Do not use Cython 3 on build deps

Cython 3 generates code which fails on Python that was built with
assertions enabled. This commit adds the upper bound version until this
issue has been fixed.

CI has been updated to test out this specific scenario.

Signed-off-by: Jordan Borean <jborean93@gmail.com>

Author: jborean93

.github/workflows/ci.yml

@@ -134,6 +134,43 @@ jobs:
         path: ./wheelhouse/*.whl
         name: artifact
 
+  # To catch issues like this https://github.com/pythongssapi/python-gssapi/issues/327
+  assertion_build:
+    needs:
+    - build_sdist
+
+    runs-on: ubuntu-latest
+    steps:
+    - name: Download gssapi sdist
+      uses: actions/download-artifact@v3
+      with:
+        name: artifact
+        path: ./dist
+
+    - name: Compile Python with assertions
+      shell: bash
+      run: |
+        PYTHON_VERSION="3.11.5"
+        wget --quiet "https://www.python.org/ftp/python/${PYTHON_VERSION}/Python-${PYTHON_VERSION}.tar.xz"
+        tar xf "Python-${PYTHON_VERSION}.tar.xz"
+        cd "Python-${PYTHON_VERSION}/"
+        ./configure --with-assertions --prefix "${PWD}/../Python-${PYTHON_VERSION}-build"
+        make
+        make install
+        cd ..
+
+        sudo apt-get update
+        DEBIAN_FRONTEND=noninteractive sudo apt-get -y install krb5-user libkrb5-dev
+
+        GSSAPI_VER="$( find ./dist -type f -name 'gssapi-*.tar.gz' -printf "%f\n" | sed -n 's/gssapi-\(.*\)\.tar\.gz/\1/p' )"
+
+        PATH="${PWD}/Python-${PYTHON_VERSION}-build/bin:${PATH}"
+        python3 -m pip install gssapi=="${GSSAPI_VER}" \
+            --find-links "file://${PWD}/dist" \
+            --verbose
+
+        python3 -c "import gssapi"
+
   linux:
     needs:
     - build_sdist
@@ -257,6 +294,7 @@ jobs:
     name: publish
 
     needs:
+    - assertion_build
     - linux
     - macos
     - windows

pyproject.toml

@@ -1,6 +1,8 @@
 [build-system]
 requires = [
-    "Cython >= 0.29.29, < 4.0.0",  # 0.29.29 includes fixes for Python 3.11
+    # 0.29.29 includes fixes for Python 3.11
+    # Cannot use 3 until https://github.com/cython/cython/issues/5665 is fixed
+    "Cython >= 0.29.29, < 3.0.0",
     "setuptools >= 40.6.0",  # Start of PEP 517 support for setuptools
 ]
 build-backend = "setuptools.build_meta"

setup.py

@@ -274,7 +274,7 @@ def gssapi_modules(lst):
 
 setup(
     name='gssapi',
-    version='1.8.3',
+    version='1.8.4',
     author='The Python GSSAPI Team',
     author_email='jborean93@gmail.com',
     packages=['gssapi', 'gssapi.raw', 'gssapi.raw._enum_extensions',