4 threads #2270

	name: Mutation Testing

	on:
	push:
	# Prevent duplicate jobs on Dependabot PRs that interfere with automerge.
	branches-ignore:
	- 'dependabot/**'
	pull_request:

	jobs:
	tests:
	runs-on: ubuntu-22.04

	name: Mutation Testing
	steps:
	- name: Checkout code
	uses: actions/checkout@v4

	- name: Setup PHP
	uses: shivammathur/setup-php@v2
	with:
	php-version: 8.2
	tools: composer:v2
	coverage: pcov

	- name: Install dependencies
	run: \|
	nproc
	composer install --no-progress --no-suggest --no-interaction

	- name: Run Infection for added files only
	if: github.event_name == 'pull_request'
	run: \|
	git fetch --depth=1 origin $GITHUB_BASE_REF
	# nproc returns 4 threads on GitHub Actions.
	composer mutation-diff-lines

	- name: Run Infection for all files
	if: github.event_name == 'push'
	env:
	INFECTION_DASHBOARD_API_KEY: ${{ secrets.INFECTION_DASHBOARD_API_KEY }}
	run: composer mutation

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