python 3.13 (which requires cython 3) remove 3.8

[cmacdonald]

recent comments on #739 suggested problems building on Python 3.13; Through experimentation on GHAs, I found that Python 3.13 requires Cython 3.

The enclosed PR forces use of Cython 3 for Python 3.13.

Thanks to @gituser789 and @white-gecko for spotting it was about Python versions.

[white-gecko]

Unfortunately trying to install this branch with poetry fails, even without a lot of output :-\

$ poetry add git+https://github.com/cmacdonald/pyjnius.git#py3.13

Updating dependencies
Resolving dependencies... (0.1s)

Package operations: 1 install, 0 updates, 0 removals

  - Installing pyjnius (1.6.1 dbce629): Failed

In a python 3.13.2 environment.

[white-gecko]

Here is the output:

$ poetry run pip install --verbose git+https://github.com/cmacdonald/pyjnius.git@py3.13
Using pip 25.0.1 from /myhome/.cache/pypoetry/virtualenvs/pyjn--CgpPmpQ-py3.13/lib/python3.13/site-packages/pip (python 3.13)
Collecting git+https://github.com/cmacdonald/pyjnius.git@py3.13
  Cloning https://github.com/cmacdonald/pyjnius.git (to revision py3.13) to /tmp/pip-req-build-k7mu6v1r
  Running command git version
  git version 2.49.0
  Running command git clone --filter=blob:none https://github.com/cmacdonald/pyjnius.git /tmp/pip-req-build-k7mu6v1r
  Cloning into '/tmp/pip-req-build-k7mu6v1r'...
  Running command git show-ref py3.13
  dbce6298e81d248998dae715b16f171290cdcd86 refs/remotes/origin/py3.13
  Running command git symbolic-ref -q HEAD
  refs/heads/master
  Running command git checkout -b py3.13 --track origin/py3.13
  Switched to a new branch 'py3.13'
  branch 'py3.13' set up to track 'origin/py3.13'.
  Resolved https://github.com/cmacdonald/pyjnius.git to commit dbce6298e81d248998dae715b16f171290cdcd86
  Running command git rev-parse HEAD
  dbce6298e81d248998dae715b16f171290cdcd86
  Running command pip subprocess to install build dependencies
  Using pip 25.0.1 from /myhome/.cache/pypoetry/virtualenvs/pyjn--CgpPmpQ-py3.13/lib/python3.13/site-packages/pip (python 3.13)
  Ignoring Cython: markers 'python_version < "3.13"' don't match your environment
  Collecting setuptools>=58.0.0
    Obtaining dependency information for setuptools>=58.0.0 from https://files.pythonhosted.org/packages/54/21/f43f0a1fa8b06b32812e0975981f4677d28e0f3271601dc88ac5a5b83220/setuptools-78.1.0-py3-none-any.whl.metadata
    Using cached setuptools-78.1.0-py3-none-any.whl.metadata (6.6 kB)
  Collecting wheel
    Obtaining dependency information for wheel from https://files.pythonhosted.org/packages/0b/2c/87f3254fd8ffd29e4c02732eee68a83a1d3c346ae39bc6822dcbcb697f2b/wheel-0.45.1-py3-none-any.whl.metadata
    Using cached wheel-0.45.1-py3-none-any.whl.metadata (2.3 kB)
  Collecting Cython>3
    Obtaining dependency information for Cython>3 from https://files.pythonhosted.org/packages/a8/30/7f48207ea13dab46604db0dd388e807d53513ba6ad1c34462892072f8f8c/Cython-3.0.12-cp313-cp313-manylinux_2_17_x86_64.manylinux2014_x86_64.whl.metadata
    Using cached Cython-3.0.12-cp313-cp313-manylinux_2_17_x86_64.manylinux2014_x86_64.whl.metadata (3.5 kB)
  Using cached setuptools-78.1.0-py3-none-any.whl (1.3 MB)
  Using cached wheel-0.45.1-py3-none-any.whl (72 kB)
  Using cached Cython-3.0.12-cp313-cp313-manylinux_2_17_x86_64.manylinux2014_x86_64.whl (3.5 MB)
  Installing collected packages: wheel, setuptools, Cython
    Creating /tmp/pip-build-env-t5jgczlh/overlay/bin
    changing mode of /tmp/pip-build-env-t5jgczlh/overlay/bin/wheel to 755
    changing mode of /tmp/pip-build-env-t5jgczlh/overlay/bin/cygdb to 755
    changing mode of /tmp/pip-build-env-t5jgczlh/overlay/bin/cython to 755
    changing mode of /tmp/pip-build-env-t5jgczlh/overlay/bin/cythonize to 755
  Successfully installed Cython-3.0.12 setuptools-78.1.0 wheel-0.45.1
  Installing build dependencies ... done
  Running command Getting requirements to build wheel
  warning: [options] bootstrap class path not set in conjunction with -source 8
  warning: [options] source value 8 is obsolete and will be removed in a future release
  warning: [options] target value 8 is obsolete and will be removed in a future release
  warning: [options] To suppress warnings about obsolete options, use -Xlint:-options.
  4 warnings
  /tmp/pip-build-env-t5jgczlh/overlay/lib/python3.13/site-packages/setuptools/dist.py:759: SetuptoolsDeprecationWarning: License classifiers are deprecated.
  !!

