CI: verify docs are up to date #399

	name: lint
	on: [push, pull_request]
	permissions:
	contents: read # to fetch code (actions/checkout)
	env:
	# note that some tools care only for the name, not the value
	FORCE_COLOR: 1
	jobs:
	lint:
	name: ${{ matrix.python-version }} / tox-${{ matrix.toxenv \|\| '(other)' }}
	timeout-minutes: 10
	runs-on: ubuntu-latest
	strategy:
	fail-fast: false
	matrix:
	toxenv: [lint, docs-lint, pycodestyle]
	python-version: [ "3.10" ]
	include:
	# for actions that want git env, not tox env
	- toxenv: null
	python-version: "3.10"
	steps:
	- uses: actions/checkout@v4
	- name: Using Python ${{ matrix.python-version }}
	uses: actions/setup-python@v5
	with:
	python-version: ${{ matrix.python-version }}
	cache: pip
	- name: Install Dependencies (tox)
	if: ${{ matrix.toxenv }}
	run: \|
	python -m pip install --upgrade pip
	python -m pip install tox
	- run: tox -e ${{ matrix.toxenv }}
	if: ${{ matrix.toxenv }}
	- name: Install Dependencies (non-toxic)
	if: ${{ ! matrix.toxenv }}
	run: \|
	python -m pip install sphinx
	- name: "Update docs"
	if: ${{ ! matrix.toxenv }}
	run: \|
	# this will update docs/source/settings.rst - but will not create html output
	(cd docs && sphinx-build -b "dummy" -d _build/doctrees source "_build/dummy")
	if unclean=$(git status --untracked-files=no --porcelain) && [ -z "$unclean" ]; then
	echo "no uncommitted changes in working tree (as it should be)"
	else
	echo "did you forget to run `make -C docs html`?"
	echo "$unclean"
	exit 2
	fi

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