added check that niwot.out hasn't changed to github actions #27

	name: CI

	on:
	push:
	branches:
	- master

	pull_request:

	jobs:

	# try to build SIPNET on Windows, Ubuntu, MacOS
	build:
	strategy:
	fail-fast: false
	matrix:
	OS:
	- macos-latest
	- ubuntu-latest
	- ubuntu-20.04
	- windows-latest

	runs-on: ${{ matrix.OS }}

	steps:
	# checkout source code
	- uses: actions/checkout@v2

	# compile sipnet
	- name: compile sipnet
	run: make

	# remove existing test output file
	- name: Remove Niwout Output File
	run: rm Sites/Niwot/niwot.out

	# run single sipnet run
	- name: sipnet on Sites/Niwot/niwot
	run: ./sipnet

	# check output of test
	- name: fail if no niwot output exists
	if: ${{ hashFiles('Sites/Niwot/niwot.out') == '' }}
	run: \|
	echo "::error title={No Output}::Test run for Niwot site failed to produce output"
	exit 1
	# check whether niwot.out has changed
	- name: Check whether niwot.out has changed
	run: \|
	if git diff --exit-code Sites/Niwot/niwot.out; then
	echo "Success: Niwot.out created and has not changed"
	else
	echo "::error title={Output Changed}::The test file niwot.out has changed"
	exit 1
	fi

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