diff --git a/filter/tidy/filter.php b/filter/tidy/filter.php
index 779425352cd..f11aa1f31a1 100644
--- a/filter/tidy/filter.php
+++ b/filter/tidy/filter.php
@@ -1,5 +1,4 @@
 <?php
-
 // This file is part of Moodle - http://moodle.org/
 //
 // Moodle is free software: you can redistribute it and/or modify
@@ -16,50 +15,47 @@
 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
 
 /**
- * HTML  tidy text filter.
+ * HTML tidy text filter.
  *
- * @package    filter
+ * This class looks for text including markup and
+ * applies tidy's repair function to it.
+ * Tidy is a HTML clean and
+ * repair utility, which is currently available for PHP 4.3.x and PHP 5 as a
+ * PECL extension from http://pecl.php.net/package/tidy, in PHP 5 you need only
+ * to compile using the --with-tidy option.
+ * If you don't have the tidy extension installed or don't know, you can enable
+ * or disable this filter, it just won't have any effect.
+ * If you want to know what you can set in $tidyoptions and what their default
+ * values are, see http://php.net/manual/en/function.tidy-get-config.php.
+ *
+ * @package    filter_tidy
  * @subpackage tiny
  * @copyright  2004 Hannes Gassert <hannes at mediagonal dot ch>
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-
-defined('MOODLE_INTERNAL') || die();
-
-// This class looks for text including markup and
-// applies tidy's repair function to it.
-// Tidy is a HTML clean and
-// repair utility, which is currently available for PHP 4.3.x and PHP 5 as a
-// PECL extension from http://pecl.php.net/package/tidy, in PHP 5 you need only
-// to compile using the --with-tidy option.
-// If you don't have the tidy extension installed or don't know, you can enable
-// or disable this filter, it just won't have any effect.
-// If you want to know what you can set in $tidyoptions and what their default
-// values are, see http://php.net/manual/en/function.tidy-get-config.php.
-
 class filter_tidy extends moodle_text_filter {
-    function filter($text, array $options = array()) {
+    #[\Override]
+    public function filter($text, array $options = []) {
+        // Configuration for tidy. Feel free to tune for your needs, e.g. to allow
+        // proprietary markup.
+        $tidyoptions = [
+            'output-xhtml' => true,
+            'show-body-only' => true,
+            'tidy-mark' => false,
+            'drop-proprietary-attributes' => true,
+            'drop-empty-paras' => true,
+            'indent' => true,
+            'quiet' => true,
+        ];
 
-    /// Configuration for tidy. Feel free to tune for your needs, e.g. to allow
-    /// proprietary markup.
-        $tidyoptions = array(
-                 'output-xhtml' => true,
-                 'show-body-only' => true,
-                 'tidy-mark' => false,
-                 'drop-proprietary-attributes' => true,
-                 'drop-empty-paras' => true,
-                 'indent' => true,
-                 'quiet' => true,
-        );
-
-    /// Do a quick check using strpos to avoid unnecessary work
+        // Do a quick check using strpos to avoid unnecessary work.
         if (strpos($text, '<') === false) {
             return $text;
         }
 
 
-    /// If enabled: run tidy over the entire string
-        if (function_exists('tidy_repair_string')){
+        // If enabled: run tidy over the entire string.
+        if (function_exists('tidy_repair_string')) {
             $currentlocale = \core\locale::get_locale();
             try {
                 $text = tidy_repair_string($text, $tidyoptions, 'utf8');
diff --git a/filter/tidy/tests/filter_tidy_test.php b/filter/tidy/tests/filter_tidy_test.php
index f62e0199cdb..56b03a29d5e 100644
--- a/filter/tidy/tests/filter_tidy_test.php
+++ b/filter/tidy/tests/filter_tidy_test.php
@@ -108,5 +108,4 @@ final class filter_tidy_test extends \advanced_testcase {
             ],
         ];
     }
-
 }