Improve test coverage.

Update scripts to use actions/setup-python to install different Python
versions.  Add run-faber.sh and get-py-env.py scripts.  Add
test-ubuntu-py-ver.yml CI script to test with different Python versions.

.github/get-py-env.py

@@ -0,0 +1,65 @@
+#!/usr/bin/env python3
+#
+# Determine info about the Python install and write shell code to stdout, to
+# set env variables.  This will set the variables PY_LDFLAGS, PY_CFLAGS and
+# PY_INC_PATH.
+#
+# The python3-config tool is used as the source of this info. In theory we
+# could use sysconfig as well but the setup-python action from github appears
+# to patch python3-config but not patch the sysconfig info.
+#
+# Usage:
+#   eval $(python3 get-py-env.py)
+
+import os
+import re
+import subprocess
+
+
+def get_output(cmd):
+    rv = subprocess.run(
+        cmd,
+        capture_output=True,  # Capture stdout and stderr
+        text=True,  # Decode output as text (UTF-8)
+        check=True,  # Raise an error if the command fails
+    )
+    return rv.stdout
+
+
+def extract_flags(cmd, prefix):
+    flags = []
+    for part in get_output(cmd).split():
+        part = part.strip()
+        if part.startswith(prefix):
+            flags.append(part)
+    return ' '.join(flags)
+
+
+def find_python_h():
+    """Find the include path that has Python.h contained inside.
+    We could use INCLUDEPY from sysconfig but github patches
+    python3-config but not the sysconfig info (after moving the
+    install).
+    """
+    c_flags = extract_flags(['python3-config', '--cflags'], '-I')
+    for part in c_flags.split():
+        m = re.search(r'-I(\S+)', part)
+        if not m:
+            continue
+        inc_path = m.group(1)
+        if os.path.exists(os.path.join(inc_path, 'Python.h')):
+            return inc_path
+    raise SystemExit('cannot find Python.h')
+
+
+def main():
+    ld_flags = extract_flags(['python3-config', '--ldflags'], '-L')
+    c_flags = extract_flags(['python3-config', '--cflags'], '-I')
+    include_path = find_python_h()
+    print(f'PY_LDFLAGS="{ld_flags}"')
+    print(f'PY_CFLAGS="{c_flags}"')
+    print(f'PY_INC_PATH="{include_path}"')
+
+
+if __name__ == '__main__':
+    main()

.github/run-faber.sh

@@ -0,0 +1,46 @@
+#!/bin/sh
+
+set -eu
+
+echo "cxx version: $CXX $($CXX --version)"
+echo "cxx std: $CXX_STD"
+echo "python3 path: $(which python3)"
+echo "python3 version: $(python3 --version)"
+
+if ! which faber > /dev/null; then
+    echo "Installing faber..."
+    python3 -m pip install --upgrade pip
+    python3 -m pip install -U faber
+fi
+echo "faber version: $(faber -v)"
+
+# find and set PY_LDFLAGS and PY_INC_PATH
+eval $(python3 .github/get-py-env.py)
+
+echo "PY_INC_PATH=$PY_INC_PATH"
+echo "PY_LDFLAGS=$PY_LDFLAGS"
+
+case $(python3-config --abiflags) in
+    *t*)
+        # When running with free-threaded, we always want to disable the GIL
+        # even for extensions without the mod_gil_not_used() flag
+        export PYTHON_GIL=0
+        ;;
+esac
+
+# this could be set by LD_LIBRARY_PATH but faber overrides it
+prefix=$(python3-config --prefix)
+echo "${prefix}/lib" > /etc/ld.so.conf.d/boost-ci.conf && ldconfig
+
+sed -e "s/\$PYTHON/python3/g" .ci/faber > $HOME/.faber
+
+faber \
+  --with-boost-include=${BOOST_PY_DEPS} \
+  --builddir=build \
+  cxx.name="${CXX}" \
+  cxxflags="-std=${CXX_STD}" \
+  cppflags="-std=${CXX_STD}" \
+  include="${PY_INC_PATH}" \
+  ldflags="${PY_LDFLAGS}" \
+  -j`nproc` \
+  "$@"

.github/workflows/test-ubuntu.yml

@@ -1,6 +1,10 @@
+# Test on Ubuntu with various compiler and language standard versions.
 name: Test Ubuntu
 
-on:  [push, pull_request]
+on:
+  push:
+  pull_request:
+  workflow_dispatch:
 
 jobs:
   build:
@@ -9,35 +13,59 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python: [python, python3]
+        python-version: ['3.14']
         cxx: [g++, clang++]
         std: [c++11, c++14, c++17]
         include:
-          # Add the appropriate docker image for each compiler.
+          - python-version: '2.7'
-          # The images from teeks99/boost-python-test already have boost::python
+            cxx: g++
-          # pre-reqs installed, see:
+            std: c++11
-          # https://github.com/teeks99/boost-python-test-docker
+          - python-version: '3.10'
-          - cxx: clang++
+            cxx: g++
-            docker-img: teeks99/boost-python-test:clang-21_1.89.0
+            std: c++17
-          - cxx: g++
+          - python-version: '3.11'
-            docker-img: teeks99/boost-python-test:gcc-15_1.89.0
+            cxx: g++
+            std: c++17
+          - python-version: '3.12'
+            cxx: g++
+            std: c++17
+          - python-version: '3.13'
+            cxx: g++
+            std: c++17
+          # Also test with free-threaded build of Python
+          - python-version: '3.14t'
+            cxx: clang++
+            std: c++17
 
