diff --git a/backup/moodle2/backup_moodleoverflow_stepslib.php b/backup/moodle2/backup_moodleoverflow_stepslib.php
index 8c803d438c..aa56787799 100644
--- a/backup/moodle2/backup_moodleoverflow_stepslib.php
+++ b/backup/moodle2/backup_moodleoverflow_stepslib.php
@@ -39,16 +39,14 @@ class backup_moodleoverflow_activity_structure_step extends backup_activity_stru
      * @return backup_nested_element
      */
     protected function define_structure() {
-
         // To know if we are including userinfo.
         $userinfo = $this->get_setting_value('userinfo');
 
         // Define the root element describing the moodleoverflow instance.
         $moodleoverflow = new backup_nested_element('moodleoverflow', ['id'], [
-            'name', 'intro', 'introformat', 'maxbytes', 'maxattachments', 'timecreated', 'timemodified',
-            'forcesubscribe', 'trackingtype', 'ratingpreference', 'coursewidereputation', 'allowrating',
-            'allowreputation', 'allownegativereputation', 'grademaxgrade', 'gradescalefactor', 'gradecat',
-            'anonymous', 'allowmultiplemarks', ]);
+            'name', 'intro', 'introformat', 'maxbytes', 'maxattachments', 'timecreated', 'timemodified', 'forcesubscribe',
+            'trackingtype', 'ratingpreference', 'coursewidereputation', 'allowrating', 'allowreputation', 'allownegativereputation',
+            'grademaxgrade', 'gradescalefactor', 'gradecat', 'anonymous', 'allowmultiplemarks', ]);
 
         // Define each element separated.
         $discussions = new backup_nested_element('discussions');
@@ -56,24 +54,20 @@ protected function define_structure() {
             'name', 'firstpost', 'userid', 'timestart', 'timemodified', 'usermodified', ]);
 
         $posts = new backup_nested_element('posts');
-        $post = new backup_nested_element('post', ['id'], [
-            'parent', 'userid', 'created', 'modified',
-            'message', 'messageformat', 'attachment', 'mailed', 'reviewed', 'timereviewed', ]);
+        $post = new backup_nested_element('post', ['id'], ['parent', 'userid', 'created', 'modified', 'message',
+            'messageformat', 'attachment', 'mailed', 'reviewed', 'timereviewed', ]);
 
         $ratings = new backup_nested_element('ratings');
-        $rating = new backup_nested_element('rating', ['id'], [
-            'userid', 'rating', 'firstrated', 'lastchanged', ]);
+        $rating = new backup_nested_element('rating', ['id'], ['userid', 'rating', 'firstrated', 'lastchanged']);
 
         $discussionsubs = new backup_nested_element('discuss_subs');
-        $discussionsub = new backup_nested_element('discuss_sub', ['id'], [
-            'userid', 'preference', ]);
+        $discussionsub = new backup_nested_element('discuss_sub', ['id'], ['userid', 'preference']);
 
         $subscriptions = new backup_nested_element('subscriptions');
         $subscription = new backup_nested_element('subscription', ['id'], ['userid']);
 
         $readposts = new backup_nested_element('readposts');
-        $read = new backup_nested_element('read', ['id'], [
-            'userid', 'discussionid', 'postid', 'firstread', 'lastread', ]);
+        $read = new backup_nested_element('read', ['id'], ['userid', 'discussionid', 'postid', 'firstread', 'lastread']);
 
         $grades = new backup_nested_element('grades');
         $grade = new backup_nested_element('grade', ['id'], ['userid', 'grade']);
@@ -100,6 +94,9 @@ protected function define_structure() {
         $moodleoverflow->add_child($readposts);
         $readposts->add_child($read);
 
+        $moodleoverflow->add_child($grades);
+        $grades->add_child($grade);
+
         $moodleoverflow->add_child($tracking);
         $tracking->add_child($track);
 
diff --git a/classes/manager/mail_manager.php b/classes/manager/mail_manager.php
index 9fc7118b0a..e822a01719 100644
--- a/classes/manager/mail_manager.php
+++ b/classes/manager/mail_manager.php
@@ -65,7 +65,7 @@ class mail_manager {
      * @return bool
      */
     public static function moodleoverflow_send_mails(): bool {
-        global $DB, $CFG, $PAGE;
+        global $CFG, $DB, $PAGE;
 
         // Get the course object of the top level site.
         $site = get_site();
@@ -86,10 +86,8 @@ public static function moodleoverflow_send_mails(): bool {
         $moodleoverflows = [];
         $courses = [];
         $coursemodules = [];
-        $subscribedusers = [];
 
-        // Posts older than x days will not be mailed.
-        // This will avoid problems with the cron not ran for a long time.
+        // Posts older than x days will not be mailed. This will avoid problems with the cron not ran for a long time.
         $timenow = time();
         $endtime = $timenow - get_config('moodleoverflow', 'maxeditingtime');
         $starttime = $endtime - (get_config('moodleoverflow', 'maxmailingtime') * 60 * 60);
@@ -102,7 +100,6 @@ public static function moodleoverflow_send_mails(): bool {
                 mtrace('Errors occurred while trying to mark some posts as being mailed.');
                 return false;
             }
-
             // Loop through all posts to be mailed.
             foreach ($posts as $postid => $post) {
                 self::check_post($post, $mailcount, $users, $discussions, $errorcount, $posts, $postid,
@@ -126,10 +123,10 @@ public static function moodleoverflow_send_mails(): bool {
                 $userto->markposts = [];
 
                 // Cache the capabilities of the user.
-                cron_setup_user($userto);
+                $CFG->branch >= 402 ? \core\cron::setup_user($userto) : cron_setup_user($userto);
 
                 // Reset the caches.
-                foreach ($coursemodules as $moodleoverflowid => $unused) {
+                foreach ($coursemodules as $moodleoverflowid) {
                     $coursemodules[$moodleoverflowid]->cache = new stdClass();
                     $coursemodules[$moodleoverflowid]->cache->caps = [];
                     unset($coursemodules[$moodleoverflowid]->uservisible);
@@ -137,7 +134,6 @@ public static function moodleoverflow_send_mails(): bool {
 
                 // Loop through all posts of this users.
                 foreach ($posts as $post) {
-
                     self::send_post($userto, $post, $coursemodules, $errorcount,
                         $discussions, $moodleoverflows, $courses, $mailcount, $users, $site, $textout, $htmlout);
                 }
@@ -148,18 +144,13 @@ public static function moodleoverflow_send_mails(): bool {
         }
 
         // Check for all posts whether errors occurred.
-        if ($posts) {
-
-            // Loop through all posts.
-            foreach ($posts as $post) {
-
-                // Tracing information.
-                mtrace($mailcount[$post->id] . " users were sent post $post->id");
+        foreach ($posts as $post) {
+            // Tracing information.
+            mtrace($mailcount[$post->id] . " users were sent post $post->id");
 
-                // Mark the posts with errors in the database.
-                if ($errorcount[$post->id]) {
-                    $DB->set_field('moodleoverflow_posts', 'mailed', self::MOODLEOVERFLOW_MAILED_ERROR, ['id' => $post->id]);
-                }
+            // Mark the posts with errors in the database.
+            if ($errorcount[$post->id]) {
+                $DB->set_field('moodleoverflow_posts', 'mailed', self::MOODLEOVERFLOW_MAILED_ERROR, ['id' => $post->id]);
             }
         }
 
@@ -232,7 +223,6 @@ public static function moodleoverflow_mark_old_posts_as_mailed($endtime) {
      * @param stdClass $user
      */
     public static function moodleoverflow_minimise_user_record(stdClass $user) {
-
         // Remove all information for the mail generation that are not needed.
         unset($user->institution);
         unset($user->department);
@@ -268,61 +258,31 @@ public static function moodleoverflow_minimise_user_record(stdClass $user) {
     private static function check_post($post, array &$mailcount, array &$users, array &$discussions, array &$errorcount,
                                        array &$posts, int $postid, array &$moodleoverflows, array &$courses,
                                        array &$coursemodules) {
-        global $DB;
         // Check the cache if the discussion exists.
         $discussionid = $post->discussion;
-        if (!isset($discussions[$discussionid])) {
-            // Retrieve the discussion from the database.
-            $discussion = $DB->get_record('moodleoverflow_discussions', ['id' => $post->discussion]);
-
-            // If there is a record, update the cache. Else ignore the post.
-            if ($discussion) {
-                $discussions[$discussionid] = $discussion;
-                subscriptions::fill_subscription_cache($discussion->moodleoverflow);
-                subscriptions::fill_discussion_subscription_cache($discussion->moodleoverflow);
-            } else {
-                mtrace('Could not find discussion ' . $discussionid);
-                unset($posts[$postid]);
-                return;
-            }
+        if (!self::cache_record('moodleoverflow_discussions', $discussionid, $discussions,
+                                'Could not find discussion ', $posts, $postid, true)) {
+            return;
         }
 
         // Retrieve the connected moodleoverflow instance from the database.
         $moodleoverflowid = $discussions[$discussionid]->moodleoverflow;
-        if (!isset($moodleoverflows[$moodleoverflowid])) {
-
-            // Retrieve the record from the database and update the cache.
-            $moodleoverflow = $DB->get_record('moodleoverflow', ['id' => $moodleoverflowid]);
-            if ($moodleoverflow) {
-                $moodleoverflows[$moodleoverflowid] = $moodleoverflow;
-            } else {
-                mtrace('Could not find moodleoverflow ' . $moodleoverflowid);
-                unset($posts[$postid]);
-                return;
-            }
+        if (!self::cache_record('moodleoverflow', $moodleoverflowid, $moodleoverflows,
+                          'Could not find moodleoverflow ', $posts, $postid, false)) {
+            return;
         }
 
         // Retrieve the connected courses from the database.
         $courseid = $moodleoverflows[$moodleoverflowid]->course;
-        if (!isset($courses[$courseid])) {
-
-            // Retrieve the record from the database and update the cache.
-            $course = $DB->get_record('course', ['id' => $courseid]);
-            if ($course) {
-                $courses[$courseid] = $course;
-            } else {
-                mtrace('Could not find course ' . $courseid);
-                unset($posts[$postid]);
-                return;
-            }
+        if (!self::cache_record('course', $courseid, $courses,
+                                'Could not find course ', $posts, $postid, false)) {
+            return;
         }
 
         // Retrieve the connected course modules from the database.
         if (!isset($coursemodules[$moodleoverflowid])) {
-
             // Retrieve the coursemodule and update the cache.
-            $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflowid, $courseid);
-            if ($cm) {
+            if ($cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflowid, $courseid)) {
                 $coursemodules[$moodleoverflowid] = $cm;
             } else {
                 mtrace('Could not find course module for moodleoverflow ' . $moodleoverflowid);
@@ -333,14 +293,12 @@ private static function check_post($post, array &$mailcount, array &$users, arra
 
         // Cache subscribed users of each moodleoverflow.
         if (!isset($subscribedusers[$moodleoverflowid])) {
-
             // Retrieve the context module.
             $modulecontext = context_module::instance($coursemodules[$moodleoverflowid]->id);
 
             // Retrieve all subscribed users.
             $mid = $moodleoverflows[$moodleoverflowid];
-            $subusers = subscriptions::get_subscribed_users($mid, $modulecontext, 'u.*', true);
-            if ($subusers) {
+            if ($subusers = subscriptions::get_subscribed_users($mid, $modulecontext, 'u.*', true)) {
                 // Loop through all subscribed users.
                 foreach ($subusers as $postuser) {
                     // Save the user into the cache.
@@ -361,6 +319,39 @@ private static function check_post($post, array &$mailcount, array &$users, arra
         $errorcount[$postid] = 0;
     }
 
+    /**
+     * Helper function for check_post(). Caches the a record exists in the database and caches the record if needed.
+     * @param string $table
+     * @param int $id
+     * @param array $cache
+     * @param string $errorMessage
+     * @param array $posts
+     * @param int $postid
+     * @param bool $fillsubscache    If the subscription cache is being filled (only when checking discussion cache)
+     * @return bool
+     * @throws \dml_exception
+     */
+    private static function cache_record($table, $id, &$cache, $errormessage, &$posts, $postid, $fillsubscache) {
+        global $DB;
+        // Check if cache if an record exists already in the cache.
+        if (!isset($cache[$id])) {
+            // If there is a record in the database, update the cache. Else ignore the post.
+            if ($record = $DB->get_record($table, ['id' => $id])) {
+                $cache[$id] = $record;
+                if ($fillsubscache) {
+                    subscriptions::fill_subscription_cache($record->moodleoverflow);
+                    subscriptions::fill_discussion_subscription_cache($record->moodleoverflow);
+                }
+            } else {
+                mtrace($errormessage . $id);
+                unset($posts[$postid]);
+                return false;
+            }
+        }
+        return true;
+    }
+
+
     /**
      * Send the Mail with information of the post depending on theinformation available.
      * E.g. anonymous post do not include names, users who want resumes do not get single mails.
@@ -427,11 +418,8 @@ private static function send_post($userto, $post, array &$coursemodules, array &
         }
 
         // Check whether the user is subscribed to the discussion.
-        $iscm = $coursemodules[$moodleoverflow->id];
         $uid = $userto->id;
-        $did = $post->discussion;
-        $issubscribed = subscriptions::is_subscribed($uid, $moodleoverflow, $modulecontext, $did);
-        if (!$issubscribed) {
+        if (!subscriptions::is_subscribed($uid, $moodleoverflow, $modulecontext, $post->discussion)) {
             return;
         }
 
@@ -464,7 +452,7 @@ private static function send_post($userto, $post, array &$coursemodules, array &
         }
 
         // Setup roles and languages.
-        cron_setup_user($userto, $course);
+        $CFG->branch >= 402 ? \core\cron::setup_user($userto, $course) : cron_setup_user($userto, $course);
 
         // Cache the users capability to view full names.
         if (!isset($userto->viewfullnames[$moodleoverflow->id])) {
@@ -522,16 +510,7 @@ private static function send_post($userto, $post, array &$coursemodules, array &
         }
 
         // Format the data.
-        $data = new moodleoverflow_email(
-            $course,
-            $cm,
-            $moodleoverflow,
-            $discussion,
-            $post,
-            $userfrom,
-            $userto,
-            $canreply
-        );
+        $data = new moodleoverflow_email($course, $cm, $moodleoverflow, $discussion, $post, $userfrom, $userto, $canreply);
 
         // Retrieve the unsubscribe-link.
         $userfrom->customheaders[] = sprintf('List-Unsubscribe: <%s>', $data->get_unsubscribediscussionlink());
@@ -557,7 +536,6 @@ private static function send_post($userto, $post, array &$coursemodules, array &
 
         // Check whether the post is a reply.
         if ($post->parent) {
-
             // Add a reply header.
             $parentid = generate_email_messageid(hash('sha256', $post->parent . 'to' . $userto->id));
             $userfrom->customheaders[] = "In-Reply-To: $parentid";
diff --git a/classes/ratings.php b/classes/ratings.php
index 8756545d21..f664aa735d 100644
--- a/classes/ratings.php
+++ b/classes/ratings.php
@@ -42,40 +42,29 @@ class ratings {
      * @param int    $postid
      * @param int    $rating
      * @param object $cm
-     * @param null   $userid
+     * @param int   $userid
      *
      * @return bool|int
      */
-    public static function moodleoverflow_add_rating($moodleoverflow, $postid, $rating, $cm, $userid = null) {
-        global $DB, $USER, $SESSION;
-
-        // Has a user been submitted?
-        if (!isset($userid)) {
-            $userid = $USER->id;
-        }
+    public static function moodleoverflow_add_rating($moodleoverflow, $postid, $rating, $cm, $userid) {
+        global $DB;
 
         // Is the submitted rating valid?
         $possibleratings = [RATING_NEUTRAL, RATING_DOWNVOTE, RATING_UPVOTE, RATING_SOLVED,
             RATING_HELPFUL, RATING_REMOVE_DOWNVOTE, RATING_REMOVE_UPVOTE,
             RATING_REMOVE_SOLVED, RATING_REMOVE_HELPFUL, ];
-        if (!in_array($rating, $possibleratings)) {
-            throw new moodle_exception('invalidratingid', 'moodleoverflow');
-        }
+        moodleoverflow_throw_exception_with_check(!in_array($rating, $possibleratings), 'invalidratingid');
 
-        // Get the related discussion.
-        if (!$post = $DB->get_record('moodleoverflow_posts', ['id' => $postid])) {
-            throw new moodle_exception('invalidparentpostid', 'moodleoverflow');
-        }
+        // Get the related post.
+        $post = moodleoverflow_get_record_or_exception('moodleoverflow_posts', ['id' => $postid], 'invalidparentpostid');
 
         // Check if the post belongs to a discussion.
-        if (!$discussion = $DB->get_record('moodleoverflow_discussions', ['id' => $post->discussion])) {
-            throw new moodle_exception('notpartofdiscussion', 'moodleoverflow');
-        }
+        $discussion = moodleoverflow_get_record_or_exception('moodleoverflow_discussions', ['id' => $post->discussion],
+                                                   'notpartofdiscussion');
 
         // Get the related course.
-        if (!$course = $DB->get_record('course', ['id' => $moodleoverflow->course])) {
-            throw new moodle_exception('invalidcourseid');
-        }
+        $course = moodleoverflow_get_record_or_exception('course', ['id' => $moodleoverflow->course],
+                                                         'invalidcourseid', '*', true);
 
         // Are multiple marks allowed?
         $markssetting = $DB->get_record('moodleoverflow', ['id' => $moodleoverflow->id], 'allowmultiplemarks');
@@ -86,39 +75,25 @@ public static function moodleoverflow_add_rating($moodleoverflow, $postid, $rati
         $coursecontext = \context_course::instance($course->id);
 
         // Redirect the user if capabilities are missing.
-        $canrate = self::moodleoverflow_user_can_rate($post, $modulecontext, $userid);
-        if (!$canrate) {
+        if (!self::moodleoverflow_user_can_rate($post, $modulecontext, $userid)) {
 
             // Catch unenrolled users.
-            if (!isguestuser() && !is_enrolled($coursecontext)) {
-                $SESSION->wantsurl = qualified_me();
-                $SESSION->enrolcancel = get_local_referer(false);
-                redirect(new \moodle_url('/enrol/index.php', [
-                    'id' => $course->id,
-                    'returnurl' => '/mod/moodleoverflow/view.php?m' . $moodleoverflow->id,
-                ]), get_string('youneedtoenrol'));
-            }
+            $returnurl = '/mod/moodleoverflow/view.php?m' . $moodleoverflow->id;
+            moodleoverflow_catch_unenrolled_user($coursecontext, $course->id, $returnurl);
 
             // Notify the user, that he can not post a new discussion.
             throw new moodle_exception('noratemoodleoverflow', 'moodleoverflow');
         }
 
         // Make sure post author != current user, unless they have permission.
-        if (($post->userid == $userid) && !
-            (($rating == RATING_SOLVED || $rating == RATING_REMOVE_SOLVED) &&
-                has_capability('mod/moodleoverflow:marksolved', $modulecontext))
-        ) {
-            throw new moodle_exception('rateownpost', 'moodleoverflow');
-        }
+        $authorcheck = ($post->userid == $userid) && !(($rating == RATING_SOLVED || $rating == RATING_REMOVE_SOLVED) &&
+                                                        has_capability('mod/moodleoverflow:marksolved', $modulecontext));
+        moodleoverflow_throw_exception_with_check($authorcheck, 'rateownpost');
 
         // Check if we are removing a mark.
         if (in_array($rating / 10, $possibleratings)) {
-
-            if (!get_config('moodleoverflow', 'allowratingchange')) {
-                throw new moodle_exception('noratingchangeallowed', 'moodleoverflow');
-
-                return false;
-            }
+            moodleoverflow_get_config_or_exception('moodleoverflow', 'allowratingchange',
+                                                   'noratingchangeallowed', 'moodleoverflow');
 
             // Delete the rating.
             return self::moodleoverflow_remove_rating($postid, $rating / 10, $userid, $modulecontext);
@@ -129,16 +104,13 @@ public static function moodleoverflow_add_rating($moodleoverflow, $postid, $rati
 
         // Mark a post as solution or as helpful.
         if ($rating == RATING_SOLVED || $rating == RATING_HELPFUL) {
+            // Make sure that a helpful mark is made by the user who started the discussion.
+            $isnotstartuser = $rating == RATING_HELPFUL && $userid != $discussion->userid;
+            moodleoverflow_throw_exception_with_check($isnotstartuser, 'nostartuser');
 
-            // Check if the current user is the startuser.
-            if ($rating == RATING_HELPFUL && $userid != $discussion->userid) {
-                throw new moodle_exception('notstartuser', 'moodleoverflow');
-            }
-
-            // Check if the current user is a teacher.
-            if ($rating == RATING_SOLVED && !has_capability('mod/moodleoverflow:marksolved', $modulecontext)) {
-                throw new moodle_exception('notteacher', 'moodleoverflow');
-            }
+            // Make sure that a solution mark is made by a teacher (or someone with the right capability).
+            $isnotteacher = $rating == RATING_SOLVED && !has_capability('mod/moodleoverflow:marksolved', $modulecontext);
+            moodleoverflow_throw_exception_with_check($isnotteacher, 'notteacher');
 
             // Check if multiple marks are not enabled.
             if (!$multiplemarks) {
@@ -154,27 +126,20 @@ public static function moodleoverflow_add_rating($moodleoverflow, $postid, $rati
                     return self::moodleoverflow_update_rating_record($post->id, $rating, $userid, $otherrating->id, $modulecontext);
 
                 } else {
-                    $mid = $moodleoverflow->id;
-
-                    return self::moodleoverflow_add_rating_record($mid, $discussion->id, $post->id,
+                    return self::moodleoverflow_add_rating_record($moodleoverflow->id, $discussion->id, $post->id,
                                                                   $rating, $userid, $modulecontext);
                 }
-
             } else {
                 // If multiplemarks are allowed, only create a new rating.
-                $mid = $moodleoverflow->id;
-                return self::moodleoverflow_add_rating_record($mid, $discussion->id, $post->id, $rating, $userid, $modulecontext);
+                return self::moodleoverflow_add_rating_record($moodleoverflow->id, $discussion->id, $post->id,
+                                                              $rating, $userid, $modulecontext);
             }
         }
 
         // Update an rating record.
         if ($oldrating['normal']) {
-
-            if (!get_config('moodleoverflow', 'allowratingchange')) {
-                throw new moodle_exception('noratingchangeallowed', 'moodleoverflow');
-
-                return false;
-            }
+            moodleoverflow_get_config_or_exception('moodleoverflow', 'allowratingchange',
+                                                   'noratingchangeallowed', 'moodleoverflow');
 
             // Check if the rating can still be changed.
             if (!self::moodleoverflow_can_be_changed($postid, $oldrating['normal']->rating, $userid)) {
@@ -186,10 +151,8 @@ public static function moodleoverflow_add_rating($moodleoverflow, $postid, $rati
         }
 
         // Create a new rating record.
-        $mid = $moodleoverflow->id;
-        $did = $post->discussion;
-
-        return self::moodleoverflow_add_rating_record($mid, $did, $postid, $rating, $userid, $modulecontext);
+        return self::moodleoverflow_add_rating_record($moodleoverflow->id, $post->discussion, $postid,
+                                                      $rating, $userid, $modulecontext);
     }
 
     /**
@@ -197,24 +160,16 @@ public static function moodleoverflow_add_rating($moodleoverflow, $postid, $rati
      * Whether within a course or an instance is decided by the settings.
      *
      * @param int  $moodleoverflowid
-     * @param null $userid
+     * @param int $userid
      * @param bool $forcesinglerating If true you only get the reputation for the given $moodleoverflowid,
      * even if coursewidereputation = true
      *
      * @return int
      */
-    public static function moodleoverflow_get_reputation($moodleoverflowid, $userid = null, $forcesinglerating = false) {
-        global $DB, $USER;
-
-        // Get the user id.
-        if (!isset($userid)) {
-            $userid = $USER->id;
-        }
-
+    public static function moodleoverflow_get_reputation($moodleoverflowid, $userid, $forcesinglerating = false) {
         // Check the moodleoverflow instance.
-        if (!$moodleoverflow = $DB->get_record('moodleoverflow', ['id' => $moodleoverflowid])) {
-            throw new moodle_exception('invalidmoodleoverflowid', 'moodleoverflow');
-        }
+        $moodleoverflow = moodleoverflow_get_record_or_exception('moodleoverflow', ['id' => $moodleoverflowid],
+                                                                 'invalidmoodleoverflowid');
 
         // Check whether the reputation can be summed over the whole course.
         if ($moodleoverflow->coursewidereputation && !$forcesinglerating) {
@@ -244,111 +199,43 @@ public static function moodleoverflow_sort_answers_by_ratings($posts) {
         if ($posts[array_key_first($posts)]->ratingpreference == 1) {
             $solutionspreferred = true;
         }
+        // Build array groups for different types of answers (solved and helpful, only solved/helpful, unmarked).
+        $solvedhelpfulposts = [];
+        $solvedposts = [];
+        $helpfulposts = [];
+        $unmarkedposts = [];
 
