Switch to tox & explicit list

.github/workflows/ci-supported-pythons.yml

@@ -29,27 +29,48 @@ jobs:
           path: sampleproject
 
     outputs:
-      python-versions: ${{ steps.baipp.outputs.supported_pythons_json_job_matrix_value }}
+      python-versions: ${{ steps.baipp.outputs.supported_pythons_json_array }}
+      # If your matrix consists only of Python versions, you can use the
+      # following, too:
+      # python-versions: ${{ steps.baipp.outputs.supported_pythons_json_job_matrix_value }}
 
   test-package:
     needs: build-package
     runs-on: ubuntu-latest
     strategy:
-      matrix: ${{ fromJson(needs.build-package.outputs.python-versions) }}
+      matrix:
+        # Create matrix from the 'python-versions' output from the build-package
+        # job.
+        python-version: ${{ fromJson(needs.build-package.outputs.python-versions) }}
+
+      # If you set 'python-versions' to
+      # 'supported_pythons_json_job_matrix_value'
+      # above, you would set the matrix like this instead:
+      # matrix: ${{ fromJson(needs.build-package.outputs.python-versions) }}
+
 
     steps:
       - uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
-      - run: pip install pytest
-      - uses: actions/download-artifact@v4
+
+      - name: Download built packages from the build-package job.
+        uses: actions/download-artifact@v4
         with:
           name: Packages
           path: dist
-      - run: pip install dist/*.whl
-      - uses: actions/checkout@v4
-        with:
-          repository: pypa/sampleproject
-      - run: python -Im pytest tests/
+
+      - name: Prepare tests & config
+        run: |
+          # We use tox together with the fast tox-uv plugin.
+          python -Im pip install tox-uv
+
+          # Unpack SDist for tests & config files.
+          tar xf dist/*.tar.gz --strip-components=1
+
+          # Ensure tests run against wheel.
+          rm -rf src
+
+      - run: python -Im tox run --installpkg dist/*.whl -f py$(echo ${{ matrix.python-version }} | tr -d .)
 
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