Change warning to error; minor fixes #525

	name: Python Package with caching

	# taken from https://github.com/epassaro/cache-conda-envs

	# cancel any previous running or pending jobs from the same branch
	concurrency:
	group: python-package-conda-cache-${{ github.head_ref }}
	cancel-in-progress: true

	on:
	push:
	branches:
	- '*'
	pull_request:
	branches:
	- '*'
	schedule:
	- cron: '0 0 * * 1'
	workflow_dispatch:

	env:
	CACHE_NUMBER: 0 # increase to reset cache manually

	jobs:
	build:

	strategy:
	matrix:
	include:
	- os: ubuntu-latest
	label: linux-64
	prefix: /usr/share/miniconda3/envs/my-env

	name: ${{ matrix.label }}
	runs-on: ${{ matrix.os }}
	steps:
	- uses: actions/checkout@v2

	- name: Setup Mambaforge
	uses: conda-incubator/setup-miniconda@v2
	with:
	miniforge-variant: Mambaforge
	miniforge-version: latest
	activate-environment: my-env
	use-mamba: true

	- name: Set cache date
	run: echo "DATE=$(date +'%Y%m%d')" >> $GITHUB_ENV

	- uses: actions/cache@v2
	with:
	path: ${{ matrix.prefix }}
	key: ${{ matrix.label }}-conda-${{ hashFiles('environment.yml') }}-${{ env.DATE }}-${{ env.CACHE_NUMBER }}
	id: cache

	- name: Update environment
	run: mamba env update -n my-env -f environment.yml
	if: steps.cache.outputs.cache-hit != 'true'

	- name: Run tests
	shell: bash -l {0}
	run: pytest ./tests

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