-        // Sort the answer posts by ratings.
-        // Build groups of different types of answers (Solved and helpful, only solved/helpful, other).
+        // Sort the answer posts by ratings..
         // markedsolved == 1 means the post is marked as solved.
         // markedhelpful == 1 means the post is marked as helpful.
-        // If a group is complete, sort the group.
-        $index = 1;
-        $startsolvedandhelpful = 1;
-        $startsolved = 1;
-        $starthelpful = 1;
-        $startother = 1;
-        // Solved and helpful posts are first.
+        // Step 1: Iterate trough the answerposts and assign each post to a group.
         foreach ($answerposts as $post) {
-            if ($post->markedsolution > 0 && $post->markedhelpful > 0) {
-                $sortedposts[$index] = $post;
-                $index++;
-            }
-        }
-        // Update the indices and sort the group by votes.
-        if ($index > $startsolvedandhelpful) {
-            $startsolved = $index;
-            $starthelpful = $index;
-            $startother = $index;
-            self::moodleoverflow_quicksort_posts($sortedposts, $startsolvedandhelpful, $index - 1, 'votesdifference');
-            self::moodleoverflow_check_equal_votes($sortedposts, $startsolvedandhelpful, $index - 1);
-        }
-
-        // Check if solutions are preferred.
-        if ($solutionspreferred) {
-
-            // Build the group of only solved posts.
-            foreach ($answerposts as $post) {
-                if ($post->markedsolution > 0 && $post->markedhelpful == 0) {
-                    $sortedposts[$index] = $post;
-                    $index++;
-                }
-            }
-            // Update the indices and sort the group by votes.
-            if ($index > $startsolved) {
-                $starthelpful = $index;
-                $startother = $index;
-                self::moodleoverflow_quicksort_posts($sortedposts, $startsolved, $index - 1, 'votesdifference');
-                self::moodleoverflow_check_equal_votes($sortedposts, $startsolved, $index - 1);
-            }
-
-            // Build the group of only helpful posts.
-            foreach ($answerposts as $post) {
-                if ($post->markedsolution == 0 && $post->markedhelpful > 0) {
-                    $sortedposts[$index] = $post;
-                    $index++;
-                }
-            }
-            // Update the indices and sort the group by votes.
-            if ($index > $starthelpful) {
-                $startother = $index;
-                self::moodleoverflow_quicksort_posts($sortedposts, $starthelpful, $index - 1, 'votesdifference');
-                self::moodleoverflow_check_equal_votes($sortedposts, $starthelpful, $index - 1);
-            }
-        } else {
-
-            // Build the group of only helpful posts.
-            foreach ($answerposts as $post) {
-                if ($post->markedsolution == 0 && $post->markedhelpful > 0) {
-                    $sortedposts[$index] = $post;
-                    $index++;
+            if ($post->markedsolution > 0) {
+                if ($post->markedhelpful > 0) {
+                    $solvedhelpfulposts[] = $post;
+                } else {
+                    $solvedposts[] = $post;
                 }
-            }
-            // Update the indices and sort the group by votes.
-            if ($index > $starthelpful) {
-                $startsolved = $index;
-                $startother = $index;
-                self::moodleoverflow_quicksort_posts($sortedposts, $starthelpful, $index - 1, 'votesdifference');
-                self::moodleoverflow_check_equal_votes($sortedposts, $starthelpful, $index - 1);
-            }
-
-            // Build the group of only solved posts.
-            foreach ($answerposts as $post) {
-                if ($post->markedsolution > 0 && $post->markedhelpful == 0) {
-                    $sortedposts[$index] = $post;
-                    $index++;
+            } else {
+                if ($post->markedhelpful > 0) {
+                    $helpfulposts[] = $post;
+                } else {
+                    $unmarkedposts[] = $post;
                 }
             }
-            // Update the indices and sort the group by votes.
-            if ($index > $startsolved) {
-                $startother = $index;
-                self::moodleoverflow_quicksort_posts($sortedposts, $startsolved, $index - 1, 'votesdifference');
-                self::moodleoverflow_check_equal_votes($sortedposts, $startsolved, $index - 1);
-            }
         }
 
-        // Now build the group of posts without ratings like helpful/solved.
-        foreach ($answerposts as $post) {
-            if ($post->markedsolution == 0 && $post->markedhelpful == 0) {
-                $sortedposts[$index] = $post;
-                $index++;
-            }
-        }
-        // Update the indices and sort the group by votes.
-        if ($index > $startother) {
-            self::moodleoverflow_quicksort_posts($sortedposts, $startother, $index - 1, 'votesdifference');
-            self::moodleoverflow_check_equal_votes($sortedposts, $startother, $index - 1);
-        }
+        // Step 2: Sort each group after their votes and eventually time modified.
+        self::moodleoverflow_sort_postgroup($solvedhelpfulposts, 0, count($solvedhelpfulposts) - 1);
+        self::moodleoverflow_sort_postgroup($solvedposts, 0, count($solvedposts) - 1);
+        self::moodleoverflow_sort_postgroup($helpfulposts, 0, count($helpfulposts) - 1);
+        self::moodleoverflow_sort_postgroup($unmarkedposts, 0, count($unmarkedposts) - 1);
 
-        // Rearrange the indices and return the sorted posts.
+        // Step 3: Put each group together in the right order depending on the rating preferences.
+        $temp = $solutionspreferred ? array_merge($solvedposts, $helpfulposts) : array_merge($helpfulposts, $solvedposts);
+        $sortedposts = array_merge($sortedposts, $solvedhelpfulposts, $temp, $unmarkedposts);
 
+        // Rearrange the indices and return the sorted posts.
         $neworder = [];
         foreach ($sortedposts as $post) {
             $neworder[$post->id] = $post;
@@ -377,7 +264,7 @@ public static function moodleoverflow_user_rated($postid, $userid = null) {
         // Get the rating.
         $sql = "SELECT firstrated, rating
                   FROM {moodleoverflow_ratings}
-                 WHERE userid = ? AND postid = ? AND (rating = 1 OR rating = 2)";
+                  WHERE userid = ? AND postid = ? AND (rating = 1 OR rating = 2)";
 
         return ($DB->get_record_sql($sql, [ $userid, $postid ]));
     }
@@ -393,9 +280,7 @@ public static function moodleoverflow_get_rating($postid) {
         global $DB;
 
         // Retrieve the full post.
-        if (!$post = $DB->get_record('moodleoverflow_posts', ['id' => $postid])) {
-            throw new moodle_exception('postnotexist', 'moodleoverflow');
-        }
+        $post = moodleoverflow_get_record_or_exception('moodleoverflow_posts', ['id' => $postid], 'postnotexist');
 
         // Get the rating for this single post.
         return self::moodleoverflow_get_ratings_by_discussion($post->discussion, $postid);
@@ -498,57 +383,37 @@ public static function moodleoverflow_get_reputation_instance($moodleoverflowid,
 
         // Initiate a variable.
         $reputation = 0;
-
-        if ($moodleoverflow->anonymous != anonymous::EVERYTHING_ANONYMOUS) {
-
-            // Get all posts of this user in this module.
-            // Do not count votes for own posts.
-            $sql = "SELECT r.id, r.postid as post, r.rating
-                  FROM {moodleoverflow_posts} p
-                  JOIN {moodleoverflow_ratings} r ON p.id = r.postid
-                 WHERE p.userid = ? AND NOT r.userid = ? AND r.moodleoverflowid = ? ";
-
-            if ($moodleoverflow->anonymous == anonymous::QUESTION_ANONYMOUS) {
-                $sql .= " AND p.parent <> 0 ";
-            }
-
-            $sql .= "ORDER BY r.postid ASC";
-
-            $params = [$userid, $userid, $moodleoverflowid];
-            $records = $DB->get_records_sql($sql, $params);
-
-            // Check if there are results.
-            $records = (isset($records)) ? $records : [];
-
-            // Iterate through all ratings.
-            foreach ($records as $record) {
-
-                // The rating is a downvote.
-                if ($record->rating == RATING_DOWNVOTE) {
+        // Get all posts of this user in this module.
+        // Do not count votes for own posts.
+        $sql = "SELECT r.id, r.postid as post, r.rating
+              FROM {moodleoverflow_posts} p
+              JOIN {moodleoverflow_ratings} r ON p.id = r.postid
+              JOIN {moodleoverflow} m ON r.moodleoverflowid = m.id
+             WHERE p.userid = ? AND NOT r.userid = ? AND r.moodleoverflowid = ? AND m.anonymous <> ?";
+
+        if ($moodleoverflow->anonymous == anonymous::QUESTION_ANONYMOUS) {
+            $sql .= " AND p.parent <> 0 ";
+        }
+
+        $sql .= "ORDER BY r.postid ASC";
+
+        $params = [$userid, $userid, $moodleoverflowid, anonymous::EVERYTHING_ANONYMOUS];
+        $records = $DB->get_records_sql($sql, $params);
+        // Iterate through all ratings.
+        foreach ($records as $record) {
+            switch ($record->rating) {
+                case RATING_DOWNVOTE:
                     $reputation += get_config('moodleoverflow', 'votescaledownvote');
-                    continue;
-                }
-
-                // The rating is an upvote.
-                if ($record->rating == RATING_UPVOTE) {
+                    break;
+                case RATING_UPVOTE:
                     $reputation += get_config('moodleoverflow', 'votescaleupvote');
-                    continue;
-                }
-
-                // The post has been marked as helpful by the question owner.
-                if ($record->rating == RATING_HELPFUL) {
+                    break;
+                case RATING_HELPFUL:
                     $reputation += get_config('moodleoverflow', 'votescalehelpful');
-                    continue;
-                }
-
-                // The post has been marked as solved by a teacher.
-                if ($record->rating == RATING_SOLVED) {
+                    break;
+                case RATING_SOLVED:
                     $reputation += get_config('moodleoverflow', 'votescalesolved');
-                    continue;
-                }
-
-                // Another rating should not exist.
-                continue;
+                    break;
             }
         }
 
@@ -556,7 +421,7 @@ public static function moodleoverflow_get_reputation_instance($moodleoverflowid,
         // Votes for own posts are not counting.
         $sql = "SELECT COUNT(id) as amount
                 FROM {moodleoverflow_ratings}
-                WHERE userid = ? AND moodleoverflowid = ? AND (rating = 1 OR rating = 2)";
+                 WHERE userid = ? AND moodleoverflowid = ? AND (rating = 1 OR rating = 2)";
         $params = [$userid, $moodleoverflowid];
         $votes = $DB->get_record_sql($sql, $params);
 
@@ -592,9 +457,7 @@ public static function moodleoverflow_get_reputation_course($courseid, $userid =
         $reputation = 0;
 
         // Check if the course exists.
-        if (!$course = $DB->get_record('course', ['id' => $courseid])) {
-            throw new moodle_exception('invalidcourseid');
-        }
+        $course = moodleoverflow_get_record_or_exception('course', ['id' => $courseid], 'invalidcourseid', '*', true);
 
         // Get all moodleoverflow instances in this course.
         $sql = "SELECT id
@@ -604,9 +467,6 @@ public static function moodleoverflow_get_reputation_course($courseid, $userid =
         $params = [$course->id];
         $instances = $DB->get_records_sql($sql, $params);
 
-        // Check if there are instances in this course.
-        $instances = (isset($instances)) ? $instances : [];
-
         // Sum the reputation of each individual instance.
         foreach ($instances as $instance) {
             $reputation += self::moodleoverflow_get_reputation_instance($instance->id, $userid);
@@ -631,11 +491,11 @@ private static function moodleoverflow_check_old_rating($postid, $userid, $oldra
         // Initiate the array.
         $rating = [];
 
-        // Get the normal rating.
         $sql = "SELECT *
-                FROM {moodleoverflow_ratings}
-                WHERE userid = ? AND postid = ? AND (rating = 1 OR rating = 2)";
-        $rating['normal'] = $DB->get_record_sql($sql, [ $userid, $postid ]);
+                FROM {moodleoverflow_ratings}";
+        // Get the normal rating.
+        $condition = " WHERE userid = ? AND postid = ? AND (rating = 1 OR rating = 2)";
+        $rating['normal'] = $DB->get_record_sql($sql . $condition, [$userid, $postid]);
 
         // Return the rating if it is requested.
         if ($oldrating == RATING_DOWNVOTE || $oldrating == RATING_UPVOTE) {
@@ -643,10 +503,8 @@ private static function moodleoverflow_check_old_rating($postid, $userid, $oldra
         }
 
         // Get the solved rating.
-        $sql = "SELECT *
-                FROM {moodleoverflow_ratings}
-                WHERE postid = ? AND rating = 3";
-        $rating['solved'] = $DB->get_record_sql($sql, [ $postid ]);
+        $condition = " WHERE postid = ? AND rating = 3";
+        $rating['solved'] = $DB->get_record_sql($sql . $condition, [ $postid ]);
 
         // Return the rating if it is requested.
         if ($oldrating == RATING_SOLVED) {
@@ -654,10 +512,8 @@ private static function moodleoverflow_check_old_rating($postid, $userid, $oldra
         }
 
         // Get the helpful rating.
-        $sql = "SELECT *
-                FROM {moodleoverflow_ratings}
-                WHERE postid = ? AND rating = 4";
-        $rating['helpful'] = $DB->get_record_sql($sql, [ $postid ]);
+        $condition = " WHERE postid = ? AND rating = 4";
+        $rating['helpful'] = $DB->get_record_sql($sql . $condition, [ $postid ]);
 
         // Return the rating if it is requested.
         if ($oldrating == RATING_HELPFUL) {
@@ -678,8 +534,6 @@ private static function moodleoverflow_check_old_rating($postid, $userid, $oldra
      * @return bool
      */
     private static function moodleoverflow_can_be_changed($postid, $rating, $userid) {
-        global $CFG;
-
         // Check if the old read record exists.
         $old = self::moodleoverflow_check_old_rating($postid, $userid, $rating);
         if (!$old) {
@@ -691,7 +545,6 @@ private static function moodleoverflow_can_be_changed($postid, $rating, $userid)
 
     /**
      * Removes a rating record.
-     *
      * @param int             $postid
      * @param int             $rating
      * @param int             $userid
@@ -711,11 +564,7 @@ private static function moodleoverflow_remove_rating($postid, $rating, $userid,
         $oldrecord = self::moodleoverflow_check_old_rating($postid, $userid, $rating);
 
         // Trigger an event.
-        $params = [
-            'objectid' => $oldrecord->id,
-            'context' => $modulecontext,
-        ];
-        $event = \mod_moodleoverflow\event\rating_deleted::create($params);
+        $event = \mod_moodleoverflow\event\rating_deleted::create(['objectid' => $oldrecord->id, 'context' => $modulecontext]);
         $event->add_record_snapshot('moodleoverflow_ratings', $oldrecord);
         $event->trigger();
 
@@ -818,65 +667,19 @@ public static function moodleoverflow_user_can_rate($post, $modulecontext, $user
     }
 
     /**
-     * Sorts answerposts of a discussion with quicksort algorithm
-     * @param array  $posts     the posts that are being sorted
-     * @param int    $low       the index from where the sorting begins
-     * @param int    $high      the index until the array is being sorted
-     * @param string $sortby    the attribute by which the posts are being sorted, can be 'votesdifference' or 'modified'
-     */
-    private static function moodleoverflow_quicksort_posts(array &$posts, $low, $high, $sortby): void {
-        if ($low >= $high) {
-            return;
-        }
-        $left = $low;
-        $right = $high;
-        $pivot = 0;
-        if ($sortby == 'votesdifference') {
-            $pivot = $posts[intval(($low + $high) / 2)]->votesdifference;
-        } else if ($sortby == 'modified') {
-            $pivot = $posts[intval(($low + $high) / 2)]->modified;
-        }
-        do {
-            if ($sortby == 'votesdifference') {
-                while ($posts[$left]->votesdifference > $pivot) {
-                    $left++;
-                }
-                while ($posts[$right]->votesdifference < $pivot) {
-                    $right--;
-                }
-            } else if ($sortby == 'modified') {
-                while ($posts[$left]->modified < $pivot) {
-                    $left++;
-                }
-                while ($posts[$right]->modified > $pivot) {
-                    $right--;
-                }
-            }
-            if ($left <= $right) {
-                $temp = $posts[$right];
-                $posts[$right] = $posts[$left];
-                $posts[$left] = $temp;
-                $right--;
-                $left++;
-            }
-        } while ($left <= $right);
-        if ($low < $right) {
-            self::moodleoverflow_quicksort_posts($posts, $low, $right, $sortby);
-        }
-        if ($high > $left ) {
-            self::moodleoverflow_quicksort_posts($posts, $left, $high, $sortby);
-        }
-    }
-
-    /**
-     * Helper function for moodleoverflow_sort_answer_by_rating. For posts that have the same mark and votesdifference,
-     * the posts are sorted by time modified
+     * Helper function for moodleoverflow_sort_answer_by_rating. Sorts a group of posts (solved and helpful, only solved/helpful
+     * and other) after their votesdifference and if needed after their modified time.
+     *
      * @param array $posts  The array that will be sorted
      * @param int   $low    Startindex from where equal votes will be checked
      * @param int   $high   Endindex until where equal votes will be checked
      * @return void
      */
-    private static function moodleoverflow_check_equal_votes(&$posts, $low, $high) {
+    private static function moodleoverflow_sort_postgroup(&$posts, $low, $high) {
+        // First sort the array after their votesdifference.
+        moodleoverflow_quick_array_sort($posts, 0, $high, 'votesdifference', 'desc');
+
+        // Check if posts have the same votesdifference and sort them after their modified time if needed.
         while ($low < $high) {
             if ($posts[$low]->votesdifference == $posts[$low + 1]->votesdifference) {
                 $tempstartindex = $low;
@@ -885,7 +688,7 @@ private static function moodleoverflow_check_equal_votes(&$posts, $low, $high) {
                       ($posts[$tempendindex]->votesdifference == $posts[$tempendindex + 1]->votesdifference)) {
                     $tempendindex++;
                 }
-                self::moodleoverflow_quicksort_posts($posts, $tempstartindex, $tempendindex, 'modified');
+                moodleoverflow_quick_array_sort($posts, $tempstartindex, $tempendindex, 'modified', 'asc');
                 $low = $tempendindex + 1;
             } else {
                 $low++;
diff --git a/classes/readtracking.php b/classes/readtracking.php
index 24d4530498..bc2b556e82 100644
--- a/classes/readtracking.php
+++ b/classes/readtracking.php
@@ -90,13 +90,8 @@ public static function moodleoverflow_is_tracked($moodleoverflow, $user = null)
             $user = $USER;
         }
 
-        // Guests cannot track a moodleoverflow.
-        if (isguestuser($USER) || empty($USER->id)) {
-            return false;
-        }
-
-        // Check if the moodleoverflow can be generally tracked.
-        if (!self::moodleoverflow_can_track_moodleoverflows($moodleoverflow)) {
+        // Guests cannot track a moodleoverflow. The moodleoverflow should be generally trackable.
+        if (isguestuser($USER) || empty($USER->id) || !self::moodleoverflow_can_track_moodleoverflows($moodleoverflow)) {
             return false;
         }
 
@@ -134,14 +129,10 @@ public static function moodleoverflow_mark_moodleoverflow_read($cm, $userid = nu
         $discussions = moodleoverflow_get_discussions_unread($cm);
 
         // Iterate through all of this discussions.
-        foreach ($discussions as $discussionid => $amount) {
-
+        foreach ($discussions as $discussionid) {
             // Mark the discussion as read.
-            if (!self::moodleoverflow_mark_discussion_read($discussionid, context_module::instance($cm->id), $userid)) {
-                throw new moodle_exception('markreadfailed', 'moodleoverflow');
-
-                return false;
-            }
+            $markedcheck = self::moodleoverflow_mark_discussion_read($discussionid, context_module::instance($cm->id), $userid);
+            moodleoverflow_throw_exception_with_check($markedcheck !== true, 'markreadfailed');
         }
 
         return true;
@@ -174,11 +165,8 @@ public static function moodleoverflow_mark_discussion_read($discussionid, $modco
             }
 
             // Mark the post as read.
-            if (!self::moodleoverflow_mark_post_read($userid, $post)) {
-                throw new moodle_exception('markreadfailed', 'moodleoverflow');
-
-                return false;
-            }
+            $postreadcheck = self::moodleoverflow_mark_post_read($userid, $post);
+            moodleoverflow_throw_exception_with_check(!$postreadcheck, 'markreadfailed');
         }
 
         // The discussion has been marked as read.
diff --git a/classes/subscriptions.php b/classes/subscriptions.php
index 83af4181d2..2063c067f1 100644
--- a/classes/subscriptions.php
+++ b/classes/subscriptions.php
@@ -216,7 +216,7 @@ public static function fill_subscription_cache($moodleoverflowid, $userid = null
                 $subscriptions = $DB->get_recordset('moodleoverflow_subscriptions', $params, '', 'id, userid');
 
                 // Loop through the records.
-                foreach ($subscriptions as $id => $data) {
+                foreach ($subscriptions as $data) {
 
                     // Create a new record if necessary.
                     if (!isset(self::$moodleoverflowcache[$data->userid])) {
@@ -985,14 +985,13 @@ public static function moodleoverflow_get_subscribe_link($moodleoverflow, $conte
     /**
      * Given a new post, subscribes the user to the thread the post was posted in.
      *
-     * @param object $fromform       The submitted form
      * @param \stdClass       $moodleoverflow The moodleoverflow record
      * @param \stdClass       $discussion     The discussion record
      * @param \context_module $modulecontext  The context of the module
      *
      * @return bool
      */
-    public static function moodleoverflow_post_subscription($fromform, $moodleoverflow, $discussion, $modulecontext) {
+    public static function moodleoverflow_post_subscription($moodleoverflow, $discussion, $modulecontext) {
         global $USER;
 
         // Check for some basic information.
diff --git a/classes/tables/userstats_table.php b/classes/tables/userstats_table.php
index 677dc7d081..d88fa7ce21 100644
--- a/classes/tables/userstats_table.php
+++ b/classes/tables/userstats_table.php
@@ -26,7 +26,9 @@
 defined('MOODLE_INTERNAL') || die();
 
 use mod_moodleoverflow\ratings;
+global $CFG;
 require_once($CFG->dirroot . '/mod/moodleoverflow/lib.php');
+require_once($CFG->dirroot . '/mod/moodleoverflow/locallib.php');
 require_once($CFG->libdir . '/tablelib.php');
 
 /**
@@ -69,13 +71,8 @@ public function __construct($uniqueid, $courseid, $moodleoverflow, $url) {
 
         $this->set_attribute('class', 'moodleoverflow-statistics-table');
         $this->set_attribute('id', $uniqueid);
-        $this->define_columns(['username',
-                               'receivedupvotes',
-                               'receiveddownvotes',
-                               'forumactivity',
-                               'courseactivity',
-                               'forumreputation',
-                               'coursereputation', ]);
+        $this->define_columns(['username', 'receivedupvotes', 'receiveddownvotes', 'forumactivity', 'courseactivity',
+                               'forumreputation', 'coursereputation', ]);
         $this->define_baseurl($url);
         $this->define_headers([get_string('fullnameuser'),
                                get_string('userstatsupvotes', 'moodleoverflow'),
@@ -102,95 +99,17 @@ public function out() {
         $this->finish_output();
     }
 
-    /**
-     * Method to sort the userstatsdata-table.
-     *
-     * @param array $sortorder The sort order array.
-     *
-     * @return void
-     */
-    private function sort_table_data($sortorder) {
-        $key = $sortorder['sortby'];
-        // The index of each object in usertable is it's value of $key.
-        $length = count($this->userstatsdata);
-        if ($sortorder['sortorder'] == 4) {
-            // 4 means sort in ascending order.
-            $this->quick_usertable_sort(0, $length - 1, $key, 'asc');
-        } else if ($sortorder['sortorder'] == 3) {
-            // 3 means sort in descending order.
-            $this->quick_usertable_sort(0, $length - 1, $key, 'desc');
-        }
-    }
-
-    /**
-     * Sorts userstatsdata with quicksort algorithm.
-     *
-     * @param int    $low       index for quicksort.
-     * @param int    $high      index for quicksort.
-     * @param int    $key       the column that is being sorted (upvotes, downvotes etc.).
-     * @param string $order     sort in ascending or descending order.
-     *
-     * @return void
-     */
-    private function quick_usertable_sort($low, $high, $key, $order) {
-        if ($low >= $high) {
-            return;
-        }
-        $left = $low;
-        $right = $high;
-        $pivot = $this->userstatsdata[intval(($low + $high) / 2)];
-        $pivot = $pivot->$key;
-        do {
-            if ($order == 'asc') {
-                while ($this->userstatsdata[$left]->$key < $pivot) {
-                    $left++;
-                }
-                while ($this->userstatsdata[$right]->$key > $pivot) {
-                    $right--;
-                }
-            } else if ($order == 'desc') {
-                while ($this->userstatsdata[$left]->$key > $pivot) {
-                    $left++;
-                }
-                while ($this->userstatsdata[$right]->$key < $pivot) {
-                    $right--;
-                }
-            }
-            if ($left <= $right) {
-                $temp = $this->userstatsdata[$right];
-                $this->userstatsdata[$right] = $this->userstatsdata[$left];
-                $this->userstatsdata[$left] = $temp;
-                $right--;
-                $left++;
-            }
-        } while ($left <= $right);
-        if ($low < $right) {
-            if ($order == 'asc') {
-                $this->quick_usertable_sort($low, $right, $key, 'asc');
-            } else if ($order == 'desc') {
-                $this->quick_usertable_sort($low, $right, $key, 'desc');
-            }
-        }
-        if ($high > $left) {
-            if ($order == 'asc') {
-                $this->quick_usertable_sort($left, $high, $key, 'asc');
-            } else if ($order == 'desc') {
-                $this->quick_usertable_sort($left, $high, $key, 'desc');
-            }
-        }
-    }
-
     /**
      * Method to collect all the data.
      * Method will collect all users from the given course and will determine the user statistics
-     *
-     * @return 2d-array with user statistic
+     * Builds an 2d-array with user statistic
      */
     public function get_table_data() {
         // Get all userdata from a course.
         $context = \context_course::instance($this->courseid);
         $users = get_enrolled_users($context , '',  0, 'u.id, u.firstname, u.lastname');
 
