Free-threaded Python support

.github/workflows/test.yml

@@ -33,7 +33,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python_minor: [ '9', '10', '11', '12', '13' ]
+        python_minor: [ '9', '10', '11', '12', '13', '13t' ]
         os: [ ubuntu-latest ]
         # Just a single ARM worker to be sure that it works
         include:
@@ -193,22 +193,10 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: '3.9'
-      - name: Set up Python 3.10
+      - name: Set up Python 3.13t
         uses: actions/setup-python@v5
         with:
-          python-version: '3.10'
-      - name: Set up Python 3.11
-        uses: actions/setup-python@v5
-        with:
-          python-version: '3.11'
-      - name: Set up Python 3.12
-        uses: actions/setup-python@v5
-        with:
-          python-version: '3.12'
-      - name: Set up Python 3.13
-        uses: actions/setup-python@v5
-        with:
-          python-version: '3.13'
+          python-version: '3.13t'
       - name: Get minimum supported Rust version
         run: echo "::set-output name=msrv::$(grep '^rust-version = ' Cargo.toml | grep -o '[0-9.]\+')"
         id: get_msrv
@@ -228,4 +216,5 @@ jobs:
       - name: Build
         run: |
           rustup default ${{ steps.get_msrv.outputs.msrv }}
-          maturin build --find-interpreter
+          maturin build -i python3.9
+          maturin build -i python3.13t

CHANGELOG.md

@@ -9,11 +9,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
---
+- Mark the module as no-GIL, which enables free-threading Python (can be built from source, not provided so far) https://github.com/light-curve/light-curve-python/pull/499
 
 ### Changed
 
---
+- Bump both `PyO3` and `rust-numpy` to v0.24 https://github.com/light-curve/light-curve-python/pull/499
 
 ### Deprecated
 
@@ -41,7 +41,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
-- **Experimental Feature Breaking**: change parameter limits for Rainbow https://github.com/light-curve/light-curve-python/pull/494
+- **Experimental Feature Breaking**: change parameter limits for
+  Rainbow https://github.com/light-curve/light-curve-python/pull/494
 
 ### Removed
 
@@ -50,7 +51,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
-- Rainbow multi-band scaler didn't work with list inputs https://github.com/light-curve/light-curve-python/issues/492 https://github.com/light-curve/light-curve-python/pull/493
+- Rainbow multi-band scaler didn't work with list
+  inputs https://github.com/light-curve/light-curve-python/issues/492 https://github.com/light-curve/light-curve-python/pull/493
 
 ## [0.10.0] 2025-01-07
 

light-curve/Cargo.toml

@@ -44,11 +44,11 @@ mimalloc = { version = "0.1.42", features = [
     "local_dynamic_tls",
 ], optional = true }
 ndarray = { version = "0.16.1", features = ["rayon"] }
-numpy = "0.23.0"
+numpy = "0.24.0"
 num_cpus = "1.13.0"
 num-traits = "0.2"
 once_cell = "1"
-pyo3 = { version = "0.23.5", features = [
+pyo3 = { version = "0.24.0", features = [
     "extension-module",
     "multiple-pymethods",
 ] }

light-curve/README.md

@@ -53,6 +53,9 @@ We stopped publishing all PyPy wheels (https://github.com/light-curve/light-curv
 and the PPC64le CPython glibc wheel (https://github.com/light-curve/light-curve-python/issues/479),
 please feel free to open an issue if you need any of them.
 
+[Free-threading Python](https://docs.python.org/3.13/whatsnew/3.13.html#free-threaded-cpython) is supported when built from source.
+No pre-built distributions are provided so far, please comment on these issues if you need them: [PyPI binary wheel issue](https://github.com/light-curve/light-curve-python/issues/500), [conda-forge package issue](https://github.com/conda-forge/light-curve-python-feedstock/issues/11).
+
 See [bellow](#build-from-source) for the details on how to build the package from the source code.
 
 ## Feature evaluators

light-curve/pyproject.toml

@@ -62,6 +62,19 @@ dev = [
     "black",
     "ruff",
 ]
+# cesium and iminuit don't support free-threading yet
+dev-free-threading = [
+    "pytest",
+    "markdown-pytest",
+    "pytest-benchmark",
+    "pytest-subtests>=0.10",
+    "numpy",
+    "scipy",
+    "joblib",
+    "pandas",
+    "black",
+    "ruff",
+]
 
 [tool.maturin]
 # It asks to use Cargo.lock to make the build reproducible
@@ -148,10 +161,10 @@ markers = [
 [tool.tox]
 legacy_tox_ini = """
 [tox]
-envlist = py{39,310,311,312,313}-{base,test}
+envlist = py{39,310,311,312,313,313t}-{base,test}
 isolated_build = True
 
-[testenv:py{39,310,311,312,313}-base]
+[testenv:py{39,310,311,312,313,313t}-base]
 change_dir = {envtmpdir}
 extras =
 commands =
@@ -166,6 +179,17 @@ commands =
     ruff check .
 set_env =
     CARGO_TARGET_DIR = {tox_root}/target
+
+[testenv:py313t-test]
+extras = dev-free-threading
+commands =
+    pytest README.md tests/ light_curve/ \
+        --ignore tests/test_w_bench.py \
+        --ignore=tests/light_curve_py/features/test_rainbow.py \
+        --deselect=README.md::test_rainbow_fit_example
+    ruff check .
+set_env =
+    CARGO_TARGET_DIR = {tox_root}/target
 """
 
 

light-curve/src/lib.rs

@@ -26,7 +26,7 @@ static GLOBAL_ALLOCATOR: MiMalloc = MiMalloc;
 ///
 /// dm-lg(dt) maps generator is represented by `DmDt` class, while all other classes are
 /// feature extractors
-#[pymodule]
+#[pymodule(gil_used = false)]
 fn light_curve(py: Python, m: Bound<PyModule>) -> PyResult<()> {
     m.add("__version__", env!("CARGO_PKG_VERSION"))?;
 

light-curve/tests/light_curve_ext/test_feature.py

@@ -1,6 +1,7 @@
 import copy
 import inspect
 import pickle
+from concurrent.futures import ThreadPoolExecutor
 
 import numpy as np
 import pytest
@@ -174,7 +175,24 @@ def test_many_vs_call(feature):
 
     call = np.stack([feature(*lc, sorted=True) for lc in lcs])
     many = feature.many(lcs, sorted=True, n_jobs=2)
-    assert_array_equal(many, call)
+    assert_array_equal(call, many)
+
+    # Test with Python threads to ensure we have no problems on the free-threading CPython
+    with ThreadPoolExecutor(2) as pool:
+        futures = [pool.submit(feature, *lc, sorted=True) for lc in lcs]
+        call_threads = np.stack([f.result() for f in futures])
+        del futures
+    assert_array_equal(call, call_threads)
+
+    n_lcs_per_job = 4
+    with ThreadPoolExecutor(2) as pool:
+        futures = [
+            pool.submit(feature.many, lcs[i : i + n_lcs_per_job], sorted=True, n_jobs=2)
+            for i in range(0, n_lc, n_lcs_per_job)
+        ]
+        many_threads = np.concatenate([f.result() for f in futures])
+        del futures
+    assert_array_equal(call, many_threads)
 
 
 def test_fill_value_not_enough_observations():