issue #16 add PHP 8.0 compatibility

Author: svnldwg

.github/workflows/tests-check.yml

@@ -14,7 +14,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        php: ['7.2', '7.3', '7.4']
+        php: ['7.2', '7.3', '7.4', '8.0']
 
     name: PHP ${{ matrix.php }} Test on ${{ matrix.os }}
     steps:
@@ -44,7 +44,7 @@ jobs:
             ${{ runner.os }}-composer-
 
       - name: Install dependencies
-        run: composer install --prefer-dist --no-progress
+        run: composer update --prefer-dist --no-progress
 
       - name: Tests
         run: composer phpunit

composer.json

@@ -15,7 +15,7 @@
     }
   ],
   "require": {
-    "php": "^7.2",
+    "php": "^7.2 | ^8.0",
     "ext-mbstring": "*",
     "nikic/php-parser": "^4.2.3",
     "phpstan/phpstan": "^0.12.0"