+        // Step 1.0: Build the datatable with all relevant information.
         $ratingdata = $this->get_rating_data();
 
         // Step 2.0: Now collect the data for every user in the course.
@@ -198,55 +117,26 @@ public function get_table_data() {
             $student = $this->createstudent($user);
 
             foreach ($ratingdata as $row) {
-                // Is the rating from or for the current student?
-                if ($row->postuserid !== $student->id && $row->rateuserid !== $student->id) {
-                    continue;
-                }
-
                 // Did the student receive an up- or downvote?
-                // Only count if the discussion is not anonymous or if the user is not starter of the discussion.
-                if ($row->postuserid == $student->id &&
-                   (($row->anonymoussetting == 0) || ($row->anonymoussetting == 1 && $row->postuserid != $row->discussuserid))) {
-                    if ($row->rating == RATING_UPVOTE) {
-                        $student->receivedupvotes += 1;
-                    } else if ($row->rating == RATING_DOWNVOTE) {
-                        $student->receiveddownvotes += 1;
-                    }
+                if ($row->postuserid == $student->id) {
+                    $this->process_received_votes($student, $row);
                 }
 
                 // Did a student submit a rating?
-                // For solution marks: only count a solution if the discussion is not completely anonymous.
-                // For helpful marks: only count helpful marks if the discussion is not any kind of anonymous.
-                // Up and downvotes are always counted.
-                if ($row->rateuserid == $student->id && !array_key_exists($row->rateid, $student->ratedposts) &&
-                    (($row->rating == RATING_SOLVED && $row->anonymoussetting != 2) ||
-                     ($row->rating == RATING_HELPFUL && $row->anonymoussetting == 0) ||
-                     ($row->rating == RATING_UPVOTE) ||
-                     ($row->rating == RATING_DOWNVOTE))) {
-
-                    if ($row->moodleoverflowid == $this->moodleoverflowid) {
-                        $student->forumactivity += 1;
-                    }
-                    $student->courseactivity += 1;
-                    $student->ratedposts[$row->rateid] = $row->rateid;
+                if ($row->rateuserid == $student->id ) {
+                    $this->process_submitted_ratings($student, $row);
                 }
 
-                // Did the student write a post? Only count a written post if: the post is not in an anonymous discussion;
-                // or the post is in a partial anonymous discussion and the user is not the starter of the discussion.
-                if ($row->postuserid == $student->id && !array_key_exists($row->postid, $student->submittedposts) &&
-                    ($row->anonymoussetting == 0 || ($row->anonymoussetting == 1 && $row->postuserid != $row->discussuserid))) {
-
-                    if ($row->moodleoverflowid == $this->moodleoverflowid) {
-                        $student->forumactivity += 1;
-                    }
-                    $student->courseactivity += 1;
-                    $student->submittedposts[$row->postid] = $row->postid;
+                // Did the student write a post?
+                if ($row->postuserid == $student->id ) {
+                    $this->process_written_posts($student, $row);
                 }
+
             }
             // Get the user reputation from the course.
             $student->forumreputation = ratings::moodleoverflow_get_reputation_instance($this->moodleoverflowid, $student->id);
             $student->coursereputation = ratings::moodleoverflow_get_reputation_course($this->courseid, $student->id);
-            array_push($this->userstatsdata, $student);
+            $this->userstatsdata[] = $student;
         }
     }
 
@@ -268,16 +158,16 @@ public function set_helpactivity() {
                                                       get_string('helpamountofactivity', 'moodleoverflow'));
         $this->helpactivity->class = 'helpactivityclass btn btn-link';
         $this->helpactivity->iconattributes = ['role' => 'button',
-                                                    'data-container' => 'body',
-                                                    'data-toggle' => 'popover',
-                                                    'data-placement' => 'right',
-                                                    'data-action' => 'showhelpicon',
-                                                    'data-html' => 'true',
-                                                    'data-trigger' => 'focus',
-                                                    'tabindex' => '0',
-                                                    'data-content' => '<div class=&quot;no-overflow&quot;><p>' .
-                                                                      get_string('helpamountofactivity', 'moodleoverflow') .
-                                                                      '</p> </div>', ];
+                                               'data-container' => 'body',
+                                               'data-toggle' => 'popover',
+                                               'data-placement' => 'right',
+                                               'data-action' => 'showhelpicon',
+                                               'data-html' => 'true',
+                                               'data-trigger' => 'focus',
+                                               'tabindex' => '0',
+                                               'data-content' => '<div class=&quot;no-overflow&quot;><p>' .
+                                                    get_string('helpamountofactivity', 'moodleoverflow') .
+                                                    '</p> </div>', ];
 
         $this->helpactivity->object = \html_writer::span($this->helpactivity->icon,
                                                          $this->helpactivity->class,
@@ -350,7 +240,7 @@ public function col_coursereputation($row) {
     }
 
     /**
-     * Dependeng on the value display success or warning badge.
+     * Depending on the value display success or warning badge.
      * @param int $number
      * @return string
      */
@@ -363,6 +253,7 @@ private function badge_render($number) {
                 $number . \html_writer::end_span());
         }
     }
+
     /**
      * error handling
      * @param object $colname
@@ -372,6 +263,9 @@ private function badge_render($number) {
     public function other_cols($colname, $attempt) {
         return null;
     }
+
+    // Helper functions.
+
     /**
      * Return a student object.
      * @param \stdClass $user
@@ -383,14 +277,14 @@ private function createstudent($user) {
         $student->name = $user->firstname . ' ' . $user->lastname;
         $linktostudent = new \moodle_url('/user/view.php', ['id' => $student->id, 'course' => $this->courseid]);
         $student->link = \html_writer::link($linktostudent->out(), $student->name);
-        $student->submittedposts = []; // Posts written by the student. Key = postid, Value = postid.
-        $student->ratedposts = [];     // Posts that the student rated. Key = rateid, Value = rateid.
+        $student->submittedposts = [];      // Posts written by the student. Key = postid, Value = postid.
+        $student->ratedposts = [];          // Posts that the student rated. Key = rateid, Value = rateid.
         $student->receivedupvotes = 0;
         $student->receiveddownvotes = 0;
-        $student->forumactivity = 0;             // Number of written posts and submitted ratings in the current moodleoverflow.
-        $student->courseactivity = 0;            // Number of written posts and submitted ratings in the course.
-        $student->forumreputation = 0;           // Reputation in the current moodleoverflow.
-        $student->coursereputation = 0;          // Reputation in the course.
+        $student->forumactivity = 0;        // Number of written posts and submitted ratings in the current moodleoverflow.
+        $student->courseactivity = 0;       // Number of written posts and submitted ratings in the course.
+        $student->forumreputation = 0;      // Reputation in the current moodleoverflow.
+        $student->coursereputation = 0;     // Reputation in the course.
         return $student;
     }
 
@@ -401,7 +295,6 @@ private function createstudent($user) {
      */
     private function get_rating_data() {
         global $DB;
-        // Step 1.0: Build the datatable with all relevant Informations.
         $sqlquery = 'SELECT (ROW_NUMBER() OVER (ORDER BY ratings.id)) AS row_num,
                             discuss.id AS discussid,
                             discuss.userid AS discussuserid,
@@ -420,4 +313,95 @@ private function get_rating_data() {
                       WHERE discuss.course = ' . $this->courseid . ';';
         return $DB->get_records_sql($sqlquery);
     }
+
+    /**
+     * Process the received votes for a student.
+     * @param $student
+     * @param $row
+     * @return void
+     */
+    private function process_received_votes(&$student, $row) {
+        // Only count received votes if the post is not anonymous (no anonymous setting or only questioner anonymous discussion).
+        if ((($row->anonymoussetting == 0) || ($row->anonymoussetting == 1 && $row->postuserid != $row->discussuserid))) {
+            if ($row->rating == RATING_UPVOTE) {
+                $student->receivedupvotes += 1;
+            } else if ($row->rating == RATING_DOWNVOTE) {
+                $student->receiveddownvotes += 1;
+            }
+        }
+    }
+
+    /**
+     * Process the submitted ratings from a student.
+     * @param $student
+     * @param $row
+     * @return void
+     */
+    private function process_submitted_ratings(&$student, $row) {
+        // For solution marks: only count a solution if the discussion is not completely anonymous.
+        // For helpful marks: only count helpful marks if the discussion is not any kind of anonymous.
+        // Up and downvotes are always counted.
+        $solvedcheck = ($row->rating == RATING_SOLVED && $row->anonymoussetting != 2);
+        $helpfulcheck = ($row->rating == RATING_HELPFUL && $row->anonymoussetting == 0);
+        $isvote = ($row->rating == RATING_UPVOTE || $row->rating == RATING_DOWNVOTE);
+
+        if (!array_key_exists($row->rateid, $student->ratedposts)) {
+            if ($solvedcheck || $helpfulcheck || $isvote) {
+                $this->increment_forumactivity($student, $row);
+                $student->courseactivity++;
+                $student->ratedposts[$row->rateid] = $row->rateid;
+            }
+        }
+    }
+
+    /**
+     * Process the written posts from a student for the activity.
+     * @param $student
+     * @param $row
+     * @return void
+     */
+    private function process_written_posts(&$student, $row) {
+        // Only count a written post if: the post is not in an anonymous discussion:
+        // or the post is in a partial anonymous discussion and the user is not the starter of the discussion.
+        if (!array_key_exists($row->postid, $student->submittedposts) &&
+            ($row->anonymoussetting == 0 || ($row->anonymoussetting == 1 && $row->postuserid != $row->discussuserid))) {
+
+            $this->increment_forumactivity($student, $row);
+            $student->courseactivity += 1;
+            $student->submittedposts[$row->postid] = $row->postid;
+        }
+    }
+
+    /**
+     * Increments the forum activity of a student.
+     * @param $row
+     * @param $moodleoverflowid
+     * @param $forumactivity
+     * @return void
+     */
+    private function increment_forumactivity(&$student, $row) {
+        if ($row->moodleoverflowid == $this->moodleoverflowid) {
+            $student->forumactivity++;
+        }
+    }
+
+    // Sort function.
+
+    /**
+     * Method to sort the userstatsdata-table.
+     * @param array $sortorder The sort order array.
+     * @return void
+     */
+    private function sort_table_data($sortorder) {
+        $key = $sortorder['sortby'];
+        // The index of each object in usertable is it's value of $key.
+        $length = count($this->userstatsdata);
+        if ($sortorder['sortorder'] == 4) {
+            // 4 means sort in ascending order.
+            moodleoverflow_quick_array_sort($this->userstatsdata, 0, $length - 1, $key, 'asc');
+        } else if ($sortorder['sortorder'] == 3) {
+            // 3 means sort in descending order.
+            moodleoverflow_quick_array_sort($this->userstatsdata, 0, $length - 1, $key, 'desc');
+        }
+    }
 }
diff --git a/classes/task/send_mails.php b/classes/task/send_mails.php
index 310bbc5f88..7991f55023 100644
--- a/classes/task/send_mails.php
+++ b/classes/task/send_mails.php
@@ -89,13 +89,10 @@ public function send_review_notifications() {
         }
 
         $course = null;
-
         $moodleoverflow = null;
         $usersto = null;
         $cm = null;
-
         $discussion = null;
-
         $success = [];
 
         foreach ($postinfos as $postinfo) {
@@ -135,16 +132,8 @@ public function send_review_notifications() {
                         cron_setup_user($userto, $course);
                     }
 
-                    $maildata = new moodleoverflow_email(
-                        $course,
-                        $cm,
-                        $moodleoverflow,
-                        $discussion,
-                        $post,
-                        $userfrom,
-                        $userto,
-                        false
-                    );
+                    $maildata = new moodleoverflow_email($course, $cm, $moodleoverflow, $discussion,
+                                                         $post, $userfrom, $userto, false);
 
                     $textcontext = $maildata->export_for_template($renderertext, true);
                     $htmlcontext = $maildata->export_for_template($rendererhtml, false);
diff --git a/discussion.php b/discussion.php
index 295220bb08..bb0cfec030 100644
--- a/discussion.php
+++ b/discussion.php
@@ -24,6 +24,7 @@
 
 // Include config and locallib.
 require_once('../../config.php');
+global $CFG, $DB, $PAGE, $USER, $SESSION, $OUTPUT;
 require_once($CFG->dirroot . '/mod/moodleoverflow/locallib.php');
 
 // Declare optional parameters.
@@ -39,19 +40,14 @@
 $PAGE->add_body_class('limitedwidth');
 
 // Check if the discussion is valid.
-if (!$discussion = $DB->get_record('moodleoverflow_discussions', ['id' => $d])) {
-    throw new moodle_exception('invaliddiscussionid', 'moodleoverflow');
-}
+$discussion = moodleoverflow_get_record_or_exception('moodleoverflow_discussions', ['id' => $d], 'invaliddiscussionid');
 
 // Check if the related moodleoverflow instance is valid.
-if (!$moodleoverflow = $DB->get_record('moodleoverflow', ['id' => $discussion->moodleoverflow])) {
-    throw new moodle_exception('invalidmoodleoverflowid', 'moodleoverflow');
-}
+$moodleoverflow = moodleoverflow_get_record_or_exception('moodleoverflow', ['id' => $discussion->moodleoverflow],
+                                                         'invalidmoodleoverflowid');
 
 // Check if the related moodleoverflow instance is valid.
-if (!$course = $DB->get_record('course', ['id' => $discussion->course])) {
-    throw new moodle_exception('invalidcourseid');
-}
+$course = moodleoverflow_get_record_or_exception('course', ['id' => $discussion->course], 'invalidcourseid', '*', true);
 
 // Save the allowmultiplemarks setting.
 $marksetting = $DB->get_record('moodleoverflow', ['id' => $moodleoverflow->id], 'allowmultiplemarks');
@@ -83,7 +79,7 @@
 
     if (in_array($ratingid, [RATING_SOLVED, RATING_REMOVE_SOLVED, RATING_HELPFUL, RATING_REMOVE_HELPFUL])) {
         // Rate the post.
-        if (!\mod_moodleoverflow\ratings::moodleoverflow_add_rating($moodleoverflow, $ratedpost, $ratingid, $cm)) {
+        if (!\mod_moodleoverflow\ratings::moodleoverflow_add_rating($moodleoverflow, $ratedpost, $ratingid, $cm, $USER->id)) {
             throw new moodle_exception('ratingfailed', 'moodleoverflow');
         }
 
diff --git a/externallib.php b/externallib.php
index 6427bbfcbb..8e148d368f 100644
--- a/externallib.php
+++ b/externallib.php
@@ -88,19 +88,15 @@ public static function record_vote($postid, $ratingid) {
         $post = $DB->get_record('moodleoverflow_posts', ['id' => $params['postid']], '*', MUST_EXIST);
 
         // Check if the discussion is valid.
-        if (!$discussion = $DB->get_record('moodleoverflow_discussions', ['id' => $post->discussion])) {
-            throw new moodle_exception('invaliddiscussionid', 'moodleoverflow');
-        }
+        $discussion = moodleoverflow_get_record_or_exception('moodleoverflow_discussions', ['id' => $post->discussion],
+                                                             'invaliddiscussionid');
 
         // Check if the related moodleoverflow instance is valid.
-        if (!$moodleoverflow = $DB->get_record('moodleoverflow', ['id' => $discussion->moodleoverflow])) {
-            throw new moodle_exception('invalidmoodleoverflowid', 'moodleoverflow');
-        }
+        $moodleoverflow = moodleoverflow_get_record_or_exception('moodleoverflow', ['id' => $discussion->moodleoverflow],
+                                                                 'invalidmoodleoverflowid');
 
         // Check if the related moodleoverflow instance is valid.
-        if (!$course = $DB->get_record('course', ['id' => $discussion->course])) {
-            throw new moodle_exception('invalidcourseid');
-        }
+        $course = moodleoverflow_get_record_or_exception('course', ['id' => $discussion->course], 'invalidcourseid', '*', true);
 
         // Get the related coursemodule and its context.
         if (!$cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id, $course->id)) {
@@ -114,7 +110,7 @@ public static function record_vote($postid, $ratingid) {
 
         // Rate the post.
         if (!\mod_moodleoverflow\ratings::moodleoverflow_add_rating($moodleoverflow,
-            $params['postid'], $params['ratingid'], $cm)) {
+            $params['postid'], $params['ratingid'], $cm, $USER->id)) {
             throw new moodle_exception('ratingfailed', 'moodleoverflow');
         }
 
diff --git a/index.php b/index.php
index 979e43a7f1..733a3512c5 100644
--- a/index.php
+++ b/index.php
@@ -21,11 +21,15 @@
  * @copyright 2017 Kennet Winter <k_wint10@uni-muenster.de>
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG, $DB, $PAGE, $USER, $SESSION, $OUTPUT;
 
 // Require needed files.
 use core\context\course;
 
 require_once(dirname(dirname(dirname(__FILE__))) . '/config.php');
+global $CFG, $DB, $PAGE, $USER, $SESSION, $OUTPUT;
 require_once(dirname(__FILE__) . '/locallib.php');
 require_once($CFG->dirroot . '/course/lib.php');
 
@@ -46,9 +50,7 @@
 $PAGE->set_url($url);
 
 // Check if the id is related to a valid course.
-if (!$course = $DB->get_record('course', ['id' => $id])) {
-    throw new moodle_exception('invalidcourseid');
-}
+$course = moodleoverflow_get_record_or_exception('course', ['id' => $id], 'invalidcourseid', '*', true);
 
 // From now on, the user must be enrolled to a course.
 require_course_login($course);
diff --git a/lib.php b/lib.php
index 78dca56503..7d7bf7c73c 100644
--- a/lib.php
+++ b/lib.php
@@ -94,7 +94,6 @@
  * @return mixed true if the feature is supported, null if unknown
  */
 function moodleoverflow_supports($feature) {
-    global $CFG;
 
     if (defined('FEATURE_MOD_PURPOSE')) {
         if ($feature == FEATURE_MOD_PURPOSE) {
@@ -130,7 +129,7 @@ function moodleoverflow_supports($feature) {
  *
  * @return int The id of the newly inserted moodleoverflow record
  */
-function moodleoverflow_add_instance(stdClass $moodleoverflow, mod_moodleoverflow_mod_form $mform = null) {
+function moodleoverflow_add_instance(stdClass $moodleoverflow, ?mod_moodleoverflow_mod_form $mform = null) {
     global $DB;
 
     // Set the current time.
@@ -171,12 +170,12 @@ function moodleoverflow_instance_created($context, $moodleoverflow) {
  * (defined by the form in mod_form.php) this function
  * will update an existing instance with new data.
  *
- * @param stdClass                    $moodleoverflow An object from the form in mod_form.php
- * @param mod_moodleoverflow_mod_form $mform          The form instance itself (if needed)
+ * @param stdClass                         $moodleoverflow An object from the form in mod_form.php
+ * @param mod_moodleoverflow_mod_form|null $mform          The form instance itself (if needed)
  *
  * @return boolean Success/Fail
  */
-function moodleoverflow_update_instance(stdClass $moodleoverflow, mod_moodleoverflow_mod_form $mform = null) {
+function moodleoverflow_update_instance(stdClass $moodleoverflow, ?mod_moodleoverflow_mod_form $mform = null) {
     global $DB;
 
     $moodleoverflow->timemodified = time();
@@ -230,11 +229,11 @@ function moodleoverflow_refresh_events($courseid = 0) {
     global $DB;
 
     if ($courseid == 0) {
-        if (!$moodleoverflows = $DB->get_records('moodleoverflow')) {
+        if (!$DB->get_records('moodleoverflow')) {
             return true;
         }
     } else {
-        if (!$moodleoverflows = $DB->get_records('moodleoverflow', ['course' => $courseid])) {
+        if (!$DB->get_records('moodleoverflow', ['course' => $courseid])) {
             return true;
         }
     }
@@ -465,10 +464,10 @@ function moodleoverflow_pluginfile($course, $cm, $context, $filearea, $args, $fo
  * This function is called when the context for the page is a moodleoverflow module. This is not called by AJAX
  * so it is safe to rely on the $PAGE.
  *
- * @param settings_navigation $settingsnav        complete settings navigation tree
- * @param navigation_node     $moodleoverflownode moodleoverflow administration node
+ * @param settings_navigation      $settingsnav        complete settings navigation tree
+ * @param navigation_node|null     $moodleoverflownode moodleoverflow administration node
  */
-function moodleoverflow_extend_settings_navigation(settings_navigation $settingsnav, navigation_node $moodleoverflownode = null) {
+function moodleoverflow_extend_settings_navigation(settings_navigation $settingsnav, ?navigation_node $moodleoverflownode = null) {
     global $CFG, $DB, $PAGE, $USER;
 
     // Retrieve the current moodle record.
diff --git a/locallib.php b/locallib.php
index 2725b5c398..375da72dfd 100644
--- a/locallib.php
+++ b/locallib.php
@@ -47,8 +47,6 @@
 function moodleoverflow_get_discussions($cm, $page = -1, $perpage = 0) {
     global $DB, $CFG, $USER;
 
-    // TODO Refactor variable naming. $discussion->id is first post and $discussion->discussion is discussion id?
-
     // User must have the permission to view the discussions.
     $modcontext = context_module::instance($cm->id);
     if (!capabilities::has(capabilities::VIEW_DISCUSSION, $modcontext)) {
@@ -775,7 +773,7 @@ function moodleoverflow_user_can_see_discussion($moodleoverflow, $discussion, $c
     }
 
     // Retrieve the coursemodule.
-    if (!$cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id, $moodleoverflow->course)) {
+    if (!get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id, $moodleoverflow->course)) {
         throw new moodle_exception('invalidcoursemodule');
     }
 
@@ -1582,7 +1580,7 @@ function moodleoverflow_print_posts_nested($course, &$cm, $moodleoverflow, $disc
  * @return array
  */
 function get_attachments($post, $cm) {
-    global $CFG, $OUTPUT;
+    global $OUTPUT;
     $attachments = [];
 
     if (empty($post->attachment)) {
@@ -2147,7 +2145,6 @@ function moodleoverflow_update_all_grades_for_cm($moodleoverflowid) {
 
