Fix for free-threaded Python tests

Author: benoit74

README.md

@@ -29,6 +29,8 @@ Our [PyPI wheels](https://pypi.org/project/libzim/) bundle a [recent release](ht
 
 Wheels are available for CPython only (but can be built for Pypy).
 
+Free-threaded CPython is not supported. If you use a free-threaded CPython, GIL must be turned on (using the environment variable PYTHON_GIL or the command-line option -X gil). If you don't turn it on yourself, GIL will be forced-on and you will get a warning. Only few methods support the GIL to be disabled.
+
 Users on other platforms can install the source distribution (see [Building](#Building) below). 
 
 

pyproject.toml

@@ -123,6 +123,11 @@ skip = "pp* *win32*"
 test-requires = ["pytest"]
 test-command = "py.test {project}/tests/"
 
+# Override test command for free-threaded builds to force GIL on
+[[tool.cibuildwheel.overrides]]
+select = "cp313t-* cp314t-*"
+test-command = "python -X gil=1 -m pytest {project}/tests/"
+
 manylinux-x86_64-image = "manylinux_2_28"
 manylinux-aarch64-image = "manylinux_2_28"
 manylinux-pypy_x86_64-image = "manylinux_2_28"

tests/test_libzim_creator.py

@@ -162,8 +162,20 @@ def get_creator_output(fpath, verbose):
     ).replace(
         "{verbose}", str(verbose)
     )
+
+    # Build command with appropriate GIL settings for free-threaded Python
+    cmd = [sys.executable]
+
+    # Check if we're running in free-threaded mode (Python 3.13+)
+    if sys.version_info >= (3, 13) and hasattr(sys, "_is_gil_enabled"):
+        # If GIL is enabled, explicitly pass -X gil=1 to subprocess
+        if sys._is_gil_enabled():
+            cmd.extend(["-X", "gil=1"])
+
+    cmd.extend(["-c", code])
+
     ps = subprocess.run(
-        [sys.executable, "-c", code],
+        cmd,
         stdout=subprocess.PIPE,
         stderr=subprocess.STDOUT,
         text=True,