Require phpspec/prophecy for tests #21

	name: CI
	on: [push, pull_request]
	jobs:
	build:
	strategy:
	matrix:
	operating-system: ['ubuntu-latest']
	php-versions: ['7.2', '7.3', '7.4', '8.0', '8.1']
	runs-on: ${{ matrix.operating-system }}
	steps:
	- name: Checkout
	uses: actions/checkout@v2

	- name: Setup PHP, with composer and extensions
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php-versions }}
	coverage: pcov

	- name: Get composer cache directory
	id: composercache
	run: echo "::set-output name=dir::$(composer config cache-files-dir)"

	- name: Cache composer dependencies
	uses: actions/cache@v2
	with:
	path: ${{ steps.composercache.outputs.dir }}
	# Use composer.json for key, if composer.lock is not committed.
	# key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.json') }}
	key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.lock') }}
	restore-keys: ${{ runner.os }}-composer-

	- name: Check Composer configuration
	run: composer validate --strict

	- name: Install dependencies
	run: composer install --no-progress --prefer-dist --optimize-autoloader

	- name: Run unit tests
	run: vendor/bin/phpunit --coverage-clover=build/logs/clover.xml

Provide feedback