          ********************************************************************************
          Please consider removing the following classifiers in favor of a SPDX license expression:

          License :: OSI Approved :: MIT License

          See https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#license for details.
          ********************************************************************************

  !!
    self._finalize_license_expression()
  running egg_info
  creating pyjnius.egg-info
  writing pyjnius.egg-info/PKG-INFO
  writing dependency_links to pyjnius.egg-info/dependency_links.txt
  writing requirements to pyjnius.egg-info/requires.txt
  writing top-level names to pyjnius.egg-info/top_level.txt
  writing manifest file 'pyjnius.egg-info/SOURCES.txt'
  reading manifest file 'pyjnius.egg-info/SOURCES.txt'
  reading manifest template 'MANIFEST.in'
  adding license file 'LICENSE'
  writing manifest file 'pyjnius.egg-info/SOURCES.txt'
  Getting requirements to build wheel ... done
  Running command Preparing metadata (pyproject.toml)
  warning: [options] bootstrap class path not set in conjunction with -source 8
  warning: [options] source value 8 is obsolete and will be removed in a future release
  warning: [options] target value 8 is obsolete and will be removed in a future release
  warning: [options] To suppress warnings about obsolete options, use -Xlint:-options.
  4 warnings
  /tmp/pip-build-env-t5jgczlh/overlay/lib/python3.13/site-packages/setuptools/dist.py:759: SetuptoolsDeprecationWarning: License classifiers are deprecated.
  !!

          ********************************************************************************
          Please consider removing the following classifiers in favor of a SPDX license expression:

          License :: OSI Approved :: MIT License

          See https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#license for details.
          ********************************************************************************

  !!
    self._finalize_license_expression()
  running dist_info
  creating /tmp/pip-modern-metadata-tefr9o3_/pyjnius.egg-info
  writing /tmp/pip-modern-metadata-tefr9o3_/pyjnius.egg-info/PKG-INFO
  writing dependency_links to /tmp/pip-modern-metadata-tefr9o3_/pyjnius.egg-info/dependency_links.txt
  writing requirements to /tmp/pip-modern-metadata-tefr9o3_/pyjnius.egg-info/requires.txt
  writing top-level names to /tmp/pip-modern-metadata-tefr9o3_/pyjnius.egg-info/top_level.txt
  writing manifest file '/tmp/pip-modern-metadata-tefr9o3_/pyjnius.egg-info/SOURCES.txt'
  reading manifest file '/tmp/pip-modern-metadata-tefr9o3_/pyjnius.egg-info/SOURCES.txt'
  reading manifest template 'MANIFEST.in'
  adding license file 'LICENSE'
  writing manifest file '/tmp/pip-modern-metadata-tefr9o3_/pyjnius.egg-info/SOURCES.txt'
  creating '/tmp/pip-modern-metadata-tefr9o3_/pyjnius-1.6.1.dist-info'
  Preparing metadata (pyproject.toml) ... done
Building wheels for collected packages: pyjnius
  Running command git rev-parse HEAD
  dbce6298e81d248998dae715b16f171290cdcd86
  Running command Building wheel for pyjnius (pyproject.toml)
  warning: [options] bootstrap class path not set in conjunction with -source 8
  warning: [options] source value 8 is obsolete and will be removed in a future release
  warning: [options] target value 8 is obsolete and will be removed in a future release
  warning: [options] To suppress warnings about obsolete options, use -Xlint:-options.
  4 warnings
  /tmp/pip-build-env-t5jgczlh/overlay/lib/python3.13/site-packages/setuptools/dist.py:759: SetuptoolsDeprecationWarning: License classifiers are deprecated.
  !!

          ********************************************************************************
          Please consider removing the following classifiers in favor of a SPDX license expression:

          License :: OSI Approved :: MIT License

          See https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#license for details.
          ********************************************************************************

