Allow older CS fixer version for PHP versions below 7.4.

.gitignore

@@ -8,7 +8,9 @@
 /.idea
 /vendor
 /.php-cs.cache
+/.php_cs.cache
 /.php-cs-fixer.cache
+/.phpunit.result.cache
 /temp/cache
 /temp/logs
 

.php_cs.dist

@@ -0,0 +1,30 @@
+<?php
+
+// For more information visit the Github repository: https://github.com/FriendsOfPHP/PHP-CS-Fixer
+
+// How to set up PHP-CS-Fixer in PHPStorm:
+// https://hackernoon.com/how-to-configure-phpstorm-to-use-php-cs-fixer-1844991e521f
+
+use PhpCsFixer\Config;
+use PhpCsFixer\Finder;
+
+$fixers = array(
+    '@PSR1' => true,
+    '@PSR2' => true,
+    'array_syntax' => array(
+        'syntax' => 'long',
+    ),
+    'blank_line_after_opening_tag' => true,
+    'method_argument_space' => false,
+);
+
+return Config::create()
+    ->setRiskyAllowed(true)
+    ->setUsingCache(true)
+    ->setRules($fixers)
+    ->setFinder(
+        Finder::create()
+            ->exclude('vendor')
+            ->exclude('vendors')
+            ->in(__DIR__)
+    );

composer.json

@@ -22,7 +22,7 @@
   },
   "require-dev": {
     "ext-json": "*",
-    "friendsofphp/php-cs-fixer": "^v3.49.0",
+    "friendsofphp/php-cs-fixer": "^2.19.3 ||3.49.0",
     "phpunit/phpunit": ">= 5",
     "yoast/phpunit-polyfills": "^1.0"
   },