Replace upstream.yml with new python312.yml

.github/workflows/python312.yml

@@ -0,0 +1,140 @@
+name: Python312
+
+on:
+  workflow_dispatch:
+  pull_request:
+
+concurrency:
+  group: python312-${{ github.ref }}
+  cancel-in-progress: false
+
+env:
+  PYTEST_TIMEOUT: 300
+
+jobs:
+  standard:
+    name: "🐍 3.12 latest • ubuntu-latest • x64"
+    runs-on: ubuntu-latest
+    if: "contains(github.event.pull_request.labels.*.name, 'python dev')"
+
+    steps:
+    - name: Show env
+      run: env
+
+    - uses: actions/checkout@v3
+
+    - name: Setup Python 3.12
+      uses: actions/setup-python@v4
+      with:
+        python-version: "3.12-dev"
+
+    - name: Setup Boost
+      run: sudo apt-get install libboost-dev
+
+    - name: Update CMake
+      uses: jwlawson/actions-setup-cmake@v1.13
+
+    - name: Run pip installs
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install --prefer-binary -r tests/requirements.txt
+    #   python -m pip install --prefer-binary numpy  # SLOW
+    #   python -m pip install --prefer-binary scipy  # FAILED ~Nov 2022
+
+    - name: Show platform info
+      run: python -m platform
+
+    - name: Show CMake version
+      run: cmake --version
+
+    # FIRST BUILD
+    - name: Configure C++11
+      run: >
+        cmake -S . -B build11
+        -DCMAKE_VERBOSE_MAKEFILE=ON
+        -DPYBIND11_WERROR=ON
+        -DDOWNLOAD_CATCH=ON
+        -DDOWNLOAD_EIGEN=ON
+        -DCMAKE_CXX_STANDARD=11
+        -DCMAKE_BUILD_TYPE=Debug
+
+    - name: Build C++11
+      run: cmake --build build11 -j 2
+
+    - name: Python tests C++11
+      run: cmake --build build11 --target pytest -j 2
+
+    # python-3.12.0-alpha.1-linux-22.04-x64.tar.gz  PASSED
+    # python-3.12.0-alpha.2-linux-22.04-x64.tar.gz  FAILED
+    # python-3.12.0-alpha.3-linux-22.04-x64.tar.gz  FAILED
+    #     free(): invalid pointer
+    #     Custom PyConfig
+    #     /home/runner/work/pybind11/pybind11/tests/test_embed/test_interpreter.cpp:175
+    #     /home/runner/work/pybind11/pybind11/tests/test_embed/test_interpreter.cpp:179: FAILED:
+    # gdb traceback points here:
+    #     https://github.com/python/cpython/blame/54289f85b2af1ecf046089ddf535dda1bdf6af24/Python/import.c#L524
+    # - name: C++ tests C++11
+    #   run: cmake --build build11 --target cpptest -j 2
+
+    - name: Interface test C++11
+      run: cmake --build build11 --target test_cmake_build
+
+    - name: Clean directory
+      run: git clean -fdx
+
+    # SECOND BUILD
+    - name: Configure C++17
+      run: >
+        cmake -S . -B build17
+        -DCMAKE_VERBOSE_MAKEFILE=ON
+        -DPYBIND11_WERROR=ON
+        -DDOWNLOAD_CATCH=ON
+        -DDOWNLOAD_EIGEN=ON
+        -DCMAKE_CXX_STANDARD=17
+        -DCMAKE_BUILD_TYPE=Debug
+
+    - name: Build C++17
+      run: cmake --build build17 -j 2
+
+    - name: Python tests C++17
+      run: cmake --build build17 --target pytest
+
+    # - name: C++ tests C++17
+    #   run: cmake --build build17 --target cpptest
+
+    - name: Interface test C++17
+      run: cmake --build build17 --target test_cmake_build
+
+    - name: Clean directory
+      run: git clean -fdx
+
+    # THIRD BUILD
+    - name: Configure C++17 max DPYBIND11_INTERNALS_VERSION
+      run: >
+        cmake -S . -B build17max
+        -DCMAKE_VERBOSE_MAKEFILE=ON
+        -DPYBIND11_WERROR=ON
+        -DDOWNLOAD_CATCH=ON
+        -DDOWNLOAD_EIGEN=ON
+        -DCMAKE_CXX_STANDARD=17
+        -DCMAKE_BUILD_TYPE=Debug
+        -DPYBIND11_INTERNALS_VERSION=10000000
+
+    - name: Build C++17 max DPYBIND11_INTERNALS_VERSION
+      run: cmake --build build17max -j 2
+
+    - name: Python tests C++17 max DPYBIND11_INTERNALS_VERSION
+      run: cmake --build build17max --target pytest
+
+    # - name: C++ tests C++17 max DPYBIND11_INTERNALS_VERSION
+    #   run: cmake --build build17max --target cpptest
+
+    - name: Interface test C++17 max DPYBIND11_INTERNALS_VERSION
+      run: cmake --build build17max --target test_cmake_build
+
+    # Ensure the setup_helpers module can build packages using setuptools
+    - name: Setuptools helpers test
+      run: pytest tests/extra_setuptools
+
+    - name: Clean directory
+      run: git clean -fdx