[ ci ] ensure we test idris1 againsts latest idris1 and emacs. #250

	## Adapted from The Frex Project.

	name: Idris2 on Ubuntu

	# -- [ When to Act]

	on:
	push:
	branches:
	- '*'
	tags:
	- '*'
	pull_request:
	branches:
	- main

	# -- [ ENV Variables ]

	env:
	SCHEME: scheme

	# -- [ Jobs ]
	jobs:

	## -- [ Initialise Build Environment ]
	build:
	runs-on: ubuntu-latest

	timeout-minutes: 60

	strategy:
	matrix:
	emacs: [27.2, 28.2, 29.3]

	env:
	EMACS_VERSION: ${{ matrix.emacs }}

	## -- [ Steps To Run ]
	steps:

	### -- [ Initialise Variables ]

	- name: Initialise variables
	run: \|
	# Only deploy if the build follows from pushing to main
	echo "$HOME/.idris2/bin" >> $GITHUB_PATH

	### -- [ Cache Idris2 ]

	- name: Cache Idris2
	uses: actions/cache@v3
	id: cache-idris2
	with:
	path: \|
	~/.idris2
	key: ${{ runner.os }}-idris2

	### -- [ Fetch Dependencies ]

	#### -- [ Chez Scheme ]

	- name: Install Chez
	run: \|
	sudo apt-get update
	sudo apt-get install -y chezscheme

	#### -- [ Idris2 ]

	- name: Install Idris2
	if: steps.cache-idris2.outputs.cache-hit != 'true'
	run: \|
	pushd .
	git clone https://github.com/idris-lang/idris2
	cd idris2
	make bootstrap && make install
	popd

	#### -- [ Emacs ]

	- name: Fetch Emacs
	uses: purcell/setup-emacs@master
	with:
	version: ${{ matrix.emacs }}

	### -- [ Checkout the test ]

	- name: Checkout
	uses: actions/checkout@v3

	### -- [ Test ]

	- name: Build and Run
	run: \|
	make clean
	make build
	make test2

	# -- [ EOF ]

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