Update code to PHP 7.3 using rector #20

	name: Tests

	on: [push, pull_request]

	jobs:
	test:
	runs-on: ubuntu-latest
	strategy:
	fail-fast: true
	matrix:
	php: [7.3, 7.4, 8.0, 8.1]
	stability: [prefer-lowest, prefer-stable]

	name: PHP ${{ matrix.php }} - ${{ matrix.stability }}

	steps:
	- name: Checkout code
	uses: actions/checkout@v3

	- name: Setup PHP
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php }}
	extensions: dom, curl, libxml, mbstring, zip, pcntl, pdo, sqlite, pdo_sqlite, bcmath, soap, intl, gd, exif, iconv, imagick, fileinfo
	coverage: none

	- name: Setup problem matchers
	run: \|
	echo "::add-matcher::${{ runner.tool_cache }}/php.json"
	echo "::add-matcher::${{ runner.tool_cache }}/phpunit.json"

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

	- name: Lint files
	run: find src tests -name '*.php' \| xargs -n 1 -P4 php -l

	- name: Install dependencies
	run: composer update --${{ matrix.stability }} --prefer-dist --no-interaction

	- name: Execute tests
	run: vendor/bin/phpunit --fail-on-risky

	- name: Analyse files with phpstan
	run: vendor/bin/phpstan analyse --level 0 src tests

	- name: Analyse files with psalm
	run: vendor/bin/phpstan analyse --level 0 src tests

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