 /**
  * Updates all grades.
- *
  */
 function moodleoverflow_update_all_grades() {
     global $DB;
@@ -2156,3 +2153,130 @@ function moodleoverflow_update_all_grades() {
         moodleoverflow_update_all_grades_for_cm($cmid->id);
     }
 }
+
+
+/**
+ * Function to sort an array with a quicksort algorithm. This function is a recursive function that needs to
+ * be called from outside.
+ *
+ * @param array $array The array to be sorted. It is passed by reference.
+ * @param int $low The lowest index of the array. The first call should set it to 0.
+ * @param int $high The highest index of the array. The first call should set it to the length of the array - 1.
+ *
+ * @param string $key The key/attribute after what the algorithm sorts. The key should be an comparable integer.
+ * @param string $order The order of the sorting. It can be 'asc' or 'desc'.
+ * @return void
+ */
+function moodleoverflow_quick_array_sort(&$array, $low, $high, $key, $order) {
+    if ($low >= $high) {
+        return;
+    }
+    $left = $low;
+    $right = $high;
+    $pivot = $array[intval(($low + $high) / 2)]->$key;
+
+    $compare = function($a, $b) use ($order) {
+        if ($order == 'asc') {
+            return $a < $b;
+        } else {
+            return $a > $b;
+        }
+    };
+
+    do {
+        while ($compare($array[$left]->$key, $pivot)) {
+            $left++;
+        }
+        while ($compare($pivot, $array[$right]->$key)) {
+            $right--;
+        }
+        if ($left <= $right) {
+            $temp = $array[$right];
+            $array[$right] = $array[$left];
+            $array[$left] = $temp;
+            $right--;
+            $left++;
+        }
+    } while ($left <= $right);
+    if ($low < $right) {
+        moodleoverflow_quick_array_sort($array, $low, $right, $key, $order);
+    }
+    if ($high > $left) {
+        moodleoverflow_quick_array_sort($array, $left, $high, $key, $order);
+    }
+}
+
+/**
+ * Function to get a record from the database and throw an exception, if the record is not available. The error string is
+ * retrieved from moodleoverflow but can be retrieved from the core too.
+ * @param string $table                 The table to get the record from
+ * @param array $options                Conditions for the record
+ * @param string $exceptionstring       Name of the moodleoverflow exception that should be thrown in case there is no record.
+ * @param string $fields                Optional fields that are retrieved from the found record.
+ * @param bool $coreexception           Optional param if exception is from the core exceptions.
+ * @return mixed $record                The found record
+ */
+function moodleoverflow_get_record_or_exception($table, $options, $exceptionstring, $fields = '*', $coreexception = false) {
+    global $DB;
+    if (!$record = $DB->get_record($table, $options, $fields)) {
+        if ($coreexception) {
+            throw new moodle_exception($exceptionstring);
+        } else {
+            throw new moodle_exception($exceptionstring, 'moodleoverflow');
+        }
+    }
+    return $record;
+}
+
+/**
+ * Function to retrieve a config and throw an exception, if the config is not found.
+ * @param string $plugin            Plugin that has the configuration
+ * @param string $configname        Name of configuration
+ * @param string $errorcode         Error code/name of the exception
+ * @param string $exceptionmodule   Module that has the exception.
+ * @return mixed $config
+ */
+function moodleoverflow_get_config_or_exception($plugin, $configname, $errorcode, $exceptionmodule) {
+    if (!$config = get_config($plugin, $configname)) {
+        throw new moodle_exception($errorcode, $exceptionmodule);
+    }
+    return $config;
+}
+
+/**
+ * Function that throws an exception if a given check is true.
+ * @param bool $check               The result of a boolean check.
+ * @param string $errorcode         Error code/name of the exception
+ * @param string $coreexception     Optional param if exception is from the core exceptions and not moodleoverflow.
+ * @return void
+ */
+function moodleoverflow_throw_exception_with_check($check, $errorcode, $coreexception = false) {
+    if ($check) {
+        if ($coreexception) {
+            throw new moodle_exception($errorcode);
+        } else {
+            throw new moodle_exception($errorcode, 'moodleoverflow');
+        }
+    }
+}
+
+/**
+ * Function that catches unenrolled users and redirects them to the enrolment page.
+ * @param context $coursecontext     The context of the course.
+ * @param int $courseid             Id of the course that the user needs to enrol.
+ * @param string $returnurl         The url to return to after the user has been enrolled.
+ * @return void
+ */
+function moodleoverflow_catch_unenrolled_user($coursecontext, $courseid, $returnurl) {
+    global $SESSION;
+    if (!isguestuser() && !is_enrolled($coursecontext)) {
+        if (enrol_selfenrol_available($courseid)) {
+            $SESSION->wantsurl = qualified_me();
+            $SESSION->enrolcancel = get_local_referer(false);
+            redirect(new \moodle_url('/enrol/index.php', [
+                'id' => $courseid,
+                'returnurl' => $returnurl,
+            ]), get_string('youneedtoenrol'));
+        }
+    }
+}
diff --git a/markposts.php b/markposts.php
index 9354f62912..77c9362253 100644
--- a/markposts.php
+++ b/markposts.php
@@ -21,6 +21,9 @@
  * @copyright 2017 Kennet Winter <k_wint10@uni-muenster.de>
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG, $DB, $PAGE, $USER, $SESSION, $OUTPUT;
 
 // We do not need the locallib here.
 require_once('../../config.php');
@@ -46,14 +49,10 @@
 $PAGE->set_url($url);
 
 // Retrieve the connected moodleoverflow instance.
-if (!$moodleoverflow = $DB->get_record('moodleoverflow', ['id' => $moodleoverflowid])) {
-    throw new moodle_exception('invalidmoodleoverflowid', 'moodleoverflow');
-}
+$moodleoverflow = moodleoverflow_get_record_or_exception('moodleoverflow', ['id' => $moodleoverflowid], 'invalidmoodleoverflowid');
 
 // Retrieve the connected course.
-if (!$course = $DB->get_record('course', ['id' => $moodleoverflow->course])) {
-    throw new moodle_exception('invalidcourseid');
-}
+$course = moodleoverflow_get_record_or_exception('course', ['id' => $moodleoverflow->course], 'invalidcourseid', '*', true);
 
 // Get the coursemodule.
 if (!$cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id, $course->id)) {
@@ -100,10 +99,7 @@
 
     // Check if the discussion exists.
     $options = ['id' => $discussionid, 'moodleoverflow' => $moodleoverflow->id];
-    $discussion = $DB->get_record('moodleoverflow_discussions', $options);
-    if (!$discussion) {
-        throw new moodle_exception('invaliddiscussionid', 'moodleoverflow');
-    }
+    $discussion = moodleoverflow_get_record_or_exception('moodleoverflow_discussions', $options, 'invaliddiscussionid');
 
     // Mark all the discussions read.
     if (!\mod_moodleoverflow\readtracking::moodleoverflow_mark_discussion_read($discussionid,
@@ -114,7 +110,6 @@
         $status = \core\output\notification::NOTIFY_ERROR;
 
     } else {
-
         // The discussion is successfully marked as read.
         $message = get_string('markmoodleoverflowreadsuccessful', 'moodleoverflow');
         $status = \core\output\notification::NOTIFY_SUCCESS;
diff --git a/post.php b/post.php
index 7ca4085ac4..86bf67b23c 100644
--- a/post.php
+++ b/post.php
@@ -22,8 +22,6 @@
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
-// TODO refactor this. For more readability, and to avoid security issues.
-
 // Include config and locallib.
 use mod_moodleoverflow\anonymous;
 use mod_moodleoverflow\review;
@@ -691,8 +689,7 @@
             $discussion = new \stdClass();
             $discussion->id = $fromform->discussion;
             $discussion->moodleoverflow = $moodleoverflow->id;
-            \mod_moodleoverflow\subscriptions::moodleoverflow_post_subscription($fromform,
-                $moodleoverflow, $discussion, $modulecontext);
+            \mod_moodleoverflow\subscriptions::moodleoverflow_post_subscription($moodleoverflow, $discussion, $modulecontext);
 
             // Print a success-message.
             $message .= '<p>' . get_string("postaddedsuccess", "moodleoverflow") . '</p>';
@@ -767,8 +764,7 @@
             $event->trigger();
             // Subscribe to this thread.
             $discussion->moodleoverflow = $moodleoverflow->id;
-            \mod_moodleoverflow\subscriptions::moodleoverflow_post_subscription($fromform,
-                $moodleoverflow, $discussion, $modulecontext);
+            \mod_moodleoverflow\subscriptions::moodleoverflow_post_subscription($moodleoverflow, $discussion, $modulecontext);
         }
 
         // Redirect back to te discussion.
diff --git a/subscribe.php b/subscribe.php
index 0ea5367b30..0af8f73c2a 100644
--- a/subscribe.php
+++ b/subscribe.php
@@ -29,6 +29,8 @@
 require_once(dirname(dirname(dirname(__FILE__))) . '/config.php');
 require_once(dirname(__FILE__) . '/locallib.php');
 
+global $CFG, $DB, $PAGE, $USER, $SESSION, $OUTPUT;
+
 // Define required and optional params.
 $id = required_param('id', PARAM_INT);             // The moodleoverflow to set subscription on.
 $mode = optional_param('mode', null, PARAM_INT);     // The moodleoverflow's subscription mode.
@@ -50,9 +52,8 @@
 }
 if (!is_null($discussionid)) {
     $url->param('d', $discussionid);
-    if (!$discussion = $DB->get_record('moodleoverflow_discussions', ['id' => $discussionid, 'moodleoverflow' => $id])) {
-        throw new moodle_exception('invaliddiscussionid', 'moodleoverflow');
-    }
+    $discussion = moodleoverflow_get_record_or_exception('moodleoverflow_discussions',
+                                                          ['id' => $discussionid, 'moodleoverflow' => $id], 'invaliddiscussionid');
 }
 
 // Set the pages URL.
diff --git a/tests/behat/installed.feature b/tests/behat/installed.feature
index a6f43414c7..52e9a0c4a1 100644
--- a/tests/behat/installed.feature
+++ b/tests/behat/installed.feature
@@ -1,4 +1,4 @@
-@mod @mod_moodleoverflow
+@mod @mod_moodleoverflow @javascript
 Feature: Installation succeeds
   In order to use this plugin
   As a user
diff --git a/tests/behat/topicmove.feature b/tests/behat/topicmove.feature
index 22ae518301..b0cb7dbffa 100644
--- a/tests/behat/topicmove.feature
+++ b/tests/behat/topicmove.feature
@@ -1,7 +1,6 @@
 @mod @mod_moodleoverflow @javascript
 Feature: Teachers can move a discussion in one moodleoverflow forum to another moodleoverflow.
 
-
   Background:
     Given the following "users" exist:
       | username | firstname | lastname | email |
@@ -20,49 +19,48 @@ Feature: Teachers can move a discussion in one moodleoverflow forum to another m
       | moodleoverflow | everything anonymous      | Test moodleoverflow description  | C1      | 2         | 4        |
     And I log in as "admin"
 
-
   Scenario: Move topic from public forum
     Given I am on "Course 1" course homepage
-      And I add a new discussion to "public moodleoverflow one" moodleoverflow with:
+    And I add a new discussion to "public moodleoverflow one" moodleoverflow with:
       | Subject | Public Message |
       | Message | This is the public message  |
-      And I follow "public moodleoverflow one"
-      And I click on "Move this discussion to another moodleoverflow" "link"
-      Then I should see "public moodleoverflow two"
-      And I should see "question anonymous"
-      And I should see "everything anonymous"
-      And I should not see "Move discussion to public moodleoverflow one"
-      When I click on "Move discussion to public moodleoverflow two" "link"
-      And I am on "Course 1" course homepage
-      And I follow "public moodleoverflow two"
-      Then I should see "Public Message"
+    And I follow "public moodleoverflow one"
+    And I click on "Move this discussion to another moodleoverflow" "link"
+    Then I should see "public moodleoverflow two"
+    And I should see "question anonymous"
+    And I should see "everything anonymous"
+    And I should not see "Move discussion to public moodleoverflow one"
+    When I click on "Move discussion to public moodleoverflow two" "link"
+    And I am on "Course 1" course homepage
+    And I follow "public moodleoverflow two"
+    Then I should see "Public Message"
 
   Scenario: Move topic from question anonymous forum
     Given I am on "Course 1" course homepage
-      And I add a new discussion to "question anonymous" moodleoverflow with:
-        | Subject | Question Message |
-        | Message | This is the question anonymous message |
-      And I follow "question anonymous"
-      And I click on "Move this discussion to another moodleoverflow" "link"
-      And I should not see "Move discussion to public moodleoverflow one"
-      And I should not see "Move discussion to public moodleoverflow two"
-      And I should see "question anonymous"
-      And I should see "everything anonymous"
-      When I click on "Move discussion to everything anonymous" "link"
-      And I am on "Course 1" course homepage
-      And I follow "everything anonymous"
-      Then I should see "Question Message"
+    And I add a new discussion to "question anonymous" moodleoverflow with:
+      | Subject | Question Message |
+      | Message | This is the question anonymous message |
+    And I follow "question anonymous"
+    And I click on "Move this discussion to another moodleoverflow" "link"
+    And I should not see "Move discussion to public moodleoverflow one"
+    And I should not see "Move discussion to public moodleoverflow two"
+    And I should see "question anonymous"
+    And I should see "everything anonymous"
+    When I click on "Move discussion to everything anonymous" "link"
+    And I am on "Course 1" course homepage
+    And I follow "everything anonymous"
+    Then I should see "Question Message"
 
   Scenario: Move topic from question anonymous forum
     Given I am on "Course 1" course homepage
-      And I add a new discussion to "everything anonymous" moodleoverflow with:
-        | Subject | Everything Message |
-        | Message | This is the everything anonymous message |
-      And I follow "everything anonymous"
-      And I click on "Move this discussion to another moodleoverflow" "link"
-      And I should not see "Move discussion to public moodleoverflow one"
-      And I should not see "Move discussion to public moodleoverflow two"
-      And I should not see "Move discussion to question anonymous"
-      And I should not see "Move discussion to everything anonymous"
+    And I add a new discussion to "everything anonymous" moodleoverflow with:
+      | Subject | Everything Message |
+      | Message | This is the everything anonymous message |
+    And I follow "everything anonymous"
+    And I click on "Move this discussion to another moodleoverflow" "link"
+    And I should not see "Move discussion to public moodleoverflow one"
+    And I should not see "Move discussion to public moodleoverflow two"
+    And I should not see "Move discussion to question anonymous"
+    And I should not see "Move discussion to everything anonymous"
 
 
diff --git a/tests/dailymail_test.php b/tests/dailymail_test.php
index e27a2f1b50..c546cea291 100644
--- a/tests/dailymail_test.php
+++ b/tests/dailymail_test.php
@@ -60,7 +60,7 @@ final class dailymail_test extends \advanced_testcase {
     /** @var \stdClass discussion instance */
     private $discussion;
 
-    /** @var  moodleoverflow generator */
+    /** @var \component_generator_base moodleoverflow generator */
     private $generator;
 
     /**
@@ -221,10 +221,6 @@ public function test_content_of_mail_delivery(): void {
         $linktodiscussion = '<a href=3D"https://www.example.com/moodle/mod/moodleoverflow/=discussion.php?d=3D'
                             . $this->discussion[0]->id;
 
-        // Assemble text.
-        $text = 'Course: ' . $linktocourse . ' -> ' . $linktoforum . ', Topic: '
-                . $linktodiscussion . ' has ' . $messagecount . ' unread posts.';
-
         $this->assertStringContainsString($linktocourse, $message);
         $this->assertStringContainsString($linktoforum, $message);
         $this->assertStringContainsString($linktodiscussion, $message);
diff --git a/tests/generator/lib.php b/tests/generator/lib.php
index d7455df414..c27be6dad5 100644
--- a/tests/generator/lib.php
+++ b/tests/generator/lib.php
@@ -64,7 +64,7 @@ public function reset() {
      *
      * @return stdClass
      */
-    public function create_instance($record = null, array $options = null) {
+    public function create_instance($record = null, ?array $options = null) {
 
         // Transform the record.
         $record = (object) (array) $record;
diff --git a/tests/privacy_provider_test.php b/tests/privacy_provider_test.php
index d67dab35fd..a9e7490712 100644
--- a/tests/privacy_provider_test.php
+++ b/tests/privacy_provider_test.php
@@ -28,7 +28,9 @@
 global $CFG;
 
 use core_privacy\local\request\approved_contextlist;
+use core_privacy\local\request\approved_userlist;
 use core_privacy\local\request\userlist;
+use core_privacy\local\request\writer;
 use mod_moodleoverflow\privacy\provider;
 use mod_moodleoverflow\privacy\data_export_helper;
 
@@ -92,7 +94,7 @@ protected function assert_discussion_data($expected, $actual, $userid) {
      *
      * @param   object                             $expected The expected data in the post.
      * @param   object                             $actual   The actual data in the post.
-     * @param   \core_privacy\local\request\writer $writer   The writer used
+     * @param   writer $writer   The writer used
      */
     protected function assert_post_data($expected, $actual, $writer) {
         // The message should have been passed through the rewriter.
@@ -138,7 +140,7 @@ public function test_user_has_never_posted(): void {
 
         // Attempting to export data for this context should return nothing either.
         $this->export_context_data_for_user($user->id, $context, 'mod_moodleoverflow');
-        $writer = \core_privacy\local\request\writer::with_context($context);
+        $writer = writer::with_context($context);
         // The provider should always export data for any context explicitly asked of it, but there should be no
         // metadata, files, or discussions.
         $this->assertEmpty($writer->get_data([get_string('discussions', 'mod_moodleoverflow')]));
@@ -160,7 +162,7 @@ public function test_user_has_never_posted_subscribed_to_forum(): void {
         $context = \context_module::instance($cm->id);
 
         // Subscribe the user to the forum.
-        \mod_moodleoverflow\subscriptions::subscribe_user($user->id, $forum, $context);
+        subscriptions::subscribe_user($user->id, $forum, $context);
 
         // Retrieve all contexts - only this context should be returned.
         $contextlist = $this->get_contexts_for_userid($user->id, 'mod_moodleoverflow');
@@ -168,7 +170,7 @@ public function test_user_has_never_posted_subscribed_to_forum(): void {
         $this->assertEquals($context, $contextlist->current());
         // Export all of the data for the context.
         $this->export_context_data_for_user($user->id, $context, 'mod_moodleoverflow');
-        $writer = \core_privacy\local\request\writer::with_context($context);
+        $writer = writer::with_context($context);
         $this->assertTrue($writer->has_any_data());
         $subcontext = data_export_helper::get_subcontext();
         // There should be one item of metadata.
@@ -196,14 +198,14 @@ public function test_user_has_never_posted_subscribed_to_discussion(): void {
         $cm = get_coursemodule_from_instance('moodleoverflow', $forum->id);
         $context = \context_module::instance($cm->id);
         // Subscribe the user to the discussion.
-        \mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($user->id, $discussion, $context);
+        subscriptions::subscribe_user_to_discussion($user->id, $discussion, $context);
         // Retrieve all contexts - only this context should be returned.
         $contextlist = $this->get_contexts_for_userid($user->id, 'mod_moodleoverflow');
         $this->assertCount(1, $contextlist);
         $this->assertEquals($context, $contextlist->current());
         // Export all of the data for the context.
         $this->export_context_data_for_user($user->id, $context, 'mod_moodleoverflow');
-        $writer = \core_privacy\local\request\writer::with_context($context);
+        $writer = writer::with_context($context);
         $this->assertTrue($writer->has_any_data());
         // There should be nothing in the forum. The user is not subscribed there.
         $forumsubcontext = data_export_helper::get_subcontext();
@@ -234,7 +236,7 @@ public function test_user_has_posted_own_discussion(): void {
         list($user, $otheruser) = $this->create_users($course, 2);
         // Post twice - only the second discussion should be included.
         list($discussion, $post) = $this->generator->post_to_forum($forum, $user);
-        list($otherdiscussion, $otherpost) = $this->generator->post_to_forum($forum, $otheruser);
+        list($otherdiscussion) = $this->generator->post_to_forum($forum, $otheruser);
         $cm = get_coursemodule_from_instance('moodleoverflow', $forum->id);
         $context = \context_module::instance($cm->id);
         // Retrieve all contexts - only this context should be returned.
@@ -244,7 +246,7 @@ public function test_user_has_posted_own_discussion(): void {
         // Export all of the data for the context.
         $this->setUser($user);
         $this->export_context_data_for_user($user->id, $context, 'mod_moodleoverflow');
-        $writer = \core_privacy\local\request\writer::with_context($context);
+        $writer = writer::with_context($context);
         $this->assertTrue($writer->has_any_data());
         // The other discussion should not have been returned as we did not post in it.
         $this->assertEmpty($writer->get_data(data_export_helper::get_subcontext($otherdiscussion)));
@@ -264,7 +266,7 @@ public function test_user_has_posted_reply(): void {
         list($user, $otheruser) = $this->create_users($course, 2);
         // Post twice - only the second discussion should be included.
         list($discussion, $post) = $this->generator->post_to_forum($forum, $otheruser);
-        list($otherdiscussion, $otherpost) = $this->generator->post_to_forum($forum, $otheruser);
+        list($otherdiscussion) = $this->generator->post_to_forum($forum, $otheruser);
         $cm = get_coursemodule_from_instance('moodleoverflow', $forum->id);
         $context = \context_module::instance($cm->id);
         // Post a reply to the other person's post.
@@ -277,7 +279,7 @@ public function test_user_has_posted_reply(): void {
         $this->assertEquals($context, $contextlist->current());
         // Export all of the data for the context.
         $this->export_context_data_for_user($user->id, $context, 'mod_moodleoverflow');
-        $writer = \core_privacy\local\request\writer::with_context($context);
+        $writer = writer::with_context($context);
         $this->assertTrue($writer->has_any_data());
         // Refresh the discussions.
         $discussion = $DB->get_record('moodleoverflow_discussions', ['id' => $discussion->id]);
@@ -289,8 +291,7 @@ public function test_user_has_posted_reply(): void {
         $this->assertNotEmpty($data);
         $this->assert_discussion_data($discussion, $data, $user->id);
         // The reply will be included.
-        $this->assert_post_data($reply,
-            $writer->get_data(data_export_helper::get_subcontext($discussion, $reply)), $writer);
+        $this->assert_post_data($reply, $writer->get_data(data_export_helper::get_subcontext($discussion, $reply)), $writer);
     }
 
     /**
@@ -299,10 +300,7 @@ public function test_user_has_posted_reply(): void {
      */
     public function test_user_has_rated_others(): void {
         $course = $this->getDataGenerator()->create_course();
-        $forum = $this->getDataGenerator()->create_module('moodleoverflow', [
-            'course' => $course->id,
-            'scale' => 100,
-        ]);
+        $forum = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id, 'scale' => 100]);
         list($user, $otheruser) = $this->create_users($course, 2);
         list($discussion, $post) = $this->generator->post_to_forum($forum, $otheruser);
         $cm = get_coursemodule_from_instance('moodleoverflow', $forum->id);
@@ -324,7 +322,7 @@ public function test_user_has_rated_others(): void {
         $this->assertEquals($context, $contextlist->current());
         // Export all of the data for the context.
         $this->export_context_data_for_user($user->id, $context, 'mod_moodleoverflow');
-        $writer = \core_privacy\local\request\writer::with_context($context);
+        $writer = writer::with_context($context);
         $this->assertTrue($writer->has_any_data());
         // The discussion should not have been returned as we did not post in it.
         $this->assertEmpty($writer->get_data(data_export_helper::get_subcontext($discussion)));
@@ -342,11 +340,8 @@ public function test_user_has_rated_others(): void {
      */
     public function test_user_has_been_rated(): void {
         $course = $this->getDataGenerator()->create_course();
-        $forum = $this->getDataGenerator()->create_module('moodleoverflow', [
-            'course' => $course->id,
-            'scale' => 100,
-        ]);
-        list($user, $otheruser, $anotheruser) = $this->create_users($course, 3);
+        $forum = $this->getDataGenerator()->create_module('moodleoverflow', [ 'course' => $course->id, 'scale' => 100]);
+        list($user, $otheruser) = $this->create_users($course, 3);
         list($discussion, $post) = $this->generator->post_to_forum($forum, $user);
         $cm = get_coursemodule_from_instance('moodleoverflow', $forum->id);
         $context = \context_module::instance($cm->id);
@@ -367,7 +362,7 @@ public function test_user_has_been_rated(): void {
         $this->assertEquals($context, $contextlist->current());
         // Export all of the data for the context.
         $this->export_context_data_for_user($user->id, $context, 'mod_moodleoverflow');
-        $writer = \core_privacy\local\request\writer::with_context($context);
+        $writer = writer::with_context($context);
         $this->assertTrue($writer->has_any_data());
         $ratingdata = $writer->get_related_data(data_export_helper::get_subcontext($discussion, $post), 'rating');
 
@@ -384,11 +379,10 @@ public function test_user_tracking_data(): void {
         $cmoff = get_coursemodule_from_instance('moodleoverflow', $forumoff->id);
         $contextoff = \context_module::instance($cmoff->id);
         $forumon = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
-        $cmon = get_coursemodule_from_instance('moodleoverflow', $forumon->id);
         list($user) = $this->create_users($course, 1);
         // Set user tracking data.
-        \mod_moodleoverflow\readtracking::moodleoverflow_stop_tracking($forumoff->id, $user->id);
-        \mod_moodleoverflow\readtracking::moodleoverflow_start_tracking($forumon->id, $user->id);
+        readtracking::moodleoverflow_stop_tracking($forumoff->id, $user->id);
+        readtracking::moodleoverflow_start_tracking($forumon->id, $user->id);
         // Run as the user under test.
         $this->setUser($user);
         // Retrieve all contexts - only the forum tracking reads should be included.
@@ -397,8 +391,7 @@ public function test_user_tracking_data(): void {
         $this->assertEquals($contextoff, $contextlist->current());
         // Check export data for each context.
         $this->export_context_data_for_user($user->id, $contextoff, 'mod_moodleoverflow');
-        $this->assertEquals(0,
-            \core_privacy\local\request\writer::with_context($contextoff)->get_metadata([], 'trackreadpreference'));
+        $this->assertEquals(0, writer::with_context($contextoff)->get_metadata([], 'trackreadpreference'));
     }
 
