Generate github test matrix from tox

We only want one static list of environments to run unit tests and that list should come from tox.ini

This sets up tox-gh-matrix[1] to dynamically generate the list of test environments for github actions to run. It will allow us to consolidate the list to just one for easier maintenance going forward.

[1] https://github.com/medmunds/tox-gh-matrix

.github/workflows/tests.yaml

@@ -29,25 +29,39 @@ jobs:
         run: poetry install --no-interaction --all-extras
       - name: build package
         run: poetry build
+  # use https://github.com/medmunds/tox-gh-matrix to export tox envlist to GH actions
+  get-tox-envlist:
+    runs-on: ubuntu-latest
+    outputs:
+      envlist: ${{ steps.generate-envlist.outputs.envlist }}
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@v4
+      - name: Install Poetry
+        uses: snok/install-poetry@v1
+      - name: Install dependencies
+        run: poetry install --no-interaction --all-extras
+      - id: generate-envlist
+        run: poetry run tox --gh-matrix
   unit-tests:
     runs-on: ubuntu-latest
     strategy:
       fail-fast: true
       matrix:
-        python: ["3.8", "3.9", "3.10", "3.11", "3.12"]
+        tox: ${{ fromJSON(needs.get-tox-envlist.outputs.envlist) }}
     steps:
       - name: Check out repository
         uses: actions/checkout@v4
       - name: Setup Python
         id: setup-python
         uses: actions/setup-python@v5
         with:
-          python-version: ${{ matrix.python }}
+          python-version: ${{ matrix.tox.python.spec }}
       - name: Install Poetry
         uses: snok/install-poetry@v1
       - name: Install dependencies
         run: poetry install --no-interaction --all-extras
       - name: run python tests
-        run: poetry run tox -e py
+        run: poetry run tox -e ${{ matrix.tox.name }}
       - name: run python test report
         run: poetry run tox -e report

pyproject.toml

@@ -24,14 +24,15 @@ classifiers = [
 "custom" = "template_handler.custom:Custom"
 
 [tool.poetry.dependencies]
-python = ">=3.8,<3.12"
+python = "^3.8"
 
 [tool.poetry.group.dev.dependencies]
 pre-commit = "^3.2.1"
-tox = "^4.0.0"
-pytest = "^7.2.2"
+tox = "^3.23.0"
+pytest = "^7.4.3"
 pytest-cov = "^4.0.0"
-sceptre = ">3.2"
+sceptre = "^4.0"
+tox-gh-matrix = "^0.2"
 
 [build-system]
 requires = ["poetry-core>=1.0.0"]