Add PHP syntax checks for supported versions (#122)

Author: janedbal

composer.json

@@ -28,6 +28,7 @@
         "ext-libxml": "*",
         "editorconfig-checker/editorconfig-checker": "^10.3.0",
         "ergebnis/composer-normalize": "^2.19",
+        "phpcompatibility/php-compatibility": "^9.3",
         "phpstan/phpstan": "^1.10.63",
         "phpstan/phpstan-phpunit": "^1.1.1",
         "phpstan/phpstan-strict-rules": "^1.2.3",

composer.lock

@@ -22,8 +22,11 @@
 
     <exclude-pattern>tests/data/*</exclude-pattern>
 
-    <config name="installed_paths" value="../../slevomat/coding-standard"/>
+    <config name="installed_paths" value="vendor/slevomat/coding-standard,vendor/phpcompatibility/php-compatibility"/>
     <config name="php_version" value="70200"/>
+    <config name="testVersion" value="7.2-"/>
+
+    <rule ref="PHPCompatibility"/>
 
     <rule ref="Generic.Arrays.DisallowLongArraySyntax"/>
     <rule ref="Generic.Classes.DuplicateClassName"/>