     /**
@@ -416,9 +409,6 @@ public function test_user_read_posts(): void {
         $forum3 = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
         $cm3 = get_coursemodule_from_instance('moodleoverflow', $forum3->id);
         $context3 = \context_module::instance($cm3->id);
-        $forum4 = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
-        $cm4 = get_coursemodule_from_instance('moodleoverflow', $forum4->id);
-        $context4 = \context_module::instance($cm4->id);
         list($author, $user) = $this->create_users($course, 2);
         list($f1d1, $f1p1) = $this->generator->post_to_forum($forum1, $author);
         $f1p1reply = $this->generator->post_to_discussion($forum1, $f1d1, $author);
@@ -432,101 +422,67 @@ public function test_user_read_posts(): void {
         $f3p1reply = $this->generator->post_to_discussion($forum3, $f3d1, $author);
         $f3d1 = $DB->get_record('moodleoverflow_discussions', ['id' => $f3d1->id]);
         list($f3d2, $f3p2) = $this->generator->post_to_forum($forum3, $author);
-        list($f4d1, $f4p1) = $this->generator->post_to_forum($forum4, $author);
-        $f4p1reply = $this->generator->post_to_discussion($forum4, $f4d1, $author);
-        $f4d1 = $DB->get_record('moodleoverflow_discussions', ['id' => $f4d1->id]);
-        list($f4d2, $f4p2) = $this->generator->post_to_forum($forum4, $author);
+
         // Insert read info.
         // User has read post1, but not the reply or second post in forum1.
-        \mod_moodleoverflow\readtracking::moodleoverflow_add_read_record($user->id, $f1p1->id);
+        readtracking::moodleoverflow_add_read_record($user->id, $f1p1->id);
         // User has read post1 and its reply, but not the second post in forum2.
-        \mod_moodleoverflow\readtracking::moodleoverflow_add_read_record($user->id, $f2p1->id);
-        \mod_moodleoverflow\readtracking::moodleoverflow_add_read_record($user->id, $f2p1reply->id);
+        readtracking::moodleoverflow_add_read_record($user->id, $f2p1->id);
+        readtracking::moodleoverflow_add_read_record($user->id, $f2p1reply->id);
         // User has read post2 in forum3.
-        \mod_moodleoverflow\readtracking::moodleoverflow_add_read_record($user->id, $f3p2->id);
+        readtracking::moodleoverflow_add_read_record($user->id, $f3p2->id);
         // Nothing has been read in forum4.
         // Run as the user under test.
         $this->setUser($user);
         // Retrieve all contexts - should be three - forum4 has no data.
         $contextlist = $this->get_contexts_for_userid($user->id, 'mod_moodleoverflow');
         $this->assertCount(3, $contextlist);
-        $contextids = [
-            $context1->id,
-            $context2->id,
-            $context3->id,
-        ];
+        $contextids = [$context1->id, $context2->id, $context3->id];
         sort($contextids);
         $contextlistids = $contextlist->get_contextids();
         sort($contextlistids);
         $this->assertEquals($contextids, $contextlistids);
         // Forum 1.
         $this->export_context_data_for_user($user->id, $context1, 'mod_moodleoverflow');
-        $writer = \core_privacy\local\request\writer::with_context($context1);
+        $writer = writer::with_context($context1);
         // User has read f1p1.
-        $readdata = $writer->get_metadata(
-            data_export_helper::get_subcontext($f1d1, $f1p1),
-            'postread'
-        );
+        $readdata = $writer->get_metadata(data_export_helper::get_subcontext($f1d1, $f1p1), 'postread');
         $this->assertNotEmpty($readdata);
         $this->assertTrue(isset($readdata->firstread));
         $this->assertTrue(isset($readdata->lastread));
         // User has not f1p1reply.
-        $readdata = $writer->get_metadata(
-            data_export_helper::get_subcontext($f1d1, $f1p1reply),
-            'postread'
-        );
+        $readdata = $writer->get_metadata(data_export_helper::get_subcontext($f1d1, $f1p1reply), 'postread');
         $this->assertEmpty($readdata);
         // User has not f1p2.
-        $readdata = $writer->get_metadata(
-            data_export_helper::get_subcontext($f1d2, $f1p2),
-            'postread'
-        );
+        $readdata = $writer->get_metadata(data_export_helper::get_subcontext($f1d2, $f1p2), 'postread');
         $this->assertEmpty($readdata);
         // Forum 2.
         $this->export_context_data_for_user($user->id, $context2, 'mod_moodleoverflow');
-        $writer = \core_privacy\local\request\writer::with_context($context2);
+        $writer = writer::with_context($context2);
         // User has read f2p1.
-        $readdata = $writer->get_metadata(
-            data_export_helper::get_subcontext($f2d1, $f2p1),
-            'postread'
-        );
+        $readdata = $writer->get_metadata(data_export_helper::get_subcontext($f2d1, $f2p1), 'postread');
         $this->assertNotEmpty($readdata);
         $this->assertTrue(isset($readdata->firstread));
         $this->assertTrue(isset($readdata->lastread));
         // User has read f2p1reply.
-        $readdata = $writer->get_metadata(
-            data_export_helper::get_subcontext($f2d1, $f2p1reply),
-            'postread'
-        );
+        $readdata = $writer->get_metadata(data_export_helper::get_subcontext($f2d1, $f2p1reply), 'postread');
         $this->assertNotEmpty($readdata);
         $this->assertTrue(isset($readdata->firstread));
         $this->assertTrue(isset($readdata->lastread));
         // User has not read f2p2.
-        $readdata = $writer->get_metadata(
-            data_export_helper::get_subcontext($f2d2, $f2p2),
-            'postread'
-        );
+        $readdata = $writer->get_metadata(data_export_helper::get_subcontext($f2d2, $f2p2), 'postread');
         $this->assertEmpty($readdata);
         // Forum 3.
         $this->export_context_data_for_user($user->id, $context3, 'mod_moodleoverflow');
-        $writer = \core_privacy\local\request\writer::with_context($context3);
+        $writer = writer::with_context($context3);
         // User has not read f3p1.
-        $readdata = $writer->get_metadata(
-            data_export_helper::get_subcontext($f3d1, $f3p1),
-            'postread'
-        );
+        $readdata = $writer->get_metadata(data_export_helper::get_subcontext($f3d1, $f3p1), 'postread');
         $this->assertEmpty($readdata);
         // User has not read f3p1reply.
-        $readdata = $writer->get_metadata(
-            data_export_helper::get_subcontext($f3d1, $f3p1reply),
-            'postread'
-        );
+        $readdata = $writer->get_metadata(data_export_helper::get_subcontext($f3d1, $f3p1reply), 'postread');
         $this->assertEmpty($readdata);
         // User has read f3p2.
-        $readdata = $writer->get_metadata(
-            data_export_helper::get_subcontext($f3d2, $f3p2),
-            'postread'
-        );
+        $readdata = $writer->get_metadata(data_export_helper::get_subcontext($f3d2, $f3p2), 'postread');
         $this->assertNotEmpty($readdata);
         $this->assertTrue(isset($readdata->firstread));
         $this->assertTrue(isset($readdata->lastread));
@@ -539,45 +495,34 @@ public function test_post_attachment_inclusion(): void {
         global $DB;
         $fs = get_file_storage();
         $course = $this->getDataGenerator()->create_course();
-        list($author, $otheruser) = $this->create_users($course, 2);
-        $forum = $this->getDataGenerator()->create_module('moodleoverflow', [
-            'course' => $course->id,
-            'scale' => 100,
-        ]);
+        list($author) = $this->create_users($course, 2);
+        $forum = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id, 'scale' => 100]);
         $cm = get_coursemodule_from_instance('moodleoverflow', $forum->id);
         $context = \context_module::instance($cm->id);
         // Create a new discussion + post in the forum.
         list($discussion, $post) = $this->generator->post_to_forum($forum, $author);
         $discussion = $DB->get_record('moodleoverflow_discussions', ['id' => $discussion->id]);
         // Add a number of replies.
+        $this->generator->reply_to_post($post, $author);
         $reply = $this->generator->reply_to_post($post, $author);
-        $reply = $this->generator->reply_to_post($post, $author);
-        $reply = $this->generator->reply_to_post($reply, $author);
-        $posts[$reply->id] = $reply;
+        $this->generator->reply_to_post($reply, $author);
         // Add a fake inline image to the original post.
-        $createdfile = $fs->create_file_from_string([
-            'contextid' => $context->id,
-            'component' => 'mod_moodleoverflow',
-            'filearea' => 'attachment',
-            'itemid' => $post->id,
-            'filepath' => '/',
-            'filename' => 'example.jpg',
-        ],
-            'image contents (not really)');
+        $createdfile = $fs->create_file_from_string(['contextid' => $context->id, 'component' => 'mod_moodleoverflow',
+                               'filearea' => 'attachment', 'itemid' => $post->id, 'filepath' => '/', 'filename' => 'example.jpg', ],
+                     'image contents (not really)');
 
         // Create a second discussion + post in the forum without tags.
-        list($otherdiscussion, $otherpost) = $this->generator->post_to_forum($forum, $author);
-        $otherdiscussion = $DB->get_record('moodleoverflow_discussions', ['id' => $otherdiscussion->id]);
+        list(, $otherpost) = $this->generator->post_to_forum($forum, $author);
         // Add a number of replies.
-        $reply = $this->generator->reply_to_post($otherpost, $author);
-        $reply = $this->generator->reply_to_post($otherpost, $author);
+        $this->generator->reply_to_post($otherpost, $author);
+        $this->generator->reply_to_post($otherpost, $author);
         // Run as the user under test.
         $this->setUser($author);
         // Retrieve all contexts - should be one.
         $contextlist = $this->get_contexts_for_userid($author->id, 'mod_moodleoverflow');
         $this->assertCount(1, $contextlist);
         $this->export_context_data_for_user($author->id, $context, 'mod_moodleoverflow');
-        $writer = \core_privacy\local\request\writer::with_context($context);
+        $writer = writer::with_context($context);
         // The inline file should be on the first forum post.
         $subcontext = data_export_helper::get_subcontext($discussion, $post);
         $foundfiles = $writer->get_files($subcontext);
@@ -587,6 +532,8 @@ public function test_post_attachment_inclusion(): void {
 
     /**
      * Ensure that all user data is deleted from a context.
+     *
+     * @return void
      */
     public function test_all_users_deleted_from_context(): void {
         global $DB;
@@ -596,10 +543,7 @@ public function test_all_users_deleted_from_context(): void {
         $forums = [];
         $contexts = [];
         for ($i = 0; $i < 2; $i++) {
-            $forum = $this->getDataGenerator()->create_module('moodleoverflow', [
-                'course' => $course->id,
-                'scale' => 100,
-            ]);
+            $forum = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id, 'scale' => 100]);
             $cm = get_coursemodule_from_instance('moodleoverflow', $forum->id);
             $context = \context_module::instance($cm->id);
             $forums[$forum->id] = $forum;
@@ -623,14 +567,9 @@ public function test_all_users_deleted_from_context(): void {
                 $reply = $this->generator->reply_to_post($reply, $user);
                 $posts[$reply->id] = $reply;
                 // Add a fake inline image to the original post.
-                $fs->create_file_from_string([
-                    'contextid' => $context->id,
-                    'component' => 'mod_moodleoverflow',
-                    'filearea' => 'attachment',
-                    'itemid' => $post->id,
-                    'filepath' => '/',
-                    'filename' => 'example.jpg',
-                ], 'image contents (not really)');
+                $fs->create_file_from_string(['contextid' => $context->id, 'component' => 'mod_moodleoverflow',
+                                              'filearea' => 'attachment', 'itemid' => $post->id, 'filepath' => '/',
+                                              'filename' => 'example.jpg', ], 'image contents (not really)');
             }
         }
         // Mark all posts as read by user.
@@ -639,13 +578,11 @@ public function test_all_users_deleted_from_context(): void {
         foreach ($posts as $post) {
             $discussion = $discussions[$post->discussion];
             $forum = $forums[$discussion->moodleoverflow];
-            $context = $contexts[$forum->id];
             // Mark the post as being read by user.
-            \mod_moodleoverflow\readtracking::moodleoverflow_add_read_record($user->id, $post->id);
+            readtracking::moodleoverflow_add_read_record($user->id, $post->id);
             // Rate the other users content.
             if ($post->userid != $user->id) {
                 $ratedposts[$post->id] = $post;
-
                 $rating = [];
                 $rating['moodleoverflowid'] = $forum->id;
                 $rating['discussionid'] = $discussion->id;
@@ -714,16 +651,17 @@ public function test_all_users_deleted_from_context(): void {
         }
         // Ratings should not have been deleted.
         foreach ($postsinforum as $post) {
-            if (!isset($ratedposts[$post->id])) {
-                continue;
+            if (isset($ratedposts[$post->id])) {
+                $ratings = $DB->get_records('moodleoverflow_ratings', ['postid' => $post->id]);
+                $this->assertNotEmpty($ratings);
             }
-            $ratings = $DB->get_records('moodleoverflow_ratings', ['postid' => $post->id]);
-            $this->assertNotEmpty($ratings);
         }
     }
 
     /**
      * Ensure that all user data is deleted for a specific context.
+     *
+     * @return void
      */
     public function test_delete_data_for_user(): void {
         global $DB;
@@ -733,10 +671,7 @@ public function test_delete_data_for_user(): void {
         $forums = [];
         $contexts = [];
         for ($i = 0; $i < 2; $i++) {
-            $forum = $this->getDataGenerator()->create_module('moodleoverflow', [
-                'course' => $course->id,
-                'scale' => 100,
-            ]);
+            $forum = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id, 'scale' => 100]);
             $cm = get_coursemodule_from_instance('moodleoverflow', $forum->id);
             $context = \context_module::instance($cm->id);
             $forums[$forum->id] = $forum;
@@ -756,7 +691,6 @@ public function test_delete_data_for_user(): void {
                 $postsbyforum[$user->id][$context->id] = [];
                 // Add a number of replies.
                 $posts[$post->id] = $post;
-                $thisforumposts[$post->id] = $post;
                 $postsbyforum[$user->id][$context->id][$post->id] = $post;
                 $reply = $this->generator->reply_to_post($post, $user);
                 $posts[$reply->id] = $reply;
@@ -783,20 +717,16 @@ public function test_delete_data_for_user(): void {
         foreach ($posts as $post) {
             $discussion = $discussions[$post->discussion];
             $forum = $forums[$discussion->moodleoverflow];
-            $context = $contexts[$forum->id];
             // Mark the post as being read by user1.
-            \mod_moodleoverflow\readtracking::moodleoverflow_add_read_record($user1->id, $post->id);
+            readtracking::moodleoverflow_add_read_record($user1->id, $post->id);
         }
         // Rate and tag all posts.
-        $ratedposts = [];
         foreach ($users as $user) {
             foreach ($posts as $post) {
                 $discussion = $discussions[$post->discussion];
                 $forum = $forums[$discussion->moodleoverflow];
-                $context = $contexts[$forum->id];
                 // Rate the other users content.
                 if ($post->userid != $user->id) {
-                    $ratedposts[$post->id] = $post;
 
                     $rating = [];
                     $rating['moodleoverflowid'] = $forum->id;
@@ -840,9 +770,7 @@ public function test_delete_data_for_user(): void {
         // All posts should remain.
         $this->assertCount(40, $DB->get_records('moodleoverflow_posts'));
         // There should be 4 posts belonging to user1 that were not deleted.
-        $this->assertCount(4, $DB->get_records('moodleoverflow_posts', [
-            'userid' => $user1->id,
-        ]));
+        $this->assertCount(4, $DB->get_records('moodleoverflow_posts', ['userid' => $user1->id]));
         // Four of those posts should have been marked as deleted.
         // That means that the user ID is null and the message is empty.
         $this->assertCount(4, $DB->get_records_select('moodleoverflow_posts', "userid = :userid"
@@ -853,19 +781,13 @@ public function test_delete_data_for_user(): void {
             ]));
 
         // Only user1's posts should have been marked this way.
-        $this->assertCount(4, $DB->get_records('moodleoverflow_posts', [
-            'userid' => 0,
-        ]));
+        $this->assertCount(4, $DB->get_records('moodleoverflow_posts', ['userid' => 0]));
         $this->assertCount(4, $DB->get_records_select('moodleoverflow_posts',
-            $DB->sql_compare_text('message') . " = " . $DB->sql_compare_text(':message'), [
-                'message' => '',
-            ]));
+            $DB->sql_compare_text('message') . " = " . $DB->sql_compare_text(':message'), ['message' => '']));
+
         // Only the posts in the first discussion should have been marked this way.
-        $this->assertCount(4, $DB->get_records_select('moodleoverflow_posts',
-            "userid = :userid AND id {$postinsql}",
-            array_merge($postinparams, [
-                'userid' => 0,
-            ])
+        $this->assertCount(4, $DB->get_records_select('moodleoverflow_posts', "userid = :userid AND id {$postinsql}",
+            array_merge($postinparams, ['userid' => 0])
         ));
 
         // Ratings should have been anonymized.
@@ -925,7 +847,7 @@ protected function create_users($course, $count) {
      *
      * @return array The users created
      */
-    protected function create_and_enrol_users($course, $count) {
+    protected function create_and_enrol_users($course, $count): array {
         $users = [];
         for ($i = 0; $i < $count; $i++) {
             $users[$i] = $this->getDataGenerator()->create_user();
@@ -937,6 +859,8 @@ protected function create_and_enrol_users($course, $count) {
 
     /**
      * Ensure that user data for specific users is deleted from a specified context.
+     *
+     * @return void
      */
     public function test_delete_data_for_users(): void {
         global $DB;
@@ -962,13 +886,12 @@ public function test_delete_data_for_users(): void {
 
         $discussions = [];
         $posts = [];
-        $postsbymoodleoverflow = [];
+        $postsbyforum = [];
         // Foreach of the 5 users and foreach of the two Moodleoverflows a post and discussion is created.
         // Additionally, 3 replies to each discussion are created.
-        // Last but not least the original post gets a fake image and attachement.
-        $counter = 0;
+        // Last but not least the original post gets a fake image and attachment.
         foreach ($users as $user) {
-            $postsbymoodleoverflow[$user->id] = [];
+            $postsbyforum[$user->id] = [];
             foreach ($moodleoverflows as $moodleoverflow) {
                 $context = $contexts[$moodleoverflow->id];
 
@@ -977,24 +900,23 @@ public function test_delete_data_for_users(): void {
                 $discussion = $DB->get_record('moodleoverflow_discussions', ['id' => $discussion->id]);
 
                 $discussions[$discussion->id] = $discussion;
-                $postsbymoodleoverflow[$user->id][$context->id] = [];
+                $postsbyforum[$user->id][$context->id] = [];
 
                 // Add a number of replies.
                 $posts[$post->id] = $post;
-                $thismoodleoverflowposts[$post->id] = $post;
-                $postsbymoodleoverflow[$user->id][$context->id][$post->id] = $post;
+                $postsbyforum[$user->id][$context->id][$post->id] = $post;
 
                 $reply = $this->generator->reply_to_post($post, $user);
                 $posts[$reply->id] = $reply;
-                $postsbymoodleoverflow[$user->id][$context->id][$reply->id] = $reply;
+                $postsbyforum[$user->id][$context->id][$reply->id] = $reply;
 
                 $reply = $this->generator->reply_to_post($post, $user);
                 $posts[$reply->id] = $reply;
-                $postsbymoodleoverflow[$user->id][$context->id][$reply->id] = $reply;
+                $postsbyforum[$user->id][$context->id][$reply->id] = $reply;
 
                 $reply = $this->generator->reply_to_post($reply, $user);
                 $posts[$reply->id] = $reply;
-                $postsbymoodleoverflow[$user->id][$context->id][$reply->id] = $reply;
+                $postsbyforum[$user->id][$context->id][$reply->id] = $reply;
 
                 // Add a fake inline image to the original post.
                 $fs->create_file_from_string([
@@ -1021,11 +943,10 @@ public function test_delete_data_for_users(): void {
         $user1 = reset($users);
         foreach ($posts as $post) {
             // Mark the post as being read by user1.
-            \mod_moodleoverflow\readtracking::moodleoverflow_add_read_record($user1->id, $post->id);
+            readtracking::moodleoverflow_add_read_record($user1->id, $post->id);
         }
 
         // Rate all posts (Every user every post).
-
         foreach ($users as $user) {
             foreach ($posts as $post) {
                 $discussion = $discussions[$post->discussion];
@@ -1033,15 +954,9 @@ public function test_delete_data_for_users(): void {
 
                 if ($post->userid != $user->id) {
                     $time = time();
-                    $rating = (object) [
-                        'userid' => $user->id,
-                        'postid' => $post->id,
-                        'discussionid' => $discussion->id,
-                        'moodleoverflowid' => $moodleoverflow->id,
-                        'rating' => 1,
-                        'firstrated' => $time,
-                        'lastchanged' => $time,
-                    ];
+                    $rating = (object) ['userid' => $user->id, 'postid' => $post->id, 'discussionid' => $discussion->id,
+                                        'moodleoverflowid' => $moodleoverflow->id, 'rating' => 1, 'firstrated' => $time,
+                                        'lastchanged' => $time, ];
                     // Inserts a rating into the table.
                     $DB->insert_record('moodleoverflow_ratings', $rating);
                 }
@@ -1051,7 +966,7 @@ public function test_delete_data_for_users(): void {
         // Delete for one of the moodleoverflows all post for the first user.
         $firstcontext = reset($contexts);
 
-        $approveduserlist = new \core_privacy\local\request\approved_userlist($firstcontext, 'mod_moodleoverflow', [$user1->id]);
+        $approveduserlist = new approved_userlist($firstcontext, 'mod_moodleoverflow', [$user1->id]);
         provider::delete_data_for_users($approveduserlist);
 
         // All posts should remain (5 user * 2 Moodleoverflows * 4 Post per Moodleoverflow).
@@ -1059,9 +974,7 @@ public function test_delete_data_for_users(): void {
 
         // User 1 posted in every Moodleoverflow 4 post (8).
         // Post from the first Moodleoverflow are made anonymous.
-        $this->assertCount(4, $DB->get_records('moodleoverflow_posts', [
-            'userid' => $user1->id,
-        ]));
+        $this->assertCount(4, $DB->get_records('moodleoverflow_posts', ['userid' => $user1->id]));
 
         // All of the post from moodleoverflow 1 should have been filed with empty values.
         // That means the userid equals 0, message equals empty string, and message format equals FORMAT_PLAIN.
@@ -1077,8 +990,7 @@ public function test_delete_data_for_users(): void {
         // Ratings were made anonymous from the affected posts.
         // All ratings from user1 in Moodleoverflow1 should have been deleted so 16 entries should be anonymous.
         // (20 post in Moodleoverflow -4 post belonging to user 1).
-        $this->assertCount(16, $DB->get_records_select('moodleoverflow_ratings', "userid = :userid"
-           , ['userid' => 0 ]));
+        $this->assertCount(16, $DB->get_records_select('moodleoverflow_ratings', "userid = :userid" , ['userid' => 0 ]));
         // All ratings should still exist (2 Moodleoverflows * 5 users * 16 post from other people).
         $this->assertCount(160, $DB->get_records('moodleoverflow_ratings'));
 
@@ -1088,9 +1000,7 @@ public function test_delete_data_for_users(): void {
 
         // User 1 posted in every Moodleoverflow 1 discussion.
         // Discussion from the first Moodleoverflow are made anonymous.
-        $this->assertCount(1, $DB->get_records('moodleoverflow_discussions', [
-            'userid' => $user1->id,
-        ]));
+        $this->assertCount(1, $DB->get_records('moodleoverflow_discussions', ['userid' => $user1->id]));
 
         // All of the discussions from moodleoverflow 1 should have been filed with empty values.
         // That means the userid equals 0, and name equals empty string.
@@ -1104,7 +1014,7 @@ public function test_delete_data_for_users(): void {
         // Get all the post ids where files should be deleted.
         $deletedpostids = [];
         $otherpostids = [];
-        foreach ($postsbymoodleoverflow as $user => $contexts) {
+        foreach ($postsbyforum as $user => $contexts) {
             foreach ($contexts as $thiscontextid => $theseposts) {
                 $thesepostids = array_map(function($post) {
                     return $post->id;
@@ -1134,21 +1044,18 @@ public function test_delete_data_for_users(): void {
      * Ensure that the discussion author is listed as a user in the context.
      */
     public function test_get_users_in_context_post_author(): void {
-        global $DB;
-        $component = 'mod_moodleoverflow';
-
         $course = $this->getDataGenerator()->create_course();
 
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
         $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id);
         $context = \context_module::instance($cm->id);
 
-        list($author, $user) = $this->create_users($course, 2);
+        list($author) = $this->create_users($course, 2);
 
-        list($fd1, $fp1) = $this->generator->post_to_forum($moodleoverflow, $author);
+        $this->generator->post_to_forum($moodleoverflow, $author);
 
-        $userlist = new \core_privacy\local\request\userlist($context, $component);
-        \mod_moodleoverflow\privacy\provider::get_users_in_context($userlist);
+        $userlist = new userlist($context, 'moodleoverflow');
+        provider::get_users_in_context($userlist);
 
         // There should only be one user in the list.
         $this->assertCount(1, $userlist);
@@ -1160,33 +1067,26 @@ public function test_get_users_in_context_post_author(): void {
      */
     public function test_get_users_in_context_post_authors(): void {
         global $DB;
-        $component = 'mod_moodleoverflow';
-
         $course = $this->getDataGenerator()->create_course();
 
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
         $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id);
         $context = \context_module::instance($cm->id);
 
-        list($author, $user, $other) = $this->create_users($course, 3);
+        list($author, $user) = $this->create_users($course, 3);
 
-        list($fd1, $fp1) = $this->generator->post_to_forum($moodleoverflow, $author);
-        $fp1reply = $this->generator->post_to_discussion($moodleoverflow, $fd1, $user);
-        $fd1 = $DB->get_record('moodleoverflow_discussions', ['id' => $fd1->id]);
+        list($fd1) = $this->generator->post_to_forum($moodleoverflow, $author);
+        $this->generator->post_to_discussion($moodleoverflow, $fd1, $user);
+        $DB->get_record('moodleoverflow_discussions', ['id' => $fd1->id]);
 
-        $userlist = new \core_privacy\local\request\userlist($context, $component);
-        \mod_moodleoverflow\privacy\provider::get_users_in_context($userlist);
+        $userlist = new userlist($context, 'mod_moodleoverflow');
+        provider::get_users_in_context($userlist);
 
