# gh-91321: Build a basic C++ test extension to check that the Python C API is # compatible with C++ and does not emit C++ compiler warnings. import os.path import shlex import shutil import subprocess import unittest from test import support SOURCE = os.path.join(os.path.dirname(__file__), 'extension.cpp') SETUP = os.path.join(os.path.dirname(__file__), 'setup.py') # With MSVC on a debug build, the linker fails with: cannot open file # 'python311.lib', it should look 'python311_d.lib'. @unittest.skipIf(support.MS_WINDOWS and support.Py_DEBUG, 'test fails on Windows debug build') # Building and running an extension in clang sanitizing mode is not # straightforward @support.skip_if_sanitizer('test does not work with analyzing builds', address=True, memory=True, ub=True, thread=True) # the test uses venv+pip: skip if it's not available @support.requires_venv_with_pip() @support.requires_subprocess() @support.requires_resource('cpu') class TestCPPExt(unittest.TestCase): def test_build(self): self.check_build('_testcppext') def test_build_cpp03(self): self.check_build('_testcpp03ext', std='c++03') @unittest.skipIf(support.MS_WINDOWS, "MSVC doesn't support /std:c++11") def test_build_cpp11(self): self.check_build('_testcpp11ext', std='c++11') # Only test C++14 on MSVC. # On s390x RHEL7, GCC 4.8.5 doesn't support C++14. @unittest.skipIf(not support.MS_WINDOWS, "need Windows") def test_build_cpp14(self): self.check_build('_testcpp14ext', std='c++14') def check_build(self, extension_name, std=None): venv_dir = 'env' with support.setup_venv_with_pip_setuptools_wheel(venv_dir) as python_exe: self._check_build(extension_name, python_exe, std=std) def _check_build(self, extension_name, python_exe, std): pkg_dir = 'pkg' os.mkdir(pkg_dir) shutil.copy(SETUP, os.path.join(pkg_dir, os.path.basename(SETUP))) shutil.copy(SOURCE, os.path.join(pkg_dir, os.path.basename(SOURCE))) def run_cmd(operation, cmd): env = os.environ.copy() if std: env['CPYTHON_TEST_CPP_STD'] = std env['CPYTHON_TEST_EXT_NAME'] = extension_name if support.verbose: print('Run:', ' '.join(map(shlex.quote, cmd))) subprocess.run(cmd, check=True, env=env) else: proc = subprocess.run(cmd, env=env, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, text=True) if proc.returncode: print('Run:', ' '.join(map(shlex.quote, cmd))) print(proc.stdout, end='') self.fail( f"{operation} failed with exit code {proc.returncode}") # Build and install the C++ extension cmd = [python_exe, '-X', 'dev', '-m', 'pip', 'install', '--no-build-isolation', os.path.abspath(pkg_dir)] if support.verbose: cmd.append('-v') run_cmd('Install', cmd) # Do a reference run. Until we test that running python # doesn't leak references (gh-94755), run it so one can manually check # -X showrefcount results against this baseline. cmd = [python_exe, '-X', 'dev', '-X', 'showrefcount', '-c', 'pass'] run_cmd('Reference run', cmd) # Import the C++ extension cmd = [python_exe, '-X', 'dev', '-X', 'showrefcount', '-c', f"import {extension_name}"] run_cmd('Import', cmd) if __name__ == "__main__": unittest.main()