Add flake.nix development environment configuration. #20

	# SPDX-FileCopyrightText: 2024 Julien Lambé <julien@themosis.com>
	#
	# SPDX-License-Identifier: CC0-1.0

	name: PHPUnit

	on:
	push:
	branches: [ "main" ]
	pull_request:
	branches: [ "main" ]

	permissions:
	contents: read

	jobs:
	build:
	runs-on: ubuntu-latest

	strategy:
	matrix:
	php-version: ['8.2', '8.3']

	steps:
	- uses: actions/checkout@v4

	- name: Install PHP
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php-version }}
	extensions: none, ctype, curl, dom, json, libxml, mbstring, openssl, phar, tokenizer, xml, xmlwriter
	coverage: xdebug
	tools: none

	- name: Validate composer.json and composer.lock
	run: composer validate --strict

	- name: Cache Composer packages
	id: composer-cache
	uses: actions/cache@v4
	with:
	path: vendor
	key: ${{ runner.os }}-php-${{ hashFiles('**/composer.lock') }}
	restore-keys: \|
	${{ runner.os }}-php-

	- name: Install dependencies
	run: composer install --prefer-dist --no-progress

	- name: Install PHPUnit
	run: composer install --working-dir tools/phpunit --prefer-dist --no-progress

	# Add a test script to composer.json, for instance: "test": "vendor/bin/phpunit"
	# Docs: https://getcomposer.org/doc/articles/scripts.md

	- name: Run test suite
	run: tools/phpunit/vendor/bin/phpunit --coverage-text

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