     container:
-      image: ${{ matrix.docker-img }}
+      # Add the appropriate docker image for the compiler.
+      # The images from teeks99/boost-python-test already have boost::python
+      # pre-reqs installed, see:
+      # https://github.com/teeks99/boost-python-test-docker
+      image: ${{ matrix.cxx == 'g++' &&
+        'teeks99/boost-python-test:gcc-15_1.89.0' ||
+        'teeks99/boost-python-test:clang-21_1.89.0' }}
 
     steps:
     - uses: actions/checkout@v5
-
+    - name: setup python
+      if: "${{ matrix.python-version  != '2.7' }}"
+      uses: actions/setup-python@v5
+      with:
+        python-version: ${{ matrix.python-version }}
     - name: setup prerequisites
       run: |
         # Warning: this is not necessarily the same Python version as the one configured above !
         python3 -m pip install -U faber --break-system-packages
-    - name: build
+        echo "CXX=${{ matrix.cxx }}" >> "$GITHUB_ENV"
+        echo "CXX_STD=${{ matrix.std }}" >> "$GITHUB_ENV"
+    - name: build-py2
+      if: "${{ matrix.python-version  == '2.7' }}"
       run: |
-        ${{ matrix.python }} --version
+        python --version
         ${{ matrix.cxx }} --version
         faber -v
-        sed -e "s/\$PYTHON/${{ matrix.python }}/g" .ci/faber > ~/.faber
+        sed -e "s/\$PYTHON/python/g" .ci/faber > ~/.faber
         faber \
           --with-boost-include=${BOOST_PY_DEPS} \
           --builddir=build \
@@ -45,7 +73,12 @@ jobs:
           cxxflags=-std=${{ matrix.std }} \
           cppflags=-std=${{ matrix.std }} \
           -j`nproc`
-    - name: test
+    - name: build-py3
+      if: "${{ matrix.python-version  != '2.7' }}"
+      run: |
+        .github/run-faber.sh
+    - name: test-py2
+      if: "${{ matrix.python-version  == '2.7' }}"
       run: |
         faber \
           --with-boost-include=${BOOST_PY_DEPS} \
@@ -55,3 +88,7 @@ jobs:
           cppflags=-std=${{ matrix.std }} \
           -j`nproc` \
           test.report
+    - name: test-py3
+      if: "${{ matrix.python-version  != '2.7' }}"
+      run: |
+        .github/run-faber.sh test.report

include/boost/python/module_init.hpp

@@ -11,11 +11,41 @@
 
 # ifndef BOOST_PYTHON_MODULE_INIT
 
-namespace boost { namespace python { namespace detail {
+namespace boost { namespace python {
+
+#ifdef HAS_CXX11
+// Use to activate the Py_MOD_GIL_NOT_USED flag.
+class mod_gil_not_used {
+public:
+    explicit mod_gil_not_used(bool flag = true) : flag_(flag) {}
+    bool flag() const { return flag_; }
+
+private:
+    bool flag_;
+};
+
+namespace detail {
+
+inline bool gil_not_used_option() { return false; }
+template <typename F, typename... O>
+bool gil_not_used_option(F &&, O &&...o);
+template <typename... O>
+inline bool gil_not_used_option(mod_gil_not_used f, O &&...o) {
+    return f.flag() || gil_not_used_option(o...);
+}
+template <typename F, typename... O>
+inline bool gil_not_used_option(F &&, O &&...o) {
+    return gil_not_used_option(o...);
+}
+
+}
+#endif // HAS_CXX11
+
+namespace detail {
 
 #  if PY_VERSION_HEX >= 0x03000000
 
-BOOST_PYTHON_DECL PyObject* init_module(PyModuleDef&, void(*)());
+BOOST_PYTHON_DECL PyObject* init_module(PyModuleDef&, void(*)(), bool gil_not_used = false);
 
 #else
 
@@ -27,7 +57,37 @@ BOOST_PYTHON_DECL PyObject* init_module(char const* name, void(*)());
 
