Exact hessian version of 4DVar-Backprop, as separate module for now #250

	name: Tests

	on: [push]

	env:
	CACHE_NUMBER: 0 # increase to reset cache manually

	jobs:
	build-linux:
	runs-on: ubuntu-latest
	strategy:
	max-parallel: 5
	steps:

	- uses: actions/checkout@v3
	- name: Set up Python 3.10.8
	uses: actions/setup-python@v3
	with:
	python-version: '3.10.8'

	- name: Add conda to system path
	run: \|
	# $CONDA is an environment variable pointing to the root of the miniconda directory
	echo $CONDA/bin >> $GITHUB_PATH
	- name: Set cache date
	run: echo "DATE=$(date +'%Y%m%d')" >> $GITHUB_ENV

	- uses: actions/cache@v2
	with:
	path: /usr/share/miniconda3/envs/base/
	key: conda-${{ hashFiles('environment.yml') }}-${{ env.DATE }}-${{ env.CACHE_NUMBER }}
	id: cache

	- name: Update environment
	run: \|
	conda install conda-libmamba-solver flake8 pytest
	# Slightly awkward way of adding an optional package to our environment
	echo " - pyqg" >> environment.yml
	conda env update --name base --file environment.yml --solver=libmamba
	pip install qgs
	if: steps.cache.outputs.cache-hit != 'true'

	- name: Lint with flake8
	run: \|
	# stop the build if there are Python syntax errors or undefined names
	flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
	# exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
	flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics

	- name: Test with pytest
	run: \|
	python -m pytest

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