diff --git a/CHANGES.md b/CHANGES.md
index 54cd8bf0..624ee0fe 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 Last release of this plugin is 7.27.1 (9th of nov. 2021).
 
+## [Unreleased]
+- fix(ci): moodle code checker warning and errors #19424.
+
 ## v7.27.1 - 9th nov. 2021
 - Fix "missing ['privacy:metadata']" from @christina-roperto contribution #86
 - Improve the "MathType Moodle Plugins Suite" software development cycle.
diff --git a/classes/moodledbcache.php b/classes/moodledbcache.php
index 38ce26a1..d73e9bd6 100644
--- a/classes/moodledbcache.php
+++ b/classes/moodledbcache.php
@@ -23,9 +23,6 @@
  * @copyright  WIRIS Europe (Maths for more S.L)
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-
-defined('MOODLE_INTERNAL') || die();
-
 class moodledbcache {
 
     private $cachetable;
diff --git a/classes/moodledbjsoncache.php b/classes/moodledbjsoncache.php
index 3db7fba8..278b4a33 100644
--- a/classes/moodledbjsoncache.php
+++ b/classes/moodledbjsoncache.php
@@ -23,9 +23,6 @@
  * @copyright  WIRIS Europe (Maths for more S.L)
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-
-defined('MOODLE_INTERNAL') || die();
-
 class moodledbjsoncache {
 
     private $cachetable;
diff --git a/classes/moodlefilecache.php b/classes/moodlefilecache.php
index f092ec41..628c5bbd 100644
--- a/classes/moodlefilecache.php
+++ b/classes/moodlefilecache.php
@@ -23,9 +23,6 @@
  * @copyright  WIRIS Europe (Maths for more S.L)
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-
-defined('MOODLE_INTERNAL') || die();
-
 class moodlefilecache {
 
     private $cache;
diff --git a/classes/pluginwrapperconfigurationupdater.php b/classes/pluginwrapperconfigurationupdater.php
index 69f46f26..f4c1880d 100644
--- a/classes/pluginwrapperconfigurationupdater.php
+++ b/classes/pluginwrapperconfigurationupdater.php
@@ -29,7 +29,7 @@
 
 require_once($CFG->dirroot . '/filter/wiris/integration/lib/com/wiris/plugin/configuration/ConfigurationUpdater.interface.php');
 
-class filter_wiris_pluginwrapperconfigurationupdater implements com_wiris_plugin_configuration_ConfigurationUpdater{
+class filter_wiris_pluginwrapperconfigurationupdater implements com_wiris_plugin_configuration_ConfigurationUpdater {
 
     private $customconfig;
 
diff --git a/classes/privacy/provider.php b/classes/privacy/provider.php
index d5aaffe5..29395477 100644
--- a/classes/privacy/provider.php
+++ b/classes/privacy/provider.php
@@ -21,11 +21,8 @@
  * @copyright  WIRIS Europe (Maths for more S.L)
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-
 namespace filter_wiris\privacy;
 
-defined('MOODLE_INTERNAL') || die();
-
 /**
  * Privacy Subsystem for filter_wiris implementing null_provider.
  *
diff --git a/db/upgrade.php b/db/upgrade.php
index c800b4b8..6baf208b 100644
--- a/db/upgrade.php
+++ b/db/upgrade.php
@@ -22,9 +22,6 @@
  * @copyright  WIRIS Europe (Maths for more S.L)
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-
-defined('MOODLE_INTERNAL') || die();
-
 function xmldb_filter_wiris_upgrade($oldversion) {
     global $DB, $CFG;
 
diff --git a/lib.php b/lib.php
index 0ea8fd51..2d7232be 100644
--- a/lib.php
+++ b/lib.php
@@ -23,8 +23,6 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
-defined('MOODLE_INTERNAL') || die();
-
 /**
  * Return an array with the position of the tags named $name on $code variable.
  * @param  String  $code       html code.
diff --git a/subfilters/client.php b/subfilters/client.php
index 35db3529..0c9b9346 100644
--- a/subfilters/client.php
+++ b/subfilters/client.php
@@ -24,11 +24,6 @@
  * @copyright  WIRIS Europe (Maths for more S.L)
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-
-
-defined('MOODLE_INTERNAL') || die();
-
-
 class filter_wiris_client extends moodle_text_filter {
 
