Mark Builder methods as pure #995

	name: "Backwards compatibility check"

	on:
	pull_request:

	jobs:
	bc-check:
	name: "Backwards compatibility check"

	runs-on: "ubuntu-latest"

	steps:
	- name: "Checkout"
	uses: "actions/checkout@v4.2.1"
	with:
	fetch-depth: 0

	- name: "Install PHP"
	uses: "shivammathur/setup-php@2.31.1"
	with:
	php-version: "8.2"
	ini-values: memory_limit=-1
	tools: composer:v2, cs2pr
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

	- name: Get composer cache directory
	id: composer-cache
	run: echo "composer_cache_dir=$(composer global config cache-files-dir)" >> $GITHUB_OUTPUT

	- name: "Cache dependencies"
	uses: "actions/cache@v4.1.1"
	with:
	path: ${{ steps.composer-cache.outputs.composer_cache_dir }}
	key: "php-8.2-bc-break-check-${{ hashFiles('.github/workflows/backwards-compatibility.yml') }}"
	restore-keys: "php-8.2-bc-break-check-"

	# Only necessary until https://github.com/Roave/BackwardCompatibilityCheck/pull/737 gets resolved
	- name: "Configure custom repository"
	run: \|
	echo '{"repositories": [{"type":"vcs","url":"git@github.com:lcobucci/BackwardCompatibilityCheck.git"}]}' > ~/.composer/composer.json

	- name: "Install dependencies"
	# run: composer global require roave/backward-compatibility-check
	run: composer global require "roave/backward-compatibility-check:dev-support-baseline-configuration"

	- name: "BC Check"
	run: \|
	~/.composer/vendor/bin/roave-backward-compatibility-check --from=${{ github.event.pull_request.base.sha }} --format=github-actions

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