More xp scipy

.gitlab-ci.yml

@@ -3,6 +3,8 @@ variables:
   PIP_DISABLE_PIP_VERSION_CHECK: "1"
   CUNUMPY_BACKEND: "cupy"
   CUNUMPY_REQUIRE_CUDA: "1"
+  # empty: the newest CuPy; gpu_tests_min_cupy pins the oldest supported one
+  CUPY_PIN: ""
 
 stages:
   - test
@@ -19,7 +21,7 @@ stages:
     - module load fftw-serial/3.3.10
     - nvidia-smi
     # Keep NVRTC, CUDA libraries and headers on the same toolkit generation.
-    - python3 -m pip install --user "cupy-cuda13x[ctk]" "cuda-toolkit==13.2.*"
+    - python3 -m pip install --user "cupy-cuda13x[ctk]${CUPY_PIN}" "cuda-toolkit==13.2.*"
     - python3 -m pip install --user -e ".[test]"
     - export PATH="$HOME/.local/bin:$PATH"
     - python3 -c "import cupy; cupy.show_config()"
@@ -28,6 +30,18 @@ gpu_tests:
   extends: .gpu_job
   script:
     - python3 -m pytest -q tests
+    - python3 testing/cupyx_names.py
+
+# The oldest supported CuPy (cunumpy.MIN_CUPY_VERSION): the whole suite, and the
+# fake cupyx.scipy must list exactly its names (_fake_cupyx.NAMES).
+gpu_tests_min_cupy:
+  extends: .gpu_job
+  variables:
+    CUPY_PIN: "==14.0.0"
+  script:
+    - python3 -c "import cupy, cunumpy; assert cupy.__version__ == cunumpy.MIN_CUPY_VERSION, cupy.__version__"
+    - python3 -m pytest -q tests
+    - python3 testing/cupyx_names.py --exact
 
 gpu_sanitizers:
   extends: .gpu_job

CHANGELOG.md

@@ -8,6 +8,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 
 ### Added
+- Supported CuPy versions: 14.0 or newer (`xp.MIN_CUPY_VERSION`,
+  `xp.cupy_version_supported`); an older CuPy warns when the CuPy backend is
+  first checked, and `backend_info()` reports the minimum. The GPU CI runs the
+  whole suite on CuPy 14.0.0 too (`gpu_tests_min_cupy`).
 - MIT license (`LICENSE.txt`, referenced by `pyproject.toml`).
 - `xp.optimize.newton`: Newton's method or the secant method on many
   independent scalar equations at once, with the steps of
@@ -16,7 +20,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - The fake CuPy has `cupyx.scipy`: SciPy behind the CuPy rules (host arrays
   rejected, fake device arrays and proxy objects returned), so `xp.scipy` code
   runs its CuPy path without a GPU. Every `cupyx.scipy` subpackage has only
-  the names CuPy v14.2.0 provides, so e.g. `special.jv` fails as on a GPU.
+  the names the oldest supported CuPy (14.0.0) provides, so e.g. `special.jv`
+  or `sparse.csr_array` fails as on a GPU. `testing/cupyx_names.py` and
+  `tests/unit/test_cupyx_names.py` check these names against the installed
+  CuPy in the GPU CI.
   `cupyx.empty_pinned`/`zeros_pinned` return NumPy arrays.
 - `xp.optimize.fsolve`, `root`, `minimize` and `xp.integrate.quad`, `odeint`
   (`cupyx.scipy` has neither): SciPy on the host with SciPy's arguments, the

docs/source/guides/solvers.md

@@ -61,7 +61,9 @@ def periodic_poisson(rho, length):
   `xp.scipy.special` on both backends.
 * On the fake CuPy (tests without a GPU), `xp.scipy` runs SciPy with the CuPy
   rules: host arrays are rejected, results are fake device arrays, and each
-  subpackage has only the names CuPy has.
+  subpackage has only the names of the oldest supported CuPy
+  (`xp.MIN_CUPY_VERSION`), so code that passes there runs on every supported
+  CuPy.
 
 ## Splines and interpolation
 

docs/source/installation.md

@@ -20,8 +20,15 @@ example:
 
 ```bash
 python -m pip install cupy-cuda12x   # CUDA 12.x
+python -m pip install cupy-cuda13x   # CUDA 13.x
 ```
 
+CuNumpy supports CuPy 14.0 or newer (`xp.MIN_CUPY_VERSION`); the GPU CI tests
+14.0 and the newest release. CuPy 13 lacks parts of `cupyx.scipy` that
+CuNumpy relies on (`interpolate.UnivariateSpline`, `NdBSpline`,
+`CubicSpline`, ...): selecting the CuPy backend with an older CuPy warns.
+`xp.backend_info()` shows the installed and the minimum version.
+
 On HPC clusters, load the site's CUDA module first and check the CuPy
 installation guide for the matching package name. Then verify that CuNumpy can
 use it:

docs/source/reference/top-level.md

@@ -12,4 +12,5 @@ The NumPy/CuPy namespace (see the [API overview](../api.md)) plus backend select
 
 ```{eval-rst}
 .. autodata:: cunumpy.scipy
+.. autodata:: cunumpy.MIN_CUPY_VERSION
 ```

src/cunumpy/__init__.py

@@ -33,10 +33,12 @@
 from cunumpy._scipy_backend import scipy
 from cunumpy._staging import to_host_async
 from cunumpy.xp import (
+    MIN_CUPY_VERSION,
     as_device_array,
     assert_same_backend,
     backend_info,
     cupy_available,
+    cupy_version_supported,
     default_float_dtype,
     get_array_backend,
     get_array_module,
@@ -96,6 +98,7 @@ def require_version(minimum: str) -> None:
 
 
 __all__ = [
+    "MIN_CUPY_VERSION",
     "__version__",
     "algorithms",
     "arguments",
@@ -105,6 +108,7 @@ def require_version(minimum: str) -> None:
     "cuda",
     "cupy_available",
     "cupy_backend",
+    "cupy_version_supported",
     "default_float_dtype",
     "evaluate_on_host",
     "get_array_backend",

src/cunumpy/__init__.pyi

@@ -28,6 +28,10 @@ def to_cupy(array: Any) -> Any: ...
 def to_cunumpy(array: Any) -> Any: ...
 def to_host_async(array: Any) -> HostCopy: ...
 def cupy_available() -> bool: ...
+def cupy_version_supported(cupy_version: str) -> bool: ...
+
+MIN_CUPY_VERSION: str
+
 def backend_info() -> dict[str, Any]: ...
 def get_array_module(array: Any) -> Any: ...
 def get_backend() -> str: ...