     /**
diff --git a/subfilters/php.php b/subfilters/php.php
index a68515af..c339f49c 100644
--- a/subfilters/php.php
+++ b/subfilters/php.php
@@ -25,11 +25,6 @@
  * @copyright  WIRIS Europe (Maths for more S.L)
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-
-
-defined('MOODLE_INTERNAL') || die();
-
-
 class filter_wiris_php extends moodle_text_filter {
 
     /**
diff --git a/tests/filter_performance_png_test.php b/tests/filter_performance_png_test.php
index 18335798..7c3af3c1 100644
--- a/tests/filter_performance_png_test.php
+++ b/tests/filter_performance_png_test.php
@@ -22,15 +22,14 @@
  * @copyright  2016
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later.
  */
-
 defined('MOODLE_INTERNAL') || die();
 
 global $CFG;
 require_once($CFG->dirroot . '/filter/wiris/filter.php');
 require_once($CFG->dirroot . '/filter/wiris/integration/lib/com/wiris/system/CallWrapper.class.php');
 
-class filter_wiris_filter_performance_png_testcase extends advanced_testcase
-{   protected $wirisfilter;
+class filter_performance_png_test extends advanced_testcase {
+    protected $wirisfilter;
     protected $safexml;
     protected $xml;
     protected $imagepng;
diff --git a/tests/filter_performance_svg_test.php b/tests/filter_performance_svg_test.php
index 09177f6c..d4b902e6 100644
--- a/tests/filter_performance_svg_test.php
+++ b/tests/filter_performance_svg_test.php
@@ -22,15 +22,14 @@
  * @copyright  2016
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later.
  */
-
 defined('MOODLE_INTERNAL') || die();
 
 global $CFG;
 require_once($CFG->dirroot . '/filter/wiris/filter.php');
 require_once($CFG->dirroot . '/filter/wiris/integration/lib/com/wiris/system/CallWrapper.class.php');
 
-class filter_wiris_filter_performance_svg_testcase extends advanced_testcase
-{   protected $wirisfilter;
+class filter_performance_svg_test extends advanced_testcase {
+    protected $wirisfilter;
     protected $safexml;
     protected $xml;
     protected $image;
diff --git a/tests/filter_without_performance_png_test.php b/tests/filter_without_performance_png_test.php
index 9e9a1b15..af12fa72 100644
--- a/tests/filter_without_performance_png_test.php
+++ b/tests/filter_without_performance_png_test.php
@@ -22,14 +22,13 @@
  * @copyright  2016
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later.
  */
-
 defined('MOODLE_INTERNAL') || die();
 
 global $CFG;
 require_once($CFG->dirroot . '/filter/wiris/filter.php');
 
-class filter_wiris_filter_noperformance_png_testcase extends advanced_testcase
-{   protected $wirisfilter;
+class filter_without_performance_png_test extends advanced_testcase {
+    protected $wirisfilter;
     protected $safexml;
     protected $xml;
     protected $image;
diff --git a/tests/filter_without_performance_svg_test.php b/tests/filter_without_performance_svg_test.php
index 819188e2..e94d9ff8 100644
--- a/tests/filter_without_performance_svg_test.php
+++ b/tests/filter_without_performance_svg_test.php
@@ -22,14 +22,13 @@
  * @copyright  2016
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later.
  */
-
 defined('MOODLE_INTERNAL') || die();
 
 global $CFG;
 require_once($CFG->dirroot . '/filter/wiris/filter.php');
 
-class filter_wiris_filter_noperformance_svg_testcase extends advanced_testcase
-{   protected $wirisfilter;
+class filter_without_performance_svg_test extends advanced_testcase {
+    protected $wirisfilter;
     protected $safexml;
     protected $xml;
     protected $instance;