 #  if PY_VERSION_HEX >= 0x03000000
 
-#   define _BOOST_PYTHON_MODULE_INIT(name) \
+#   ifdef HAS_CXX11
+#    define _BOOST_PYTHON_MODULE_INIT(name, ...) \
+  PyObject* BOOST_PP_CAT(PyInit_, name)()  \
+  { \
+    static PyModuleDef_Base initial_m_base = { \
+        PyObject_HEAD_INIT(NULL) \
+        0, /* m_init */ \
+        0, /* m_index */ \
+        0 /* m_copy */ };  \
+    static PyMethodDef initial_methods[] = { { 0, 0, 0, 0 } }; \
+ \
+    static struct PyModuleDef moduledef = { \
+        initial_m_base, \
+        BOOST_PP_STRINGIZE(name), \
+        0, /* m_doc */ \
+        -1, /* m_size */ \
+        initial_methods, \
+        0,  /* m_reload */ \
+        0, /* m_traverse */ \
+        0, /* m_clear */ \
+        0,  /* m_free */ \
+    }; \
+ \
+    return boost::python::detail::init_module( \
+        moduledef, BOOST_PP_CAT(init_module_, name), \
+        boost::python::detail::gil_not_used_option(__VA_ARGS__) ); \
+  } \
+  void BOOST_PP_CAT(init_module_, name)()
+
+#   else // !HAS_CXX11
+#    define _BOOST_PYTHON_MODULE_INIT(name) \
   PyObject* BOOST_PP_CAT(PyInit_, name)()  \
   { \
     static PyModuleDef_Base initial_m_base = { \
@@ -53,6 +113,7 @@ BOOST_PYTHON_DECL PyObject* init_module(char const* name, void(*)());
         moduledef, BOOST_PP_CAT(init_module_, name) ); \
   } \
   void BOOST_PP_CAT(init_module_, name)()
+#   endif // HAS_CXX11
 
 #  else
 
@@ -66,9 +127,15 @@ BOOST_PYTHON_DECL PyObject* init_module(char const* name, void(*)());
 
 #  endif
 
-#  define BOOST_PYTHON_MODULE_INIT(name)                       \
+#  if defined(HAS_CXX11) && (PY_VERSION_HEX >= 0x03000000)
+#   define BOOST_PYTHON_MODULE_INIT(name, ...)                  \
+  void BOOST_PP_CAT(init_module_,name)();                      \
+extern "C" BOOST_SYMBOL_EXPORT _BOOST_PYTHON_MODULE_INIT(name, __VA_ARGS__)
+#  else
+#   define BOOST_PYTHON_MODULE_INIT(name)                       \
   void BOOST_PP_CAT(init_module_,name)();                      \
 extern "C" BOOST_SYMBOL_EXPORT _BOOST_PYTHON_MODULE_INIT(name)
+#  endif // HAS_CXX11 && Python 3
 
 # endif
 

src/module.cpp

@@ -38,11 +38,12 @@ BOOST_PYTHON_DECL void scope_setattr_doc(char const* name, object const& x, char
 
 #if PY_VERSION_HEX >= 0x03000000
 
-BOOST_PYTHON_DECL PyObject* init_module(PyModuleDef& moduledef, void(*init_function)())
+BOOST_PYTHON_DECL PyObject* init_module(PyModuleDef& moduledef,
+    void(*init_function)(), bool gil_not_used)
 {
     PyObject *mod = PyModule_Create(&moduledef);
 #ifdef Py_GIL_DISABLED
-    if (mod != NULL) {
+    if (mod != NULL && gil_not_used) {
         PyUnstable_Module_SetGIL(mod, Py_MOD_GIL_NOT_USED);
     }
 #endif

test/fabscript

@@ -68,6 +68,7 @@ for t in [('injected',),
           ('raw_ctor',),
           ('exception_translator',),
           ('module_init_exception',),
+          ('module_nogil',),
           ('test_enum', ['enum_ext']),
           ('test_cltree', ['cltree']),
           ('newtest', ['m1', 'm2']),

test/module_nogil.cpp

@@ -0,0 +1,25 @@
+// Test for BOOST_PYTHON_MODULE with optional mod_gil_not_used argument
+
+#include <boost/python/module.hpp>
+#include <boost/python/def.hpp>
+
+// Simple function to export
+int get_value() {
+    return 1234;
+}
+
+#if defined(HAS_CXX11) && (PY_VERSION_HEX >= 0x03000000)
+// C++11 build with Python 3: test with mod_gil_not_used option
+BOOST_PYTHON_MODULE(module_nogil_ext, boost::python::mod_gil_not_used())
+{
+    using namespace boost::python;
+    def("get_value", get_value);
+}
+#else
+// C++98 build or Python 2: test without optional arguments
+BOOST_PYTHON_MODULE(module_nogil_ext)
+{
+    using namespace boost::python;
+    def("get_value", get_value);
+}
+#endif

test/module_nogil.py

@@ -0,0 +1,29 @@
+"""
+>>> from module_nogil_ext import *
+>>> get_value()
+1234
+>>> import sys, sysconfig
+>>> Py_GIL_DISABLED = bool(sysconfig.get_config_var('Py_GIL_DISABLED'))
+>>> if Py_GIL_DISABLED and sys._is_gil_enabled():
+...    print('GIL is enabled and should not be')
+... else:
+...    print('okay')
+okay
+"""
+
+from __future__ import print_function
+
+def run(args = None):
+    import sys
+    import doctest
+
+    if args is not None:
+        sys.argv = args
+    return doctest.testmod(sys.modules.get(__name__))
+
+if __name__ == '__main__':
+    print("running...")
+    import sys
+    status = run()[0]
+    if (status == 0): print("Done.")
+    sys.exit(status)