  !!
    self._finalize_license_expression()
  running bdist_wheel
  running build
  running build_py
  creating build/lib.linux-x86_64-cpython-313
  copying jnius_config.py -> build/lib.linux-x86_64-cpython-313
  copying setup_sdist.py -> build/lib.linux-x86_64-cpython-313
  creating build/lib.linux-x86_64-cpython-313/jnius
  copying jnius/__init__.py -> build/lib.linux-x86_64-cpython-313/jnius
  copying jnius/env.py -> build/lib.linux-x86_64-cpython-313/jnius
  copying jnius/signatures.py -> build/lib.linux-x86_64-cpython-313/jnius
  copying jnius/reflect.py -> build/lib.linux-x86_64-cpython-313/jnius
  copying jnius/env.py -> build/lib.linux-x86_64-cpython-313/jnius
  copying jnius/__init__.py -> build/lib.linux-x86_64-cpython-313/jnius
  creating build/lib.linux-x86_64-cpython-313/jnius/src/org/jnius
  copying jnius/src/org/jnius/NativeInvocationHandler.class -> build/lib.linux-x86_64-cpython-313/jnius/src/org/jnius
  copying jnius/src/org/jnius/NativeInvocationHandler.java -> build/lib.linux-x86_64-cpython-313/jnius/src/org/jnius
  running build_ext
  warning: jnius/jnius.pyx:102:0: The 'IF' statement is deprecated and will be removed in a future Cython version. Consider using runtime conditions or C macros instead. See https://github.com/cython/cython/issues/4310
  Compiling jnius/jnius.pyx because it changed.
  [1/1] Cythonizing jnius/jnius.pyx
  building 'jnius' extension
  creating build/temp.linux-x86_64-cpython-313/jnius
  gcc -fno-strict-overflow -Wsign-compare -DDYNAMIC_ANNOTATIONS_ENABLED=1 -DNDEBUG -fcf-protection -fexceptions -fcf-protection -fexceptions -fcf-protection -fexceptions -O3 -fPIC -I/usr/lib/jvm/java-21-openjdk/include -I/usr/lib/jvm/java-21-openjdk/include/linux -I/myhome/.cache/pypoetry/virtualenvs/pyjn--CgpPmpQ-py3.13/include -I/usr/include/python3.13 -c jnius/jnius.c -o build/temp.linux-x86_64-cpython-313/jnius/jnius.o
  jnius/jnius.c: In function ‘__pyx_f_5jnius_get_jnienv’:
  jnius/jnius.c:22633:76: error: passing argument 2 of ‘(*__pyx_v_5jnius_jvm)->AttachCurrentThread’ from incompatible pointer type [-Wincompatible-pointer-types]
  22633 |   (void)((__pyx_v_5jnius_jvm[0])->AttachCurrentThread(__pyx_v_5jnius_jvm, (&__pyx_v_env), NULL));
        |                                                                           ~^~~~~~~~~~~~~
        |                                                                            |
        |                                                                            const struct JNINativeInterface_ ***
  jnius/jnius.c:22633:76: note: expected ‘void **’ but argument is of type ‘const struct JNINativeInterface_ ***’
  jnius/jnius.c: In function ‘__pyx_f_5jnius_convert_jstring_to_python’:
  jnius/jnius.c:31064:19: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
  31064 |   __pyx_v_j_chars = (__pyx_v_j_env[0])->GetStringChars(__pyx_v_j_env, __pyx_v_j_string, NULL);
        |                   ^
  jnius/jnius.c: In function ‘__pyx_pf_5jnius_13MetaJavaClass_8resolve_class’:
  jnius/jnius.c:43990:30: error: assignment to ‘jobject’ {aka ‘struct _jobject *’} from incompatible pointer type ‘struct _jobject **’ [-Wincompatible-pointer-types]
  43990 |           (__pyx_v_jargs[0]) = ((jobject *)__pyx_v_classLoader);
        |                              ^
  jnius/jnius.c:43999:30: error: assignment to ‘jobject’ {aka ‘struct _jobject *’} from incompatible pointer type ‘struct _jobject **’ [-Wincompatible-pointer-types]
  43999 |           (__pyx_v_jargs[1]) = __pyx_v_interfaces;
        |                              ^
  jnius/jnius.c: In function ‘__pyx_f_5jnius_create_proxy_instance’:
  jnius/jnius.c:61712:36: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
  61712 |   (__pyx_v_invoke_methods[0]).name = ((char const *)"invoke0");
        |                                    ^
  jnius/jnius.c:61721:41: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
  61721 |   (__pyx_v_invoke_methods[0]).signature = ((char const *)"(Ljava/lang/Object;Ljava/lang/reflect/Method;[Ljava/lang/Object;)Ljava/lang/Object;");
        |                                         ^
  error: command '/usr/bin/gcc' failed with exit code 1
  error: subprocess-exited-with-error
  
  × Building wheel for pyjnius (pyproject.toml) did not run successfully.
  │ exit code: 1
  ╰─> See above for output.
  
  note: This error originates from a subprocess, and is likely not a problem with pip.
  full command: /myhome/.cache/pypoetry/virtualenvs/pyjn--CgpPmpQ-py3.13/bin/python /myhome/.cache/pypoetry/virtualenvs/pyjn--CgpPmpQ-py3.13/lib/python3.13/site-packages/pip/_vendor/pyproject_hooks/_in_process/_in_process.py build_wheel /tmp/tmpcyeovkk5
  cwd: /tmp/pip-req-build-k7mu6v1r
  Building wheel for pyjnius (pyproject.toml) ... error
  ERROR: Failed building wheel for pyjnius
Failed to build pyjnius
ERROR: Failed to build installable wheels for some pyproject.toml based projects (pyjnius)