         // Two users - author and replier.
         $this->assertCount(2, $userlist);
-
         $expected = [$author->id, $user->id];
-        sort($expected);
-
         $actual = $userlist->get_userids();
-        sort($actual);
-
-        $this->assertEquals($expected, $actual);
+        $this->assertEquals(sort($expected), sort($actual));
     }
 
     /**
@@ -1195,226 +1095,157 @@ public function test_get_users_in_context_post_authors(): void {
      */
     public function test_get_users_in_context_post_ratings(): void {
         global $DB;
-        $component = 'mod_moodleoverflow';
-
         $course = $this->getDataGenerator()->create_course();
 
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
         $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id);
         $context = \context_module::instance($cm->id);
-
-        list($author, $user, $other) = $this->create_users($course, 3);
-
+        list($author, $user) = $this->create_users($course, 3);
         list($fd1, $fp1) = $this->generator->post_to_forum($moodleoverflow, $author);
         $time = time();
-        $rating = (object) [
-            'userid' => $user->id,
-            'postid' => $fp1->id,
-            'discussionid' => $fd1->id,
-            'moodleoverflowid' => $moodleoverflow->id,
-            'rating' => 1,
-            'firstrated' => $time,
-            'lastchanged' => $time,
-        ];
+        $rating = (object) ['userid' => $user->id, 'postid' => $fp1->id, 'discussionid' => $fd1->id,
+                            'moodleoverflowid' => $moodleoverflow->id, 'rating' => 1, 'firstrated' => $time,
+                            'lastchanged' => $time, ];
+
         // Inserts a rating into the table.
         $DB->insert_record('moodleoverflow_ratings', $rating);
-        $userlist = new \core_privacy\local\request\userlist($context, $component);
-        \mod_moodleoverflow\privacy\provider::get_users_in_context($userlist);
+        $userlist = new userlist($context, 'mod_moodleoverflow');
+        provider::get_users_in_context($userlist);
 
         // Two users - author and rater.
         $this->assertCount(2, $userlist);
-
         $expected = [$author->id, $user->id];
-        sort($expected);
-
         $actual = $userlist->get_userids();
-        sort($actual);
-        $this->assertEquals($expected, $actual);
+        $this->assertEquals(sort($expected), sort($actual));
     }
 
     /**
      * Ensure that all users with a moodleoverflow subscription preference included as a user in the context.
      */
     public function test_get_users_in_context_with_subscription(): void {
-        global $DB;
-        $component = 'mod_moodleoverflow';
-
         $course = $this->getDataGenerator()->create_course();
-
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
         $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id);
         $context = \context_module::instance($cm->id);
-
-        $othermoodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
-        $othercm = get_coursemodule_from_instance('moodleoverflow', $othermoodleoverflow->id);
-        $othercontext = \context_module::instance($othercm->id);
-
-        list($user, $otheruser) = $this->create_users($course, 2);
+        list($user) = $this->create_users($course, 2);
 
         // Subscribe the user to the moodleoverflow.
-        \mod_moodleoverflow\subscriptions::subscribe_user($user->id, $moodleoverflow, $context);
-
-        $userlist = new \core_privacy\local\request\userlist($context, $component);
-        \mod_moodleoverflow\privacy\provider::get_users_in_context($userlist);
+        subscriptions::subscribe_user($user->id, $moodleoverflow, $context);
+        $userlist = new userlist($context, 'mod_moodleoverflow');
+        provider::get_users_in_context($userlist);
 
         // One user - the one with a digest preference.
         $this->assertCount(1, $userlist);
-
         $expected = [$user->id];
-        sort($expected);
-
         $actual = $userlist->get_userids();
-        sort($actual);
-
-        $this->assertEquals($expected, $actual);
+        $this->assertEquals(sort($expected), sort($actual));
     }
 
     /**
      * Ensure that all users with a per-discussion subscription preference included as a user in the context.
      */
     public function test_get_users_in_context_with_discussion_subscription(): void {
-        $component = 'mod_moodleoverflow';
-
         $course = $this->getDataGenerator()->create_course();
-
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
         $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id);
         $context = \context_module::instance($cm->id);
-
         $othermoodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
-
         list($author, $user, $otheruser) = $this->create_users($course, 3);
 
         // Post in both of the moodleoverflows.
-        list($fd1, $fp1) = $this->generator->post_to_forum($moodleoverflow, $author);
-        list($ofd1, $ofp1) = $this->generator->post_to_forum($othermoodleoverflow, $author);
+        list($fd1) = $this->generator->post_to_forum($moodleoverflow, $author);
+        list($ofd1) = $this->generator->post_to_forum($othermoodleoverflow, $author);
 
         // Subscribe the user to the discussions.
-        \mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($user->id, $fd1, $context);
-        \mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($otheruser->id, $ofd1, $context);
+        subscriptions::subscribe_user_to_discussion($user->id, $fd1, $context);
+        subscriptions::subscribe_user_to_discussion($otheruser->id, $ofd1, $context);
 
-        $userlist = new \core_privacy\local\request\userlist($context, $component);
-        \mod_moodleoverflow\privacy\provider::get_users_in_context($userlist);
+        $userlist = new userlist($context, 'mod_moodleoverflow');
+        provider::get_users_in_context($userlist);
 
         // Two users - the author, and the one who subscribed.
         $this->assertCount(2, $userlist);
-
         $expected = [$author->id, $user->id];
-        sort($expected);
-
         $actual = $userlist->get_userids();
-        sort($actual);
-
-        $this->assertEquals($expected, $actual);
+        $this->assertEquals(sort($expected), sort($actual));
     }
 
     /**
      * Ensure that all users with read tracking are included as a user in the context.
      */
     public function test_get_users_in_context_with_read_post_tracking(): void {
-        $component = 'mod_moodleoverflow';
-
         $course = $this->getDataGenerator()->create_course();
-
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
         $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id);
-        $context = \context_module::instance($cm->id);
 
         $othermoodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
         $othercm = get_coursemodule_from_instance('moodleoverflow', $othermoodleoverflow->id);
-        $othercontext = \context_module::instance($othercm->id);
-
         list($author, $user, $otheruser) = $this->create_users($course, 3);
 
         // Post in both of the moodleoverflows.
-        list($fd1, $fp1) = $this->generator->post_to_forum($moodleoverflow, $author);
-        list($ofd1, $ofp1) = $this->generator->post_to_forum($othermoodleoverflow, $author);
+        list(, $fp1) = $this->generator->post_to_forum($moodleoverflow, $author);
+        list(, $ofp1) = $this->generator->post_to_forum($othermoodleoverflow, $author);
 
         // Add read information for those users.
-        \mod_moodleoverflow\readtracking::moodleoverflow_add_read_record($user->id, $fp1->id);
-        \mod_moodleoverflow\readtracking::moodleoverflow_add_read_record($otheruser->id, $ofp1->id);
+        readtracking::moodleoverflow_add_read_record($user->id, $fp1->id);
+        readtracking::moodleoverflow_add_read_record($otheruser->id, $ofp1->id);
 
-        $userlist = new \core_privacy\local\request\userlist($context, $component);
-        \mod_moodleoverflow\privacy\provider::get_users_in_context($userlist);
+        $userlist = new userlist(\context_module::instance($cm->id), 'mod_moodleoverflow');
+        provider::get_users_in_context($userlist);
 
         // Two user - the author, and the one who has read the post.
         $this->assertCount(2, $userlist);
-
         $expected = [$author->id, $user->id];
-        sort($expected);
-
         $actual = $userlist->get_userids();
-        sort($actual);
-
-        $this->assertEquals($expected, $actual);
+        $this->assertEquals(sort($expected), sort($actual));
 
         // Testing again for the other context.
-        $userlist = new \core_privacy\local\request\userlist($othercontext, $component);
-        \mod_moodleoverflow\privacy\provider::get_users_in_context($userlist);
+        $userlist = new userlist(\context_module::instance($othercm->id), 'mod_moodleoverflow');
+        provider::get_users_in_context($userlist);
 
         // Two user - the author, and the one who has read the post.
         $this->assertCount(2, $userlist);
-
         $expected = [$author->id, $otheruser->id];
-        sort($expected);
-
         $actual = $userlist->get_userids();
-        sort($actual);
-
-        $this->assertEquals($expected, $actual);
+        $this->assertEquals(sort($expected), sort($actual));
     }
 
     /**
      * Ensure that all users with tracking preferences are included as a user in the context.
      */
     public function test_get_users_in_context_with_tracking_preferences(): void {
-        global $DB;
-        $component = 'mod_moodleoverflow';
-
         $course = $this->getDataGenerator()->create_course();
-
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
         $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id);
-        $context = \context_module::instance($cm->id);
 
         $othermoodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id]);
         $othercm = get_coursemodule_from_instance('moodleoverflow', $othermoodleoverflow->id);
         $othercontext = \context_module::instance($othercm->id);
-
-        list($author, $user, $otheruser) = $this->create_users($course, 3);
+        list(, $user, $otheruser) = $this->create_users($course, 3);
 
         // Stop tracking the read posts.
-        \mod_moodleoverflow\readtracking::moodleoverflow_stop_tracking($moodleoverflow->id, $user->id);
-        \mod_moodleoverflow\readtracking::moodleoverflow_stop_tracking($othermoodleoverflow->id, $otheruser->id);
+        readtracking::moodleoverflow_stop_tracking($moodleoverflow->id, $user->id);
+        readtracking::moodleoverflow_stop_tracking($othermoodleoverflow->id, $otheruser->id);
 
-        $userlist = new \core_privacy\local\request\userlist($context, $component);
-        \mod_moodleoverflow\privacy\provider::get_users_in_context($userlist);
+        $userlist = new userlist(\context_module::instance($cm->id), 'mod_moodleoverflow');
+        provider::get_users_in_context($userlist);
 
         // One user - the one who is tracking that moodleoverflow.
         $this->assertCount(1, $userlist);
 
         $expected = [$user->id];
-        sort($expected);
-
         $actual = $userlist->get_userids();
-        sort($actual);
-
-        $this->assertEquals($expected, $actual);
+        $this->assertEquals(sort($expected), sort($actual));
 
         // Testing the other context.
-        $userlist = new \core_privacy\local\request\userlist($othercontext, $component);
-        \mod_moodleoverflow\privacy\provider::get_users_in_context($userlist);
+        $userlist = new userlist($othercontext, 'mod_moodleoverflow');
+        provider::get_users_in_context($userlist);
 
         // One user - the one who is tracking that moodleoverflow.
         $this->assertCount(1, $userlist);
-
         $expected = [$otheruser->id];
-        sort($expected);
-
         $actual = $userlist->get_userids();
-        sort($actual);
-
-        $this->assertEquals($expected, $actual);
+        $this->assertEquals(sort($expected), sort($actual));
     }
 
     /**
@@ -1426,28 +1257,23 @@ public function test_grades(): void {
         global $DB;
 
         $course = self::getDataGenerator()->create_course();
-        $forum = self::getDataGenerator()->create_module('moodleoverflow', [
-                'course' => $course->id,
-                'scale' => 100,
-                'grademaxgrade' => 50,
-                'gradescalefactor' => 2,
-        ]);
+        $forum = self::getDataGenerator()->create_module('moodleoverflow', ['course' => $course->id, 'scale' => 100,
+                            'grademaxgrade' => 50, 'gradescalefactor' => 2, ]);
         $cm = get_coursemodule_from_instance('moodleoverflow', $forum->id);
         $context = \context_module::instance($cm->id);
 
         list($user, $user2) = $this->create_and_enrol_users($course, 2);
         list( , $post) = $this->generator->post_to_forum($forum, $user);
-        \mod_moodleoverflow\ratings::moodleoverflow_add_rating($forum, $post->id, RATING_UPVOTE, $cm, $user2->id);
+        ratings::moodleoverflow_add_rating($forum, $post->id, RATING_UPVOTE, $cm, $user2->id);
         moodleoverflow_update_all_grades_for_cm($forum->id);
-        $grades = grade_get_grades($course->id, 'mod', 'moodleoverflow', $forum->id,
-                [$user->id, $user2->id]);
+        $grades = grade_get_grades($course->id, 'mod', 'moodleoverflow', $forum->id, [$user->id, $user2->id]);
         self::assertEquals("2.50", $grades->items[0]->grades[$user->id]->str_grade);
         self::assertEquals("0.50", $grades->items[0]->grades[$user2->id]->str_grade);
 
         // Test export.
         $this->export_context_data_for_user($user->id, $context, 'mod_moodleoverflow');
-        $writer = \core_privacy\local\request\writer::with_context($context);
-        $metadata = $writer->get_all_metadata([]);
+        $writer = writer::with_context($context);
+        $metadata = $writer->get_all_metadata();
         self::assertArrayHasKey('grade', $metadata);
         self::assertEquals(2.5, $metadata['grade']->value);
 
@@ -1457,16 +1283,13 @@ public function test_grades(): void {
         self::assertContains("$context->id", $contextlist->get_contextids());
         provider::delete_data_for_user($contextlist);
         moodleoverflow_update_all_grades_for_cm($forum->id);
-        $grades = $DB->get_records('moodleoverflow_grades', ['moodleoverflowid' => $forum->id], null,
-                'userid, grade');
+        $grades = $DB->get_records('moodleoverflow_grades', ['moodleoverflowid' => $forum->id], null, 'userid, grade');
         self::assertEquals(2.5, $grades[$user->id]->grade);
         self::assertArrayNotHasKey($user2->id, $grades);
 
         // Test delete context.
         provider::delete_data_for_all_users_in_context($context);
         moodleoverflow_update_all_grades_for_cm($forum->id);
-        $grades = $DB->get_records('moodleoverflow_grades', ['moodleoverflowid' => $forum->id], null,
-                'userid, grade');
-        self::assertEmpty($grades);
+        self::assertEmpty($DB->get_records('moodleoverflow_grades', ['moodleoverflowid' => $forum->id], null, 'userid, grade'));
     }
 }
diff --git a/tests/ratings_test.php b/tests/ratings_test.php
index 396a9e50c5..479b133674 100644
--- a/tests/ratings_test.php
+++ b/tests/ratings_test.php
@@ -23,6 +23,7 @@
  */
 namespace mod_moodleoverflow;
 use mod_moodleoverflow\ratings;
+use stdClass;
 
 defined('MOODLE_INTERNAL') || die();
 
@@ -38,51 +39,28 @@
  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 final class ratings_test extends \advanced_testcase {
-    /** @var \stdClass test course */
-    private $course;
 
-    /** @var \stdClass coursemodule */
-    private $coursemodule;
-
-    /** @var \stdClass test moodleoverflow */
-    private $moodleoverflow;
-
-    /** @var \stdClass test teacher */
-    private $teacher;
-
-    /** @var \stdClass test user */
-    private $user1;
-
-    /** @var \stdClass another test user */
-    private $user2;
-
-    /** @var \stdClass a discussion */
-    private $discussion;
-
-    /** @var \stdClass a post from the teacher*/
+    /** @var stdClass a post from the teacher*/
     private $post;
 
-    /** @var \stdClass answer from user 1 */
+    /** @var stdClass answer from user 1 */
     private $answer1;
 
-    /** @var \stdClass answer from user 1 */
+    /** @var stdClass answer from user 1 */
     private $answer2;
 
-    /** @var \stdClass answer from user 1 */
+    /** @var stdClass answer from user 1 */
     private $answer3;
 
-    /** @var \stdClass answer from user 2 */
+    /** @var stdClass answer from user 2 */
     private $answer4;
 
-    /** @var \stdClass answer from user 2 */
+    /** @var stdClass answer from user 2 */
     private $answer5;
 
-    /** @var \stdClass answer from user 2 */
+    /** @var stdClass answer from user 2 */
     private $answer6;
 
-    /** @var \mod_moodleoverflow_generator $generator */
-    private $generator;
-
     /**
      * Test setUp.
      */
@@ -96,8 +74,8 @@ public function setUp(): void {
      */
     public function tearDown(): void {
         // Clear all caches.
-        \mod_moodleoverflow\subscriptions::reset_moodleoverflow_cache();
-        \mod_moodleoverflow\subscriptions::reset_discussion_cache();
+        subscriptions::reset_moodleoverflow_cache();
+        subscriptions::reset_discussion_cache();
     }
 
     // Begin of test functions.
@@ -182,40 +160,32 @@ public function test_answersorting_twogroups(): void {
         $this->set_ratingpreferences(0);
 
         // Test case 1: helpful and solved post, only solved posts.
-        $group1 = 'sh';
-        $group2 = 's';
-        $this->process_groups($group1, $group2);
+        $this->process_groups('sh', 's');
 
         // Test case 2: helpful and solved post, only helpful posts.
-        $group2 = 'h';
-        $this->process_groups($group1, $group2);
+        $this->process_groups('sh', 'h');
 
         // Test case 3: helpful and solved post, not-marked posts.
-        $group2 = 'o';
-        $this->process_groups($group1, $group2);
+        $this->process_groups('sh', 'o');
 
         // Test case 4: only solved posts and only helpful posts with ratingpreferences = 0.
-        $group1 = 's';
-        $group2 = 'h';
         $this->set_ratingpreferences(0);
         $rightorder = [$this->post, $this->answer6, $this->answer5, $this->answer4, $this->answer2, $this->answer1, $this->answer3];
-        $this->process_groups($group1, $group2, $rightorder);
+        $this->process_groups('s', 'h', $rightorder);
 
         // Test case 5: only solved posts and only helpful posts with ratingpreferences = 1.
         $this->set_ratingpreferences(1);
-        $this->process_groups($group1, $group2);
+        $this->process_groups('s', 'h');
 
         // Test case 6: only solved posts and not-marked posts.
-        $group2 = 'o';
-        $this->create_twogroups($group1, $group2);
+        $this->create_twogroups('s', 'o');
         $posts = [$this->post, $this->answer1, $this->answer2, $this->answer3, $this->answer4, $this->answer5, $this->answer6];
         $rightorder = [$this->post, $this->answer2, $this->answer1, $this->answer3, $this->answer6, $this->answer5, $this->answer4];
         $result = $this->postsorderequal(ratings::moodleoverflow_sort_answers_by_ratings($posts), $rightorder);
         $this->assertEquals(1, $result);
 
         // Test case 6: only helpful posts and not-marked posts.
-        $group1 = 'h';
-        $this->process_groups($group1, $group2);
+        $this->process_groups('h', 'o');
     }
 
     /**
@@ -232,8 +202,7 @@ public function test_answersorting_onegroup(): void {
         $this->set_ratingpreferences(0);
 
         // Test case 1: only solved and helpful posts.
-        $group = 'sh';
-        $this->create_onegroup($group);
+        $this->create_onegroup('sh');
         $posts = [$this->post, $this->answer1, $this->answer2, $this->answer3, $this->answer4, $this->answer5, $this->answer6];
         $rightorder = [$this->post, $this->answer4, $this->answer6, $this->answer3, $this->answer1, $this->answer2, $this->answer5];
         $result = $this->postsorderequal(ratings::moodleoverflow_sort_answers_by_ratings($posts), $rightorder);
@@ -246,8 +215,7 @@ public function test_answersorting_onegroup(): void {
         $this->assertEquals(1, $result);
 
         // Test case 2: only solvedposts.
-        $group = 's';
-        $this->create_onegroup($group);
+        $this->create_onegroup('s');
         $rightorder = [$this->post, $this->answer4, $this->answer6, $this->answer3, $this->answer1, $this->answer2, $this->answer5];
         $result = $this->postsorderequal(ratings::moodleoverflow_sort_answers_by_ratings($posts), $rightorder);
         $this->assertEquals(1, $result);
@@ -259,8 +227,7 @@ public function test_answersorting_onegroup(): void {
         $this->assertEquals(1, $result);
 
         // Test case 3: only helpful posts.
-        $group = 'h';
-        $this->create_onegroup($group);
+        $this->create_onegroup('h');
         $rightorder = [$this->post, $this->answer4, $this->answer6, $this->answer3, $this->answer1, $this->answer2, $this->answer5];
         $result = $this->postsorderequal(ratings::moodleoverflow_sort_answers_by_ratings($posts), $rightorder);
         $this->assertEquals(1, $result);
@@ -272,8 +239,7 @@ public function test_answersorting_onegroup(): void {
         $this->assertEquals(1, $result);
 
         // Test case 4: only not marked posts.
-        $group = 'o';
-        $this->create_onegroup($group);
+        $this->create_onegroup('o');
         $rightorder = [$this->post, $this->answer4, $this->answer6, $this->answer3, $this->answer1, $this->answer2, $this->answer5];
         $result = $this->postsorderequal(ratings::moodleoverflow_sort_answers_by_ratings($posts), $rightorder);
         $this->assertEquals(1, $result);
@@ -296,31 +262,30 @@ public function test_answersorting_onegroup(): void {
     private function helper_course_set_up() {
         global $DB;
         // Create a new course with a moodleoverflow forum.
-        $this->course = $this->getDataGenerator()->create_course();
-        $location = ['course' => $this->course->id];
-        $this->moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', $location);
-        $this->coursemodule = get_coursemodule_from_instance('moodleoverflow', $this->moodleoverflow->id);
+        $course = $this->getDataGenerator()->create_course();
+        $location = ['course' => $course->id];
+        $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', $location);
 
         // Create a teacher.
-        $this->teacher = $this->getDataGenerator()->create_user(['firstname' => 'Tamaro', 'lastname' => 'Walter']);
-        $this->getDataGenerator()->enrol_user($this->teacher->id, $this->course->id, 'student');
+        $teacher = $this->getDataGenerator()->create_user(['firstname' => 'Tamaro', 'lastname' => 'Walter']);
+        $this->getDataGenerator()->enrol_user($teacher->id, $course->id, 'student');
 
         // Create 2 users.
-        $this->user1 = $this->getDataGenerator()->create_user(['firstname' => 'Ava', 'lastname' => 'Davis']);
-        $this->getDataGenerator()->enrol_user($this->user1->id, $this->course->id, 'student');
-        $this->user2 = $this->getDataGenerator()->create_user(['firstname' => 'Ethan', 'lastname' => 'Brown']);
-        $this->getDataGenerator()->enrol_user($this->user2->id, $this->course->id, 'student');
+        $user1 = $this->getDataGenerator()->create_user(['firstname' => 'Ava', 'lastname' => 'Davis']);
+        $this->getDataGenerator()->enrol_user($user1->id, $course->id, 'student');
+        $user2 = $this->getDataGenerator()->create_user(['firstname' => 'Ethan', 'lastname' => 'Brown']);
+        $this->getDataGenerator()->enrol_user($user2->id, $course->id, 'student');
 
         // Create a discussion, a parent post and six answers.
-        $this->generator = $this->getDataGenerator()->get_plugin_generator('mod_moodleoverflow');
-        $this->discussion = $this->generator->post_to_forum($this->moodleoverflow, $this->teacher);
-        $this->post = $DB->get_record('moodleoverflow_posts', ['id' => $this->discussion[0]->firstpost], '*');
-        $this->answer1 = $this->generator->reply_to_post($this->discussion[1], $this->user1, true);
-        $this->answer2 = $this->generator->reply_to_post($this->discussion[1], $this->user1, true);
-        $this->answer3 = $this->generator->reply_to_post($this->discussion[1], $this->user1, true);
-        $this->answer4 = $this->generator->reply_to_post($this->discussion[1], $this->user2, true);
-        $this->answer5 = $this->generator->reply_to_post($this->discussion[1], $this->user2, true);
-        $this->answer6 = $this->generator->reply_to_post($this->discussion[1], $this->user2, true);
+        $generator = $this->getDataGenerator()->get_plugin_generator('mod_moodleoverflow');
+        $discussion = $generator->post_to_forum($moodleoverflow, $teacher);
+        $this->post = $DB->get_record('moodleoverflow_posts', ['id' => $discussion[0]->firstpost], '*');
+        $this->answer1 = $generator->reply_to_post($discussion[1], $user1, true);
+        $this->answer2 = $generator->reply_to_post($discussion[1], $user1, true);
+        $this->answer3 = $generator->reply_to_post($discussion[1], $user1, true);
+        $this->answer4 = $generator->reply_to_post($discussion[1], $user2, true);
+        $this->answer5 = $generator->reply_to_post($discussion[1], $user2, true);
+        $this->answer6 = $generator->reply_to_post($discussion[1], $user2, true);
     }
 
 
@@ -335,7 +300,8 @@ private function postsorderequal($sortedposts, $rightorder) {
         if (count($sortedposts) != count($rightorder)) {
             return 0;
         }
-        for ($i = 0; $i < count($sortedposts); $i++) {
+        $numberofposts = count($sortedposts);
+        for ($i = 0; $i < $numberofposts; $i++) {
             // Get the current elements.
             $sortedpost = current($sortedposts);
             $post = current($rightorder);
@@ -542,10 +508,10 @@ private function create_twogroups($group1, $group2) {
      * Executing the sort function and comparing the sorted post to the expected order.
      * @param String $group1
      * @param string $group2
-     * @param array|null $orderposts
+     * @param array $orderposts
      * @return void
      */
-    private function process_groups(String $group1, string $group2, array $orderposts = null) {
+    private function process_groups(String $group1, string $group2, array $orderposts = []) {
         $this->create_twogroups($group1, $group2);
         $posts = [$this->post, $this->answer1, $this->answer2, $this->answer3, $this->answer4, $this->answer5, $this->answer6];
         $rightorder = [$this->post, $this->answer2, $this->answer1, $this->answer3, $this->answer6, $this->answer5, $this->answer4];
diff --git a/tests/subscriptions_test.php b/tests/subscriptions_test.php
index 7fe9eae71d..26d653b7a9 100644
--- a/tests/subscriptions_test.php
+++ b/tests/subscriptions_test.php
@@ -45,8 +45,8 @@ final class subscriptions_test extends advanced_testcase {
      */
     public function setUp(): void {
         // Clear all caches.
-        \mod_moodleoverflow\subscriptions::reset_moodleoverflow_cache();
-        \mod_moodleoverflow\subscriptions::reset_discussion_cache();
+        subscriptions::reset_moodleoverflow_cache();
+        subscriptions::reset_discussion_cache();
     }
 
