONG
+    int UAR_ULONG
+    int UAR_LONGLONG
+    int UAR_ULONGLONG
+    int UAR_FLOAT
+    int UAR_DOUBLE
+    int UAR_CFLOAT
+    int UAR_CDOUBLE
+    int UAR_TYPE_SENTINEL
+    int UAR_HALF
+
+cdef int type_bytesize(int typenum)
+
+cdef str _make_typestr(int typenum)
+
+cdef int typenum_from_format(str s)
+
+cdef int descr_to_typenum(object dtype)
+
+cdef int dtype_to_typenum(dtype)

dpnp/tensor/_types.pxi → dpnp/tensor/_types.pyx

@@ -26,25 +26,11 @@
 # THE POSSIBILITY OF SUCH DAMAGE.
 # *****************************************************************************
 
-# these typenum values are aligned to values in NumPy
-cdef:
-    int UAR_BOOL = 0  # pragma: no cover
-    int UAR_BYTE = 1  # pragma: no cover
-    int UAR_UBYTE = 2  # pragma: no cover
-    int UAR_SHORT = 3  # pragma: no cover
-    int UAR_USHORT = 4  # pragma: no cover
-    int UAR_INT = 5  # pragma: no cover
-    int UAR_UINT = 6  # pragma: no cover
-    int UAR_LONG = 7  # pragma: no cover
-    int UAR_ULONG = 8  # pragma: no cover
-    int UAR_LONGLONG = 9  # pragma: no cover
-    int UAR_ULONGLONG = 10  # pragma: no cover
-    int UAR_FLOAT = 11  # pragma: no cover
-    int UAR_DOUBLE = 12  # pragma: no cover
-    int UAR_CFLOAT = 14  # pragma: no cover
-    int UAR_CDOUBLE = 15  # pragma: no cover
-    int UAR_TYPE_SENTINEL = 17  # pragma: no cover
-    int UAR_HALF = 23  # pragma: no cover
+# distutils: language = c++
+# cython: language_level=3
+
+import numpy as np
+
 
 cdef int type_bytesize(int typenum):
     """

dpnp/tensor/_usmarray.pxd

@@ -32,27 +32,28 @@
 cimport dpctl
 
 
-cdef public api int USM_ARRAY_C_CONTIGUOUS
-cdef public api int USM_ARRAY_F_CONTIGUOUS
-cdef public api int USM_ARRAY_WRITABLE
+cdef extern from "usm_ndarray_constants.h":
+    int USM_ARRAY_C_CONTIGUOUS
+    int USM_ARRAY_F_CONTIGUOUS
+    int USM_ARRAY_WRITABLE
 
-cdef public api int UAR_BOOL
-cdef public api int UAR_BYTE
-cdef public api int UAR_UBYTE
-cdef public api int UAR_SHORT
-cdef public api int UAR_USHORT
-cdef public api int UAR_INT
-cdef public api int UAR_UINT
-cdef public api int UAR_LONG
-cdef public api int UAR_ULONG
-cdef public api int UAR_LONGLONG
-cdef public api int UAR_ULONGLONG
-cdef public api int UAR_FLOAT
-cdef public api int UAR_DOUBLE
-cdef public api int UAR_CFLOAT
-cdef public api int UAR_CDOUBLE
-cdef public api int UAR_TYPE_SENTINEL
-cdef public api int UAR_HALF
+    int UAR_BOOL
+    int UAR_BYTE
+    int UAR_UBYTE
+    int UAR_SHORT
+    int UAR_USHORT
+    int UAR_INT
+    int UAR_UINT
+    int UAR_LONG
+    int UAR_ULONG
+    int UAR_LONGLONG
+    int UAR_ULONGLONG
+    int UAR_FLOAT
+    int UAR_DOUBLE
+    int UAR_CFLOAT
+    int UAR_CDOUBLE
+    int UAR_TYPE_SENTINEL
+    int UAR_HALF
 
 
 cdef api class usm_ndarray [object PyUSMArrayObject, type PyUSMArrayType]:

dpnp/tensor/_usmarray.pyx

@@ -46,7 +46,6 @@ from ._print import usm_ndarray_repr, usm_ndarray_str
 cimport dpctl as c_dpctl
 cimport dpctl.memory as c_dpmem
 from cpython.mem cimport PyMem_Free
-from cpython.tuple cimport PyTuple_New, PyTuple_SetItem
 
 from . cimport _dlpack as c_dlpack
 
@@ -56,9 +55,35 @@ from . import _flags
 from ._dlpack import get_build_dlpack_version
 from ._tensor_impl import default_device_fp_type
 
-include "_stride_utils.pxi"
-include "_types.pxi"
-include "_slicing.pxi"
+from ._slicing cimport (
+    _is_boolean,
+    _is_buffer,
+    _is_integral,
+    _slice_len,
+)
+
+from ._slicing import _basic_slice_meta
+
+from ._stride_utils cimport (
+    ERROR_INCORRECT_ORDER,
+    ERROR_INTERNAL,
+    ERROR_MALLOC,
+    ERROR_UNEXPECTED_STRIDES,
+    _c_contig_strides,
+    _f_contig_strides,
+    _from_input_shape_strides,
+    _make_int_tuple,
+    _make_reversed_int_tuple,
+    _swap_last_two,
+    shape_to_elem_count,
+)
+from ._types cimport (
+    _make_typestr,
+    descr_to_typenum,
+    dtype_to_typenum,
+    type_bytesize,
+    typenum_from_format,
+)
 
 
 class DLDeviceType(IntEnum):