build: PHP 8 support (#52)

* build: PHP 8 support
* build: update phpunit to ^9.3 for php 8 support

.github/workflows/phpunit.yml

@@ -20,6 +20,7 @@ jobs:
           - "highest"
         php-version:
           - "7.4"
+          - "8.0"
         operating-system:
           - "ubuntu-latest"
 
@@ -45,15 +46,15 @@ jobs:
 
       - name: "Install lowest dependencies"
         if: ${{ matrix.dependencies == 'lowest' }}
-        run: "composer update --prefer-lowest --no-interaction --no-progress --no-suggest"
+        run: "composer update --prefer-lowest --no-interaction --no-progress --no-suggest --ignore-platform-reqs"
 
       - name: "Install highest dependencies"
         if: ${{ matrix.dependencies == 'highest' }}
-        run: "composer update --no-interaction --no-progress --no-suggest"
+        run: "composer update --no-interaction --no-progress --no-suggest --ignore-platform-reqs"
 
       - name: "Install locked dependencies"
         if: ${{ matrix.dependencies == 'locked' }}
-        run: "composer install --no-interaction --no-progress --no-suggest"
+        run: "composer install --no-interaction --no-progress --no-suggest --ignore-platform-reqs"
 
       - name: "Tests"
         run: "vendor/bin/phpunit"

composer.json

@@ -3,7 +3,7 @@
     "description": "PSR Container compatible Symfony Messenger",
     "license": "MIT",
     "require": {
-        "php": "^7.4",
+        "php": "^7.4 || ^8.0",
         "psr/container": "^1.0",
         "symfony/amqp-messenger": "^5.1",
         "symfony/doctrine-messenger": "^5.1",
@@ -19,7 +19,7 @@
         "laminas/laminas-auradi-config": "^2.0",
         "laminas/laminas-pimple-config": "^1.1",
         "laminas/laminas-servicemanager": "^3.4",
-        "phpunit/phpunit": "^9.0",
+        "phpunit/phpunit": "^9.3",
         "psalm/plugin-phpunit": "^0.10.0",
         "psr/log": "^1.1",
         "symfony/console": "^4.4 || ^5.0",