fix null pointer exception #323

	name: 'pull-request'

	on:
	pull_request:
	branches: [ 'main' ]

	jobs:
	lint:
	runs-on: ubuntu-latest
	env:
	SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
	steps:
	- uses: actions/checkout@v3
	id: code-checkout

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

	- name: Cache Composer packages
	id: composer-cache
	uses: actions/cache@v3
	with:
	path: vendor
	key: ${{ runner.os }}-php-${{ hashFiles('**/composer.lock') }}
	restore-keys: \|
	${{ runner.os }}-php-

	- name: Install dependencies
	if: steps.composer-cache.outputs.cache-hit != 'true'
	id: install-dependencies
	run: composer install --prefer-dist --no-progress --no-suggest

	- name: PHPCS checker
	id: php-codesniffer
	run: make lint

	- uses: act10ns/slack@v1
	with:
	status: ${{ job.status }}
	steps: ${{ toJson(steps) }}
	channel: '#crouton'
	if: failure()

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