[3.11] gh-108303: Add Lib/test/test_cppext/ sub-directory (#108325) (#108336)

gh-108303: Add Lib/test/test_cppext/ sub-directory (#108325)

* Move test_cppext to its own directory
* Rename setup_testcppext.py to setup.py
* Rename _testcppext.cpp to extension.cpp
* The source (extension.cpp) is now also copied by the test.

(cherry picked from commit 21dda09600848ac280481f7c64f8d9516dc69bb2)

1 files changed, 48 insertions, 0 deletions

diff --git a/Lib/test/test_cppext/setup.py b/Lib/test/test_cppext/setup.py
new file mode 100644
index 0000000..dac3a96
--- /dev/null
+++ b/Lib/test/test_cppext/setup.py
@@ -0,0 +1,48 @@
+# 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 sys
+
+from setuptools import setup, Extension
+
+
+MS_WINDOWS = (sys.platform == 'win32')
+
+
+SOURCE = os.path.join(os.path.dirname(__file__), 'extension.cpp')
+if not MS_WINDOWS:
+    # C++ compiler flags for GCC and clang
+    CPPFLAGS = [
+        # gh-91321: The purpose of _testcppext extension is to check that building
+        # a C++ extension using the Python C API does not emit C++ compiler
+        # warnings
+        '-Werror',
+    ]
+else:
+    # Don't pass any compiler flag to MSVC
+    CPPFLAGS = []
+
+
+def main():
+    cppflags = list(CPPFLAGS)
+    if '-std=c++03' in sys.argv:
+        sys.argv.remove('-std=c++03')
+        std = 'c++03'
+        name = '_testcpp03ext'
+    else:
+        # Python currently targets C++11
+        std = 'c++11'
+        name = '_testcpp11ext'
+
+    cppflags = [*CPPFLAGS, f'-std={std}']
+
+    cpp_ext = Extension(
+        name,
+        sources=[SOURCE],
+        language='c++',
+        extra_compile_args=cppflags)
+    setup(name='internal' + name, version='0.0', ext_modules=[cpp_ext])
+
+
+if __name__ == "__main__":
+    main()