%bcond test_example 1

Name:           python-cmake-build-extension

Version:        0.5.1

Release:        %autorelease

Summary:        Setuptools extension to build and package CMake projects

# The entire source is MIT, except example/bindings_swig/numpy.i, which is

# BSD-3-Clause, and test_example/bindings_swig/numpy.i, which is also

# BSD-3-Clause but does not contribute to any of the binary RPMs.

License:        MIT AND BSD-3-Clause

URL:            https://github.com/diegoferigo/cmake-build-extension

Source:         %{pypi_source cmake-build-extension}

BuildArch:      noarch

BuildRequires:  python3-devel

BuildRequires:  cmake

BuildRequires:  ninja-build

%if %{with test_example}

BuildRequires:  gcc

BuildRequires:  gcc-c++

BuildRequires:  swig

# Even though pybind11 and eigen3 are  header-only, we don’t need to BR:

# pybind11-static nor eigen3-static, because nothing we install is built with

# them; they are only used for test-building the example.

BuildRequires:  cmake(pybind11)

BuildRequires:  cmake(Eigen3)

BuildRequires:  python3dist(pytest)

%endif

%global common_description %{expand:

This project aims to simplify the integration of C++ projects based on CMake

with Python packaging tools. CMake provides out-of-the-box support to either

SWIG and pybind11, that are two among the most used projects to create Python

bindings from C++ sources.

If you have any experience with these hybrid projects, you know the challenges

to make packaging right! This project takes inspiration from pre-existing

examples (pybind/cmake_example, among many others) and provides a simple,

flexible, and reusable setuptools extension with the following features:

  • Bridge between CMake projects and Python packaging.

  • Configure and build the CMake project from setup.py.

  • Install the CMake project in the resulting Python package.

  • Allow passing custom CMake options.

  • Allow creating a top-level __init__.py.

  • Expose C++ executables to the Python environment.

  • Provide a context manager to import reliably CPython modules on all major

    OSs.

  • Disable the C++ extension in editable installations (requiring to manually

    call CMake to install the C++ project).}

%description %{common_description}

%package -n python3-cmake-build-extension

Summary:        %{summary}

# Since this subpackage does not contain the example project, it has no

# BSD-3-Clause licensed sources.

License:        MIT

Requires:       cmake

Requires:       ninja-build

%description -n python3-cmake-build-extension %{common_description}

%package -n python3-cmake-build-extension-doc

Summary:        Documentation and examples for cmake-build-extension

Requires:       python3-cmake-build-extension = %{version}-%{release}

%description -n python3-cmake-build-extension-doc %{common_description}

%prep

%autosetup -n cmake-build-extension-%{version} -p1

# We use the system cmake and ninja-build packages in lieu of the PyPI “cmake”

# and “ninja” distributions, respectively.

sed -r -i '/^[[:blank:]]*\b(cmake|ninja)\b[[:blank:]]*$/d' setup.cfg

%if %{with test_example}

# Keep the original example/ “clean” so we can install it as documentation;

# make a copy to test-build.

cp -rp example test_example

%endif

%generate_buildrequires

%pyproject_buildrequires

%if %{with test_example}

(

  cd test_example >/dev/null

  # For an unknown reason, “-x test” does not generate the appropriate BR’s

  # here. Furthermore, python3dist(pytest-icdiff) is not packaged, so we would

  # have to patch it out anyway. We just use manual BR’s for the example’s

  # tests instead.

  %pyproject_buildrequires

) | grep -Ev 'cmake-build-extension'

%endif

%build

%pyproject_wheel

%install

%pyproject_install

%pyproject_save_files -l cmake_build_extension

%check

# We choose to do an import “smoke test” even when we are test-building the

# example.

%pyproject_check_import

%if %{with test_example}

# Build the example project and run its tests (but do not install any compiled

# extensions as part of our RPM!)

pushd test_example >/dev/null

export PYTHONPATH='%{buildroot}%{python3_sitelib}'

%pyproject_wheel

BLIB="${PWD}/build/lib.%{python3_platform}-cpython-%{python3_version_nodots}"

export PYTHONPATH="${PYTHONPATH}:${BLIB}"

export PATH="${PATH}:${BLIB}/mymath_pybind11/bin:${BLIB}/mymath_swig/bin"

%pytest

popd >/dev/null

%endif

%files -n python3-cmake-build-extension -f %{pyproject_files}

# pyproject_files handles LICENSE; verify with “rpm -qL -p …”

%files -n python3-cmake-build-extension-doc

%doc README.md

%doc example/

%changelog

%autochangelog