     /**
@@ -54,8 +54,8 @@ public function setUp(): void {
      */
     public function tearDown(): void {
         // Clear all caches.
-        \mod_moodleoverflow\subscriptions::reset_moodleoverflow_cache();
-        \mod_moodleoverflow\subscriptions::reset_discussion_cache();
+        subscriptions::reset_moodleoverflow_cache();
+        subscriptions::reset_discussion_cache();
     }
 
     /**
@@ -129,34 +129,34 @@ public function test_subscription_modes(): void {
         $this->setUser($user);
 
         // Test the forced subscription.
-        \mod_moodleoverflow\subscriptions::set_subscription_mode($moodleoverflow->id, MOODLEOVERFLOW_FORCESUBSCRIBE);
+        subscriptions::set_subscription_mode($moodleoverflow->id, MOODLEOVERFLOW_FORCESUBSCRIBE);
         $moodleoverflow = $DB->get_record('moodleoverflow', ['id' => $moodleoverflow->id]);
         $this->assertEquals(MOODLEOVERFLOW_FORCESUBSCRIBE,
-            \mod_moodleoverflow\subscriptions::get_subscription_mode($moodleoverflow));
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_forcesubscribed($moodleoverflow));
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribable($moodleoverflow, $modulecontext));
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::subscription_disabled($moodleoverflow));
+            subscriptions::get_subscription_mode($moodleoverflow));
+        $this->assertTrue(subscriptions::is_forcesubscribed($moodleoverflow));
+        $this->assertFalse(subscriptions::is_subscribable($moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::subscription_disabled($moodleoverflow));
 
         // Test the disallowed subscription.
-        \mod_moodleoverflow\subscriptions::set_subscription_mode($moodleoverflow->id, MOODLEOVERFLOW_DISALLOWSUBSCRIBE);
+        subscriptions::set_subscription_mode($moodleoverflow->id, MOODLEOVERFLOW_DISALLOWSUBSCRIBE);
         $moodleoverflow = $DB->get_record('moodleoverflow', ['id' => $moodleoverflow->id]);
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::subscription_disabled($moodleoverflow));
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribable($moodleoverflow, $modulecontext));
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_forcesubscribed($moodleoverflow));
+        $this->assertTrue(subscriptions::subscription_disabled($moodleoverflow));
+        $this->assertFalse(subscriptions::is_subscribable($moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::is_forcesubscribed($moodleoverflow));
 
         // Test the initial subscription.
-        \mod_moodleoverflow\subscriptions::set_subscription_mode($moodleoverflow->id, MOODLEOVERFLOW_INITIALSUBSCRIBE);
+        subscriptions::set_subscription_mode($moodleoverflow->id, MOODLEOVERFLOW_INITIALSUBSCRIBE);
         $moodleoverflow = $DB->get_record('moodleoverflow', ['id' => $moodleoverflow->id]);
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribable($moodleoverflow, $modulecontext));
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::subscription_disabled($moodleoverflow));
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_forcesubscribed($moodleoverflow));
+        $this->assertTrue(subscriptions::is_subscribable($moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::subscription_disabled($moodleoverflow));
+        $this->assertFalse(subscriptions::is_forcesubscribed($moodleoverflow));
 
         // Test the choose subscription.
-        \mod_moodleoverflow\subscriptions::set_subscription_mode($moodleoverflow->id, MOODLEOVERFLOW_CHOOSESUBSCRIBE);
+        subscriptions::set_subscription_mode($moodleoverflow->id, MOODLEOVERFLOW_CHOOSESUBSCRIBE);
         $moodleoverflow = $DB->get_record('moodleoverflow', ['id' => $moodleoverflow->id]);
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribable($moodleoverflow, $modulecontext));
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::subscription_disabled($moodleoverflow));
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_forcesubscribed($moodleoverflow));
+        $this->assertTrue(subscriptions::is_subscribable($moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::subscription_disabled($moodleoverflow));
+        $this->assertFalse(subscriptions::is_forcesubscribed($moodleoverflow));
     }
 
     /**
@@ -182,7 +182,7 @@ public function test_unsubscribable_moodleoverflows(): void {
         $this->setUser($user);
 
         // Without any subscriptions, there should be nothing returned.
-        $result = \mod_moodleoverflow\subscriptions::get_unsubscribable_moodleoverflows();
+        $result = subscriptions::get_unsubscribable_moodleoverflows();
         $this->assertEquals(0, count($result));
 
         // Create the moodleoverflows.
@@ -196,15 +196,15 @@ public function test_unsubscribable_moodleoverflows(): void {
         $this->getDataGenerator()->create_module('moodleoverflow', $options);
 
         // At present the user is only subscribed to the initial moodleoverflow.
-        $result = \mod_moodleoverflow\subscriptions::get_unsubscribable_moodleoverflows();
+        $result = subscriptions::get_unsubscribable_moodleoverflows();
         $this->assertEquals(1, count($result));
 
         // Ensure that the user is enrolled in all of the moodleoverflows execpt force subscribe.
-        \mod_moodleoverflow\subscriptions::subscribe_user($user->id, $disallow, $modulecontext);
-        \mod_moodleoverflow\subscriptions::subscribe_user($user->id, $choose, $modulecontext);
+        subscriptions::subscribe_user($user->id, $disallow, $modulecontext);
+        subscriptions::subscribe_user($user->id, $choose, $modulecontext);
 
         // At present the user  is subscribed to all three moodleoverflows.
-        $result = \mod_moodleoverflow\subscriptions::get_unsubscribable_moodleoverflows();
+        $result = subscriptions::get_unsubscribable_moodleoverflows();
         $this->assertEquals(3, count($result));
     }
 
@@ -217,16 +217,12 @@ public function test_moodleoverflow_toggle_as_other(): void {
         // Reset the database after testing.
         $this->resetAfterTest(true);
 
-        // Create a course with a moodleoverflow.
+        // Create a course with a moodleoverflow. Get the module context and enroll a user in the course as a student.
         $course = $this->getDataGenerator()->create_course();
         $options = ['course' => $course->id];
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', $options);
-
-        // Get the module context.
         $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id);
         $modulecontext = \context_module::instance($cm->id);
-
-        // Create a user enrolled in the course as a student.
         list ($author) = $this->helper_create_users($course, 1);
 
         // Post a discussion to the moodleoverflow.
@@ -236,149 +232,83 @@ public function test_moodleoverflow_toggle_as_other(): void {
         $discussion->moodleoverflow = $moodleoverflow->id;
 
         // Check that the user is currently not subscribed to the moodleoverflow.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow,
-            $modulecontext));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
 
         // Check that the user is unsubscribed from the discussion too.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow,
-            $modulecontext, $discussion->id));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext, $discussion->id));
+
+        // Declare the options for the subscription tables.
+        $discussoptions = ['userid' => $author->id, 'discussion' => $discussion->id];
+        $subscriptionoptions = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
 
         // Check thast we have no records in either on the subscription tables.
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(0, $count);
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(0, $count);
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
-        // Subscribing to the moodleoverflow should create a record in the subscription table,
-        // but the moodleoverflow discussion subscriptions table.
-        \mod_moodleoverflow\subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(0, $count);
+        // Subscribing to the moodleoverflow should add a record to the moodleoverflow subscription table.
+        subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext);
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
-        // Unsubscribing should remove the record from the moodleoverflow subscription table.
-        // Do not modify the moodleoverflow discussion subscriptions table.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user($author->id, $moodleoverflow, $modulecontext);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(0, $count);
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(0, $count);
+        // Unsubscribing should remove the record from the moodleoverflow subscription table. The discussion table stays the same.
+        subscriptions::unsubscribe_user($author->id, $moodleoverflow, $modulecontext);
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
-        // Enroling the user in the discussion should add one record to the
-        // moodleoverflow discussion table without modifying the form subscription.
-        \mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(0, $count);
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(1, $count);
+        // Subscribing to the discussion should only add a record to the discussion subscription table.
+        subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext);
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
-        // Unsubscribing should remove the record from the moodleoverflow subscriptions
-        // table and not modify the moodleoverflow discussion subscription table.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(0, $count);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(0, $count);
+        // Unsubscribing should remove the record from the moodleoverflow subscriptions and modify the discussion subscriptions.
+        subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
 
         // Resubscribe to the discussion so that we can check the effect of moodleoverflow-level subscriptions.
-        \mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext);
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(1, $count);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(0, $count);
+        subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext);
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
 
-        // Subscribing to the moodleoverflow should have no effect on the moodleoverflow discussion
-        // subscription table if the user did not request the change himself.
-        \mod_moodleoverflow\subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(1, $count);
+        // Subscribing to the moodleoverflow should have no effect on the discussion subscription.
+        subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext);
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
-        // Unsubbing from the moodleoverflow should have no effect on the moodleoverflow
-        // discussion subscription table if the user did not request the change themself.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user($author->id, $moodleoverflow, $modulecontext);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(0, $count);
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(1, $count);
+        // Unsubbing from the moodleoverflow should have no effect on the discussion subscription.
+        subscriptions::unsubscribe_user($author->id, $moodleoverflow, $modulecontext);
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
-        // Subscribing to the moodleoverflow should remove the per-discussion
-        // subscription preference if the user requested the change themself.
-        \mod_moodleoverflow\subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext, true);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(0, $count);
+        // Subscribing to the moodleoverflow should remove the per-discussion subscription preference if the user wanted the change.
+        subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext, true);
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
         // Now unsubscribe from the current discussion whilst being subscribed to the moodleoverflow as a whole.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(1, $count);
+        subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
-        // Unsubscribing from the moodleoverflow should remove the per-discussion
-        // subscription preference if the user requested the change himself.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user($author->id, $moodleoverflow, $modulecontext, true);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(0, $count);
-        $count = $DB->count_records('moodleoverflow_discuss_subs', [
-            'userid' => $author->id,
-            'discussion' => $discussion->id,
-        ]);
-        $this->assertEquals(0, $count);
+        // Unsubscribing from the moodleoverflow should remove per-discussion subscription preference if the user wanted the change.
+        subscriptions::unsubscribe_user($author->id, $moodleoverflow, $modulecontext, true);
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
         // Subscribe to the discussion.
-        \mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(0, $count);
-        $count = $DB->count_records('moodleoverflow_discuss_subs', [
-            'userid' => $author->id,
-            'discussion' => $discussion->id,
-        ]);
-        $this->assertEquals(1, $count);
+        subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext);
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
         // Subscribe to the moodleoverflow without removing the discussion preferences.
-        \mod_moodleoverflow\subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(1, $count);
+        subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext);
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
         // Unsubscribe from the discussion should result in a change.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(1, $count);
+        subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
     }
 
     /**
@@ -397,14 +327,14 @@ public function test_moodleoverflow_discussion_subscription_moodleoverflow_unsub
         list($author) = $this->helper_create_users($course, 1);
 
         // Check that the user is currently not subscribed to the moodleoverflow.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $moodleoverflow));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $moodleoverflow));
 
         // Post a discussion to the moodleoverflow.
         list($discussion, $post) = $this->helper_post_to_moodleoverflow($moodleoverflow, $author);
         unset($post);
 
         // Check that the user is unsubscribed from the discussion too.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow,
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow,
             $moodleoverflow, $discussion));
     }
 
@@ -429,21 +359,21 @@ public function test_moodleoverflow_discussion_subscription_moodleoverflow_subsc
 
         // Enrol the user in the moodleoverflow.
         // If a subscription was added, we get the record ID.
-        $this->assertIsInt(\mod_moodleoverflow\subscriptions::subscribe_user($author->id,
+        $this->assertIsInt(subscriptions::subscribe_user($author->id,
             $moodleoverflow, $modulecontext));
 
         // If we already have a subscription when subscribing the user, we get a boolean (true).
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext));
+        $this->assertTrue(subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext));
 
         // Check that the user is currently subscribed to the moodleoverflow.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
 
         // Post a discussion to the moodleoverflow.
         list($discussion, $post) = $this->helper_post_to_moodleoverflow($moodleoverflow, $author);
         unset($post);
 
         // Check that the user is subscribed to the discussion too.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
             $discussion));
     }
 
@@ -467,7 +397,7 @@ public function test_moodleoverflow_discussion_subscription_moodleoverflow_unsub
         list($author) = $this->helper_create_users($course, 1);
 
         // Check that the user is currently not subscribed to the moodleoverflow.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $moodleoverflow));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $moodleoverflow));
 
         // Post a discussion to the moodleoverflow.
         $discussion = new \stdClass();
@@ -476,18 +406,18 @@ public function test_moodleoverflow_discussion_subscription_moodleoverflow_unsub
         $discussion->moodleoverflow = $moodleoverflow->id;
 
         // Attempting to unsubscribe from the discussion should not make a change.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($author->id,
+        $this->assertFalse(subscriptions::unsubscribe_user_from_discussion($author->id,
             $discussion, $modulecontext));
 
         // Then subscribe them to the discussion.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($author->id,
+        $this->assertTrue(subscriptions::subscribe_user_to_discussion($author->id,
             $discussion, $modulecontext));
 
         // Check that the user is still unsubscribed from the moodleoverflow.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $moodleoverflow));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $moodleoverflow));
 
         // But subscribed to the discussion.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
             $discussion->id));
     }
 
@@ -511,10 +441,10 @@ public function test_moodleoverflow_discussion_subscription_moodleoverflow_subsc
         list($author) = $this->helper_create_users($course, 2);
 
         // Enrol the student in the moodleoverflow.
-        \mod_moodleoverflow\subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext);
+        subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext);
 
         // Check that the user is currently subscribed to the moodleoverflow.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
 
         // Post a discussion to the moodleoverflow.
         $discussion = new \stdClass();
@@ -523,13 +453,13 @@ public function test_moodleoverflow_discussion_subscription_moodleoverflow_subsc
         $discussion->moodleoverflow = $moodleoverflow->id;
 
         // Then unsubscribe them from the discussion.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
+        subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
 
         // Check that the user is still subscribed to the moodleoverflow.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
 
         // But unsubscribed from the discussion.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
             $discussion->id));
     }
 
@@ -538,23 +468,17 @@ public function test_moodleoverflow_discussion_subscription_moodleoverflow_subsc
      */
     public function test_moodleoverflow_discussion_toggle_moodleoverflow_subscribed(): void {
         global $DB;
-
         // Reset the database after testing.
-        $this->resetAfterTest(true);
+        $this->resetAfterTest();
 
-        // Create a course with a moodleoverflow.
+        // Create a course with a moodleoverflow and enroll two users in the course as students and in the moodleoverflow.
         $course = $this->getDataGenerator()->create_course();
         $options = ['course' => $course->id, 'forcesubscribe' => MOODLEOVERFLOW_CHOOSESUBSCRIBE];
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', $options);
-
         $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id);
         $modulecontext = \context_module::instance($cm->id);
-
-        // Create two users enrolled in the course as students.
         list($author) = $this->helper_create_users($course, 2);
-
-        // Enrol the student in the moodleoverflow.
-        \mod_moodleoverflow\subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext);
+        subscriptions::subscribe_user($author->id, $moodleoverflow, $modulecontext);
 
         // Post a discussion to the moodleoverflow.
         $discussion = new \stdClass();
@@ -562,152 +486,82 @@ public function test_moodleoverflow_discussion_toggle_moodleoverflow_subscribed(
         unset($post);
         $discussion->moodleoverflow = $moodleoverflow->id;
 
-        // Check that the user is currently subscribed to the moodleoverflow.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
-
-        // Check that the user is initially subscribed to that discussion.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
-            $discussion->id));
+        // Check that the user is currently subscribed to the moodleoverflow and initially subscribed to that discussion.
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext, $discussion->id));
 
         // An attempt to subscribe again should result in a falsey return to indicate that no change was made.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($author->id,
-            $discussion, $modulecontext));
+        $this->assertFalse(subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext));
 
-        // And there should be no discussion subscriptions (and one moodleoverflow subscription).
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(0, $count);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
+        // Declare the options for the subscription tables.
+        $discussoptions = ['userid' => $author->id, 'discussion' => $discussion->id];
+        $subscriptionoptions = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
 
-        // Then unsubscribe them from the discussion.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
-
-        // Check that the user is still subscribed to the moodleoverflow.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        // And there should be no discussion subscriptions (and one moodleoverflow subscription).
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
 
-        // An attempt to unsubscribe again should result in a falsey return to indicate that no change was made.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($author->id,
-            $discussion, $modulecontext));
+        // Unsubscribe them from the discussion while still subscribe the moodleoverflow. Attempt to unsubscribe again should fail.
+        subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext));
 
         // And there should be a discussion subscriptions (and one moodleoverflow subscription).
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(1, $count);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
-
-        // But unsubscribed from the discussion.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
-            $discussion->id));
-
-        // There should be a record in the discussion subscription tracking table.
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(1, $count);
-
-        // And one in the moodleoverflow subscription tracking table.
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
-
-        // Now subscribe the user again to the discussion.
-        \mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext);
-
-        // Check that the user is still subscribed to the moodleoverflow.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
-
-        // And is subscribed to the discussion again.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
-            $discussion->id));
-
-        // And one in the moodleoverflow subscription tracking table.
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
-
-        // There should be no record in the discussion subscription tracking table.
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(0, $count);
-
-        // And unsubscribe again.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
-
-        // Check that the user is still subscribed to the moodleoverflow.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
 
         // But unsubscribed from the discussion.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
-            $discussion->id));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext, $discussion->id));
 
-        // And one in the moodleoverflow subscription tracking table.
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
+        // There should be one record in the discussion and moodleoverflow subscription tracking table.
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
 
-        // There should be a record in the discussion subscription tracking table.
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(1, $count);
+        // Now subscribe the user again to the discussion. Now discussion and moodleoverflow should be subscribed.
+        subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext);
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext, $discussion->id));
 
-        // And subscribe the user again to the discussion.
-        \mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext);
+        // And one in the moodleoverflow subscription and no record in the discussion tracking table.
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
-        // Check that the user is still subscribed to the moodleoverflow.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        // And unsubscribe again. Only moodleoverflow should be subscribed. Discussion should be unsubscribed.
+        subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext, $discussion->id));
 
-        // And is subscribed to the discussion again.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
-            $discussion->id));
-
-        // There should be no record in the discussion subscription tracking table.
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(0, $count);
+        // There should be one record in the moodleoverflow and discussion subscription tracking table.
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
-        // And one in the forum subscription tracking table.
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
+        // And subscribe the user again to the discussion. Both should be subscribed.
+        subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext);
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext, $discussion->id));
 
-        // And unsubscribe again.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
+        // There should be no record in the discussion and one in the moodleoverflow subscription tracking table.
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
 
-        // But unsubscribed from the discussion.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
-            $discussion->id));
+        // And unsubscribe again from the discussion. Only moodleoverflow should be subscribed.
+        subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext, $discussion->id));
 
-        // Check that the user is still subscribed to the moodleoverflow.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
-
-        // There should be a record in the discussion subscription tracking table.
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(1, $count);
-
-        // And one in the moodleoverflow subscription tracking table.
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(1, $count);
+        // There should be a record in the discussion and one in the moodleoverflow subscription tracking table.
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
 
         // Now unsubscribe the user from the moodleoverflow.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::unsubscribe_user($author->id, $moodleoverflow, $modulecontext,
-            true));
+        $this->assertTrue(subscriptions::unsubscribe_user($author->id, $moodleoverflow, $modulecontext, true));
 
         // This removes both the moodleoverflow, and the moodleoverflow records.
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(0, $count);
-        $options = ['userid' => $author->id, 'moodleoverflow' => $moodleoverflow->id];
-        $count = $DB->count_records('moodleoverflow_subscriptions', $options);
-        $this->assertEquals(0, $count);
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
 
         // And should have reset the discussion cache value.
-        $result = \mod_moodleoverflow\subscriptions::fetch_discussion_subscription($moodleoverflow->id, $author->id);
+        $result = subscriptions::fetch_discussion_subscription($moodleoverflow->id, $author->id);
         $this->assertIsArray($result);
         $this->assertFalse(isset($result[$discussion->id]));
     }
@@ -721,20 +575,16 @@ public function test_moodleoverflow_discussion_toggle_moodleoverflow_unsubscribe
         // Reset the database after testing.
         $this->resetAfterTest(true);
 
-        // Create a course, with a moodleoverflow.
+        // Create a course, with a moodleoverflow and get the module context. Create two users enrolled inthe course as students.
         $course = $this->getDataGenerator()->create_course();
         $options = ['course' => $course->id, 'forcesubscribe' => MOODLEOVERFLOW_CHOOSESUBSCRIBE];
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', $options);
-
-        // Get the module context.
         $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id);
         $modulecontext = \context_module::instance($cm->id);
-
-        // Create two users enrolled in the course as students.
         list($author) = $this->helper_create_users($course, 2);
 
         // Check that the user is currently unsubscribed to the moodleoverflow.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
 
         // Post a discussion to the moodleoverflow.
         $discussion = new \stdClass();
@@ -742,54 +592,47 @@ public function test_moodleoverflow_discussion_toggle_moodleoverflow_unsubscribe
         unset($post);
         $discussion->moodleoverflow = $moodleoverflow->id;
 
+        // Declare the options for the subscription tables.
+        $discussoptions = ['userid' => $author->id, 'discussion' => $discussion->id];
+
         // Check that the user is initially unsubscribed to that discussion.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
-            $discussion->id));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext, $discussion->id));
 
         // Then subscribe them to the discussion.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($author->id,
-            $discussion, $modulecontext));
+        $this->assertTrue(subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext));
 
         // An attempt to subscribe again should result in a falsey return to indicate that no change was made.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($author->id,
-            $discussion, $modulecontext));
+        $this->assertFalse(subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext));
 
         // Check that the user is still unsubscribed from the moodleoverflow.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
 
         // But subscribed to the discussion.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
-            $discussion->id));
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext, $discussion->id));
 
         // There should be a record in the discussion subscription tracking table.
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(1, $count);
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
         // Now unsubscribe the user again from the discussion.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
+        subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
 
         // Check that the user is still unsubscribed from the moodleoverflow.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
 
         // And is unsubscribed from the discussion again.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
-            $discussion->id));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext, $discussion->id));
 
         // There should be no record in the discussion subscription tracking table.
-        $options = ['userid' => $author->id, 'discussion' => $discussion->id];
-        $count = $DB->count_records('moodleoverflow_discuss_subs', $options);
-        $this->assertEquals(0, $count);
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
         // And subscribe the user again to the discussion.
-        \mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext);
+        subscriptions::subscribe_user_to_discussion($author->id, $discussion, $modulecontext);
 
         // And is subscribed to the discussion again.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
-            $discussion->id));
+        $this->assertTrue(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext, $discussion->id));
 
         // Check that the user is still unsubscribed from the moodleoverflow.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
 
         // There should be a record in the discussion subscription tracking table.
         $options = ['userid' => $author->id, 'discussion' => $discussion->id];
@@ -797,14 +640,13 @@ public function test_moodleoverflow_discussion_toggle_moodleoverflow_unsubscribe
         $this->assertEquals(1, $count);
 
         // And unsubscribe again.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
+        subscriptions::unsubscribe_user_from_discussion($author->id, $discussion, $modulecontext);
 
         // But unsubscribed from the discussion.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext,
-            $discussion->id));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext, $discussion->id));
 
         // Check that the user is still unsubscribed from the moodleoverflow.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::is_subscribed($author->id, $moodleoverflow, $modulecontext));
 
         // There should be no record in the discussion subscription tracking table.
         $options = ['userid' => $author->id, 'discussion' => $discussion->id];
@@ -822,37 +664,34 @@ public function test_fetch_subscribed_users_subscriptions(): void {
         // Reset the database after testing.
         $this->resetAfterTest(true);
 
-        // Create a course, with a moodleoverflow. where users are initially subscribed.
+        // Create a course, with a moodleoverflow. where users are initially subscribed and get the module context.
         $course = $this->getDataGenerator()->create_course();
         $options = ['course' => $course->id, 'forcesubscribe' => MOODLEOVERFLOW_INITIALSUBSCRIBE];
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', $options);
-
-        // Get the module context.
         $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id);
         $modulecontext = \context_module::instance($cm->id);
 
-        // Create some user enrolled in the course as a student.
+        // Create five user enrolled in the course as a student.
         $usercount = 5;
         $users = $this->helper_create_users($course, $usercount);
 
         // All users should be subscribed.
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
         $this->assertEquals($usercount, count($subscribers));
 
