Remove union types #104

	name: Continuous integration checks

	on:
	# Run on PRs and pushes.
	push:
	pull_request:
	paths-ignore:
	- '**.md'
	- '**.yml'
	- '**.json'
	- '**.xml'
	- '**.neon'
	- '**.lock'
	# Allow manually triggering the workflow.
	workflow_dispatch:

	# Cancels all previous workflow runs for the same branch that have not yet completed.
	concurrency:
	# The concurrency group contains the workflow name and the branch name.
	group: ${{ github.workflow }}-${{ github.ref }}
	cancel-in-progress: true

	jobs:
	phpcs:
	name: PHPCS check on PHP ${{ matrix.php }}
	runs-on: ubuntu-latest
	strategy:
	fail-fast: false
	matrix:
	php: [7.4, 8.0, 8.1, 8.3]

	steps:
	- name: Checkout
	uses: actions/checkout@v4

	- name: PHP setup
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php }}
	coverage: none
	tools: cs2pr

	- name: Install Composer dependencies
	uses: ramsey/composer-install@v2
	with:
	custom-cache-suffix: $(date -u "+%Y-%m")

	- name: Check coding standards using PHPCS
	run: composer test:style -- --report-full --report-checkstyle=./phpcs-report.xml

	- name: Show PHPCS results in PR
	run: cs2pr ./phpcs-report.xml

	phpstan:
	name: PHPStan check
	runs-on: ubuntu-latest
	strategy:
	fail-fast: false
	matrix:
	php: [7.4, 8.0, 8.1, 8.3]

	steps:
	- name: Checkout
	uses: actions/checkout@v4

	- name: PHP setup
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php }}
	coverage: none

	- name: Install Composer dependencies
	uses: ramsey/composer-install@v2
	with:
	custom-cache-suffix: $(date -u "+%Y-%m")gs

	- name: Check code consistency using PHPStan
	run: composer test:types

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