diff --git a/classes/frontend.php b/classes/frontend.php
index f72a438..0c7f4e2 100644
--- a/classes/frontend.php
+++ b/classes/frontend.php
@@ -44,7 +44,7 @@ class frontend extends \core_availability\frontend {
      *
      * @return array
      */
-    protected function get_javascript_init_params($course, \cm_info $cm = null, \section_info $section = null) {
+    protected function get_javascript_init_params($course, ?\cm_info $cm = null, ?\section_info $section = null) {
         // Change to JS array format and return.
         $jsarray = [];
         $context = \context_course::instance($course->id);
@@ -113,7 +113,7 @@ protected function get_course_roles($context) {
      *
      * @return bool
      */
-    protected function allow_add($course, \cm_info $cm = null, \section_info $section = null) {
+    protected function allow_add($course, ?\cm_info $cm = null, ?\section_info $section = null) {
         return true;
     }
 }
diff --git a/classes/privacy/provider.php b/classes/privacy/provider.php
index 5ff49f1..54e7335 100644
--- a/classes/privacy/provider.php
+++ b/classes/privacy/provider.php
@@ -39,7 +39,7 @@ class provider implements \core_privacy\local\metadata\null_provider {
      *
      * @return string
      */
-    public static function get_reason() : string {
+    public static function get_reason(): string {
         return 'privacy:metadata';
     }
 }
diff --git a/lang/en/availability_role.php b/lang/en/availability_role.php
index d017aa2..dc6bd61 100644
--- a/lang/en/availability_role.php
+++ b/lang/en/availability_role.php
@@ -28,13 +28,13 @@
 $string['description'] = 'Allow only users with a specified course role.';
 $string['error_selectrole'] = 'You must select a role';
 $string['missing'] = '[Missing role]';
-$string['title'] = 'Role';
 $string['pluginname'] = 'Restriction by course role';
 $string['privacy:metadata'] = 'The Restriction by course role plugin does not store any personal data.';
-$string['requires_role'] = 'You are a(n) <em>{$a}</em>';
 $string['requires_notrole'] = 'You are not a(n) <em>{$a}</em>';
+$string['requires_role'] = 'You are a(n) <em>{$a}</em>';
 $string['setting_supportedrolesheading'] = 'Supported roles';
 $string['setting_supportguestrole'] = 'Guest role';
 $string['setting_supportguestrole_desc'] = 'If activated, the availability of activities can be restricted to or forbidden for users that are viewing a course as guest.';
 $string['setting_supportnotloggedinrole'] = 'Not-logged-in role';
 $string['setting_supportnotloggedinrole_desc'] = 'If activated, the availability of activities can be restricted to or forbidden for users that are not logged in.';
+$string['title'] = 'Role';
diff --git a/tests/condition_test.php b/tests/condition_test.php
index 7dfbdb2..dde5e73 100644
--- a/tests/condition_test.php
+++ b/tests/condition_test.php
@@ -33,7 +33,7 @@
  *             on behalf of Alexander Bias, Ulm University <alexander.bias@uni-ulm.de>
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-class condition_test extends \advanced_testcase {
+final class condition_test extends \advanced_testcase {
     /**
      * Load required classes.
      */
@@ -49,7 +49,7 @@ public function setUp(): void {
      * @covers \availability_role\condition::is_available()
      * @covers \availability_role\condition::get_description()
      */
-    public function test_usage() {
+    public function test_usage(): void {
         global $CFG, $USER, $DB;
         $this->resetAfterTest();
         $CFG->enableavailability = true;
@@ -82,7 +82,7 @@ public function test_usage() {
      *
      * @covers \availability_role\condition::save()
      */
-    public function test_save() {
+    public function test_save(): void {
         $structure = (object)['id' => 123];
         $cond = new condition($structure);
         $structure->type = 'role';