         // Subscribe the guest user too to the moodleoverflow - they should never be returned by this function.
         $this->getDataGenerator()->enrol_user($CFG->siteguest, $course->id);
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
         $this->assertEquals($usercount, count($subscribers));
 
         // Unsubscribe 2 users.
-        $unsubscribedcount = 2;
-        for ($i = 0; $i < $unsubscribedcount; $i++) {
-            \mod_moodleoverflow\subscriptions::unsubscribe_user($users[$i]->id, $moodleoverflow, $modulecontext);
+        for ($i = 0; $i < 2; $i++) {
+            subscriptions::unsubscribe_user($users[$i]->id, $moodleoverflow, $modulecontext);
         }
 
         // The subscription count should now take into account those users who have been unsubscribed.
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
-        $this->assertEquals($usercount - $unsubscribedcount, count($subscribers));
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
+        $this->assertEquals($usercount - 2, count($subscribers));
     }
 
     /**
@@ -877,7 +716,7 @@ public function test_fetch_subscribed_users_forced(): void {
         $this->helper_create_users($course, $usercount);
 
         // All users should be subscribed.
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
         $this->assertEquals($usercount, count($subscribers));
     }
 
@@ -910,21 +749,19 @@ public function test_fetch_subscribed_users_discussion_subscriptions(): void {
         $discussion->moodleoverflow = $moodleoverflow->id;
 
         // All users should be subscribed.
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
         $this->assertEquals($usercount, count($subscribers));
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext, null,
-            true);
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext, null, true);
         $this->assertEquals($usercount, count($subscribers));
 
-        \mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($users[0]->id, $discussion, $modulecontext);
+        subscriptions::unsubscribe_user_from_discussion($users[0]->id, $discussion, $modulecontext);
 
         // All users should be subscribed.
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
         $this->assertEquals($usercount, count($subscribers));
 
         // All users should be subscribed.
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext, null,
-            true);
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext, null, true);
         $this->assertEquals($usercount, count($subscribers));
 
         // Manually insert an extra subscription for one of the users.
@@ -936,35 +773,27 @@ public function test_fetch_subscribed_users_discussion_subscriptions(): void {
         $DB->insert_record('moodleoverflow_discuss_subs', $record);
 
         // The discussion count should not have changed.
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
         $this->assertEquals($usercount, count($subscribers));
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext, null,
-            true);
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext, null, true);
         $this->assertEquals($usercount, count($subscribers));
 
         // Unsubscribe 2 users.
-        $unsubscribedcount = 2;
-        for ($i = 0; $i < $unsubscribedcount; $i++) {
-            \mod_moodleoverflow\subscriptions::unsubscribe_user($users[$i]->id, $moodleoverflow, $modulecontext);
-        }
+        subscriptions::unsubscribe_user($users[0]->id, $moodleoverflow, $modulecontext);
+        subscriptions::unsubscribe_user($users[1]->id, $moodleoverflow, $modulecontext);
 
         // The subscription count should now take into account those users who have been unsubscribed.
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
-        $this->assertEquals($usercount - $unsubscribedcount, count($subscribers));
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext, null,
-            true);
-        $this->assertEquals($usercount - $unsubscribedcount, count($subscribers));
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
+        $this->assertEquals($usercount - 2, count($subscribers));
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext, null, true);
+        $this->assertEquals($usercount - 2, count($subscribers));
 
         // Now subscribe one of those users back to the discussion.
-        $subedusers = 1;
-        for ($i = 0; $i < $subedusers; $i++) {
-            \mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($users[$i]->id, $discussion, $modulecontext);
-        }
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
-        $this->assertEquals($usercount - $unsubscribedcount, count($subscribers));
-        $subscribers = \mod_moodleoverflow\subscriptions::get_subscribed_users($moodleoverflow, $modulecontext, null,
-            true);
-        $this->assertEquals($usercount - $unsubscribedcount + $subedusers, count($subscribers));
+        subscriptions::subscribe_user_to_discussion($users[0]->id, $discussion, $modulecontext);
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext);
+        $this->assertEquals($usercount - 2, count($subscribers));
+        $subscribers = subscriptions::get_subscribed_users($moodleoverflow, $modulecontext, null, true);
+        $this->assertEquals($usercount - 1, count($subscribers));
     }
 
     /**
@@ -972,7 +801,6 @@ public function test_fetch_subscribed_users_discussion_subscriptions(): void {
      */
     public function test_force_subscribed_to_moodleoverflow(): void {
         global $DB;
-
         // Reset database after testing.
         $this->resetAfterTest(true);
 
@@ -992,7 +820,7 @@ public function test_force_subscribed_to_moodleoverflow(): void {
         $this->getDataGenerator()->enrol_user($user->id, $course->id, $roleids['student']);
 
         // Check that the user is currently subscribed to the moodleoverflow.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::is_subscribed($user->id, $moodleoverflow, $context));
+        $this->assertTrue(subscriptions::is_subscribed($user->id, $moodleoverflow, $context));
 
         assign_capability('mod/moodleoverflow:allowforcesubscribe', CAP_PROHIBIT, $roleids['student'],
             $context);
@@ -1018,17 +846,17 @@ public function test_subscription_cache_prefill(): void {
         $users = $this->helper_create_users($course, 20);
 
         // Reset the subscription cache.
-        \mod_moodleoverflow\subscriptions::reset_moodleoverflow_cache();
+        subscriptions::reset_moodleoverflow_cache();
 
         // Filling the subscription cache should only use a single query, except for Postgres, which delegates actual reading
         // to Cursors, thus tripling the amount of queries. We intend to test the cache, though, so no worries.
-        $this->assertNull(\mod_moodleoverflow\subscriptions::fill_subscription_cache($moodleoverflow->id));
+        $this->assertNull(subscriptions::fill_subscription_cache($moodleoverflow->id));
         $postfillcount = $DB->perf_get_reads();
 
         // Now fetch some subscriptions from that moodleoverflow - these should use
         // the cache and not perform additional queries.
         foreach ($users as $user) {
-            $this->assertTrue(\mod_moodleoverflow\subscriptions::fetch_subscription_cache($moodleoverflow->id, $user->id));
+            $this->assertTrue(subscriptions::fetch_subscription_cache($moodleoverflow->id, $user->id));
         }
         $finalcount = $DB->perf_get_reads();
         $this->assertEquals($finalcount, $postfillcount);
@@ -1053,14 +881,14 @@ public function test_subscription_cache_fill(): void {
         $users = $this->helper_create_users($course, 20);
 
         // Reset the subscription cache.
-        \mod_moodleoverflow\subscriptions::reset_moodleoverflow_cache();
+        subscriptions::reset_moodleoverflow_cache();
 
         // Filling the subscription cache should only use a single query.
         $startcount = $DB->perf_get_reads();
 
         // Fetch some subscriptions from that moodleoverflow - these should not use the cache and will perform additional queries.
         foreach ($users as $user) {
-            $this->assertTrue(\mod_moodleoverflow\subscriptions::fetch_subscription_cache($moodleoverflow->id, $user->id));
+            $this->assertTrue(subscriptions::fetch_subscription_cache($moodleoverflow->id, $user->id));
         }
         $finalcount = $DB->perf_get_reads();
         $this->assertEquals(20, $finalcount - $startcount);
@@ -1080,34 +908,35 @@ public function test_discussion_subscription_cache_fill_for_course(): void {
 
         // Create the moodleoverflows.
         $options = ['course' => $course->id, 'forcesubscribe' => MOODLEOVERFLOW_DISALLOWSUBSCRIBE];
-        $disallowmoodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', $options);
+        $disallowobject = $this->getDataGenerator()->create_module('moodleoverflow', $options);
         $options = ['course' => $course->id, 'forcesubscribe' => MOODLEOVERFLOW_CHOOSESUBSCRIBE];
-        $choosemoodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', $options);
+        $chooseobject = $this->getDataGenerator()->create_module('moodleoverflow', $options);
         $options = ['course' => $course->id, 'forcesubscribe' => MOODLEOVERFLOW_INITIALSUBSCRIBE];
-        $initialmoodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', $options);
+        $initialobject = $this->getDataGenerator()->create_module('moodleoverflow', $options);
 
         // Create some users and keep a reference to the first user.
         $users = $this->helper_create_users($course, 20);
         $user = reset($users);
 
         // Reset the subscription caches.
-        \mod_moodleoverflow\subscriptions::reset_moodleoverflow_cache();
+        subscriptions::reset_moodleoverflow_cache();
 
-        $result = \mod_moodleoverflow\subscriptions::fill_subscription_cache_for_course($course->id, $user->id);
+        $result = subscriptions::fill_subscription_cache_for_course($course->id, $user->id);
         $this->assertNull($result);
         $postfillcount = $DB->perf_get_reads();
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::fetch_subscription_cache($disallowmoodleoverflow->id, $user->id));
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::fetch_subscription_cache($choosemoodleoverflow->id, $user->id));
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::fetch_subscription_cache($initialmoodleoverflow->id, $user->id));
+        $this->assertFalse(subscriptions::fetch_subscription_cache($disallowobject->id, $user->id));
+        $this->assertFalse(subscriptions::fetch_subscription_cache($chooseobject->id, $user->id));
+        $this->assertTrue(subscriptions::fetch_subscription_cache($initialobject->id, $user->id));
         $finalcount = $DB->perf_get_reads();
         $this->assertEquals(0, $finalcount - $postfillcount);
 
         // Test for all users.
         foreach ($users as $user) {
-            $result = \mod_moodleoverflow\subscriptions::fill_subscription_cache_for_course($course->id, $user->id);
-            $this->assertFalse(\mod_moodleoverflow\subscriptions::fetch_subscription_cache($disallowmoodleoverflow->id, $user->id));
-            $this->assertFalse(\mod_moodleoverflow\subscriptions::fetch_subscription_cache($choosemoodleoverflow->id, $user->id));
-            $this->assertTrue(\mod_moodleoverflow\subscriptions::fetch_subscription_cache($initialmoodleoverflow->id, $user->id));
+            $result = subscriptions::fill_subscription_cache_for_course($course->id, $user->id);
+            $this->assertNull($result);
+            $this->assertFalse(subscriptions::fetch_subscription_cache($disallowobject->id, $user->id));
+            $this->assertFalse(subscriptions::fetch_subscription_cache($chooseobject->id, $user->id));
+            $this->assertTrue(subscriptions::fetch_subscription_cache($initialobject->id, $user->id));
         }
         $finalcount = $DB->perf_get_reads();
         $reads = $finalcount - $postfillcount;
@@ -1162,24 +991,24 @@ public function test_discussion_subscription_cache_prefill(): void {
                 if ($usercount % 2) {
                     continue;
                 }
-                \mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($user->id, $discussion, $modulecontext);
+                subscriptions::unsubscribe_user_from_discussion($user->id, $data, $modulecontext);
                 $usercount++;
             }
             $moodleoverflowcount++;
         }
 
         // Reset the subscription caches.
-        \mod_moodleoverflow\subscriptions::reset_moodleoverflow_cache();
-        \mod_moodleoverflow\subscriptions::reset_discussion_cache();
+        subscriptions::reset_moodleoverflow_cache();
+        subscriptions::reset_discussion_cache();
 
         // Filling the discussion subscription cache should only use a single query.
-        $this->assertNull(\mod_moodleoverflow\subscriptions::fill_discussion_subscription_cache($moodleoverflow->id));
+        $this->assertNull(subscriptions::fill_discussion_subscription_cache($moodleoverflow->id));
         $postfillcount = $DB->perf_get_reads();
 
         // Now fetch some subscriptions from that moodleoverflow - these should use
         // the cache and not perform additional queries.
         foreach ($users as $user) {
-            $result = \mod_moodleoverflow\subscriptions::fetch_discussion_subscription($moodleoverflow->id, $user->id);
+            $result = subscriptions::fetch_discussion_subscription($moodleoverflow->id, $user->id);
             $this->assertIsArray($result);
         }
         $finalcount = $DB->perf_get_reads();
@@ -1229,22 +1058,22 @@ public function test_discussion_subscription_cache_fill(): void {
                 if ($usercount % 2) {
                     continue;
                 }
-                \mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($user->id, $discussion, $modulecontext);
+                subscriptions::unsubscribe_user_from_discussion($user->id, $data, $modulecontext);
                 $usercount++;
             }
             $moodleoverflowcount++;
         }
 
         // Reset the subscription caches.
-        \mod_moodleoverflow\subscriptions::reset_moodleoverflow_cache();
-        \mod_moodleoverflow\subscriptions::reset_discussion_cache();
+        subscriptions::reset_moodleoverflow_cache();
+        subscriptions::reset_discussion_cache();
 
         $startcount = $DB->perf_get_reads();
 
         // Now fetch some subscriptions from that moodleoverflow - these should use
         // the cache and not perform additional queries.
         foreach ($users as $user) {
-            $result = \mod_moodleoverflow\subscriptions::fetch_discussion_subscription($moodleoverflow->id, $user->id);
+            $result = subscriptions::fetch_discussion_subscription($moodleoverflow->id, $user->id);
             $this->assertIsArray($result);
         }
         $finalcount = $DB->perf_get_reads();
@@ -1268,16 +1097,12 @@ public function test_moodleoverflow_subscribe_toggle_as_other_repeat_subscriptio
         // Reset the database after testing.
         $this->resetAfterTest(true);
 
-        // Create a course, with a moodleoverflow.
+        // Create a course, with a moodleoverflow and get the module context. Create a user enrolled in the course as a student.
         $course = $this->getDataGenerator()->create_course();
         $options = ['course' => $course->id, 'forcesubscribe' => MOODLEOVERFLOW_CHOOSESUBSCRIBE];
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', $options);
-
-        // Get the module context.
         $cm = get_coursemodule_from_instance('moodleoverflow', $moodleoverflow->id);
         $modulecontext = \context_module::instance($cm->id);
-
-        // Create a user enrolled in the course as a student.
         list($user) = $this->helper_create_users($course, 1);
 
         // Post a discussion to the moodleoverflow.
@@ -1286,73 +1111,52 @@ public function test_moodleoverflow_subscribe_toggle_as_other_repeat_subscriptio
         unset($post);
         $discussion->moodleoverflow = $moodleoverflow->id;
 
+        // Declare the options for the subscription tables.
+        $discussoptions = ['userid' => $user->id, 'discussion' => $discussion->id];
+        $subscriptionoptions = ['userid' => $user->id, 'moodleoverflow' => $moodleoverflow->id];
+
         // Confirm that the user is currently not subscribed to the moodleoverflow.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($user->id, $moodleoverflow, $modulecontext));
+        $this->assertFalse(subscriptions::is_subscribed($user->id, $moodleoverflow, $modulecontext));
 
         // Confirm that the user is unsubscribed from the discussion too.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribed($user->id, $moodleoverflow, $modulecontext,
-            $discussion->id));
+        $this->assertFalse(subscriptions::is_subscribed($user->id, $moodleoverflow, $modulecontext, $discussion->id));
 
         // Confirm that we have no records in either of the subscription tables.
-        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', [
-            'userid' => $user->id,
-            'moodleoverflow' => $moodleoverflow->id,
-        ]));
-        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', [
-            'userid' => $user->id,
-            'discussion' => $discussion->id,
-        ]));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
         // Subscribing to the moodleoverflow should create a record in the subscriptions table,
         // but not the moodleoverflow discussion subscriptions table.
-        \mod_moodleoverflow\subscriptions::subscribe_user($user->id, $moodleoverflow, $modulecontext);
-        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', [
-            'userid' => $user->id,
-            'moodleoverflow' => $moodleoverflow->id,
-        ]));
-        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', [
-            'userid' => $user->id,
-            'discussion' => $discussion->id,
-        ]));
+        subscriptions::subscribe_user($user->id, $moodleoverflow, $modulecontext);
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
         // Now unsubscribe from the discussion. This should return true.
         $uid = $user->id;
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($uid, $discussion, $modulecontext));
+        $this->assertTrue(subscriptions::unsubscribe_user_from_discussion($uid, $discussion, $modulecontext));
 
         // Attempting to unsubscribe again should return false because no change was made.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($uid, $discussion, $modulecontext));
+        $this->assertFalse(subscriptions::unsubscribe_user_from_discussion($uid, $discussion, $modulecontext));
 
         // Subscribing to the discussion again should return truthfully as the subscription preference was removed.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($user->id, $discussion, $modulecontext));
+        $this->assertTrue(subscriptions::subscribe_user_to_discussion($user->id, $discussion, $modulecontext));
 
         // Attempting to subscribe again should return false because no change was made.
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($user->id, $discussion, $modulecontext));
+        $this->assertFalse(subscriptions::subscribe_user_to_discussion($user->id, $discussion, $modulecontext));
 
         // Now unsubscribe from the discussion. This should return true once more.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::unsubscribe_user_from_discussion($uid, $discussion, $modulecontext));
+        $this->assertTrue(subscriptions::unsubscribe_user_from_discussion($uid, $discussion, $modulecontext));
 
         // And unsubscribing from the moodleoverflow but not as a request from the user should maintain their preference.
-        \mod_moodleoverflow\subscriptions::unsubscribe_user($user->id, $moodleoverflow, $modulecontext);
+        subscriptions::unsubscribe_user($user->id, $moodleoverflow, $modulecontext);
 
-        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', [
-            'userid' => $user->id,
-            'moodleoverflow' => $moodleoverflow->id,
-        ]));
-        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', [
-            'userid' => $user->id,
-            'discussion' => $discussion->id,
-        ]));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
 
         // Subscribing to the discussion should return truthfully because a change was made.
-        $this->assertTrue(\mod_moodleoverflow\subscriptions::subscribe_user_to_discussion($user->id, $discussion, $modulecontext));
-        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', [
-            'userid' => $user->id,
-            'moodleoverflow' => $moodleoverflow->id,
-        ]));
-        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', [
-            'userid' => $user->id,
-            'discussion' => $discussion->id,
-        ]));
+        $this->assertTrue(subscriptions::subscribe_user_to_discussion($user->id, $discussion, $modulecontext));
+        $this->assertEquals(0, $DB->count_records('moodleoverflow_subscriptions', $subscriptionoptions));
+        $this->assertEquals(1, $DB->count_records('moodleoverflow_discuss_subs', $discussoptions));
     }
 
     /**
@@ -1361,20 +1165,8 @@ public function test_moodleoverflow_subscribe_toggle_as_other_repeat_subscriptio
      * @return array
      */
     public static function is_subscribable_moodleoverflows() {
-        return [
-            [
-                'forcesubscribe' => MOODLEOVERFLOW_DISALLOWSUBSCRIBE,
-            ],
-            [
-                'forcesubscribe' => MOODLEOVERFLOW_CHOOSESUBSCRIBE,
-            ],
-            [
-                'forcesubscribe' => MOODLEOVERFLOW_INITIALSUBSCRIBE,
-            ],
-            [
-                'forcesubscribe' => MOODLEOVERFLOW_FORCESUBSCRIBE,
-            ],
-        ];
+        return [['forcesubscribe' => MOODLEOVERFLOW_DISALLOWSUBSCRIBE], ['forcesubscribe' => MOODLEOVERFLOW_CHOOSESUBSCRIBE],
+                ['forcesubscribe' => MOODLEOVERFLOW_INITIALSUBSCRIBE], ['forcesubscribe' => MOODLEOVERFLOW_FORCESUBSCRIBE], ];
     }
 
     /**
@@ -1387,7 +1179,6 @@ public static function is_subscribable_provider(): array {
         foreach (self::is_subscribable_moodleoverflows() as $moodleoverflow) {
             $data[] = [$moodleoverflow];
         }
-
         return $data;
     }
 
@@ -1407,8 +1198,7 @@ public function test_is_subscribable_logged_out($options): void {
         $options['course'] = $course->id;
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', $options);
 
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribable($moodleoverflow,
-                \context_module::instance($moodleoverflow->cmid)));
+        $this->assertFalse(subscriptions::is_subscribable($moodleoverflow, \context_module::instance($moodleoverflow->cmid)));
     }
 
     /**
@@ -1432,8 +1222,7 @@ public function test_is_subscribable_is_guest($options): void {
         $options['course'] = $course->id;
         $moodleoverflow = $this->getDataGenerator()->create_module('moodleoverflow', $options);
 
-        $this->assertFalse(\mod_moodleoverflow\subscriptions::is_subscribable($moodleoverflow,
-                \context_module::instance($moodleoverflow->cmid)));
+        $this->assertFalse(subscriptions::is_subscribable($moodleoverflow, \context_module::instance($moodleoverflow->cmid)));
     }
 
     /**
@@ -1442,22 +1231,10 @@ public function test_is_subscribable_is_guest($options): void {
      */
     public static function is_subscribable_loggedin_provider(): array {
         return [
-            [
-                ['forcesubscribe' => MOODLEOVERFLOW_DISALLOWSUBSCRIBE],
-                false,
-            ],
-            [
-                ['forcesubscribe' => MOODLEOVERFLOW_CHOOSESUBSCRIBE],
-                true,
-            ],
-            [
-                ['forcesubscribe' => MOODLEOVERFLOW_INITIALSUBSCRIBE],
-                true,
-            ],
-            [
-                ['forcesubscribe' => MOODLEOVERFLOW_FORCESUBSCRIBE],
-                false,
-            ],
+            [['forcesubscribe' => MOODLEOVERFLOW_DISALLOWSUBSCRIBE], false],
+            [['forcesubscribe' => MOODLEOVERFLOW_CHOOSESUBSCRIBE], true],
+            [['forcesubscribe' => MOODLEOVERFLOW_INITIALSUBSCRIBE], true],
+            [['forcesubscribe' => MOODLEOVERFLOW_FORCESUBSCRIBE], false],
         ];
     }
 
@@ -1484,7 +1261,7 @@ public function test_is_subscribable_loggedin($options, $expect): void {
         $this->getDataGenerator()->enrol_user($user->id, $course->id);
         $this->setUser($user);
 
-        $this->assertEquals($expect, \mod_moodleoverflow\subscriptions::is_subscribable($moodleoverflow,
-                \context_module::instance($moodleoverflow->cmid)));
+        $this->assertEquals($expect, subscriptions::is_subscribable($moodleoverflow,
+            \context_module::instance($moodleoverflow->cmid)));
     }
 }
diff --git a/tests/userstats_test.php b/tests/userstats_test.php
index 080a11dd95..037b1db1f6 100644
--- a/tests/userstats_test.php
+++ b/tests/userstats_test.php
@@ -230,7 +230,6 @@ public function test_total_anonymous(): void {
 
         // Get the current userstats to compare later.
         $olduserstats = $this->create_statstable();
-        $oldupvotesuser1 = $this->get_specific_userstats($olduserstats, $this->user1, 'receivedupvotes');
         $oldactivityuser1 = $this->get_specific_userstats($olduserstats, $this->user1, 'forumactivity');
 
         $oldupvotesuser2 = $this->get_specific_userstats($olduserstats, $this->user2, 'receivedupvotes');
diff --git a/tracking.php b/tracking.php
index b152d5d439..4c5c5b2224 100644
--- a/tracking.php
+++ b/tracking.php
@@ -25,6 +25,7 @@
 // Require needed files.
 require_once("../../config.php");
 require_once("locallib.php");
+global $CFG, $DB, $USER;
 
 // Get submitted parameters.
 $id = required_param('id', PARAM_INT);                       // The moodleoverflow to track or untrack.
@@ -34,14 +35,10 @@
 require_sesskey();
 
 // Retrieve the moodleoverflow instance to track or untrack.
-if (!$moodleoverflow = $DB->get_record("moodleoverflow", ["id" => $id])) {
-    throw new moodle_exception('invalidmoodleoverflowid', 'moodleoverflow');
-}
+$moodleoverflow = moodleoverflow_get_record_or_exception('moodleoverflow', ['id' => $id], 'invalidmoodleoverflowid');
 
 // Retrieve the course of the instance.
-if (!$course = $DB->get_record("course", ["id" => $moodleoverflow->course])) {
-    throw new moodle_exception('invalidcoursemodule');
-}
+$course = moodleoverflow_get_record_or_exception('course', ['id' => $moodleoverflow->course], 'invalidcourseid', '*', true);
 
 // Retrieve the course module of that course.
 if (!$cm = get_coursemodule_from_instance("moodleoverflow", $moodleoverflow->id, $course->id)) {
@@ -95,9 +92,7 @@
         redirect($returnpageurl, get_string('nownottracking', 'moodleoverflow', $info), 1);
 
     } else {
-        // The insertion failed.
-
-        // Print an error message.
+        // The insertion failed. Print an error message.
         throw new moodle_exception('cannottrack', 'moodleoverflow', get_local_referer(false));
     }
 
@@ -116,9 +111,7 @@
         redirect($returnto, get_string('nowtracking', 'moodleoverflow', $info), 1);
 
     } else {
-        // The deletion failed.
-
-        // Print an error message.
+        // The deletion failed. Print an error message.
         throw new moodle_exception('cannottrack', 'moodleoverflow', get_local_referer(false));
     }
 }
diff --git a/view.php b/view.php
index 4178d7913d..52b55a157a 100644
--- a/view.php
+++ b/view.php
@@ -65,7 +65,6 @@
 // Save the allowmultiplemarks setting.
 $marksetting = $DB->get_record('moodleoverflow', ['id' => $moodleoverflow->id], 'allowmultiplemarks');
 
-
 // Require a login.
 require_login($course, true, $cm);