diff --git a/comment_notify.inc b/comment_notify.inc
index 59f5f05..db83951 100644
--- a/comment_notify.inc
+++ b/comment_notify.inc
@@ -2,17 +2,19 @@
 
 /**
  * @file
- *
  * Contains functions which utilize the database and other internal helpers.
  */
+
 use Drupal\comment\CommentInterface;
 
 /**
  * Get the notification preferences for a specific user.
  *
- * @param integer $uid
+ * @param int $uid
+ *   The user id.
+ *
  * @return mixed
- *  StdClass if found, else NULL
+ *   StdClass if found, else NULL
  */
 function comment_notify_get_user_notification_setting($uid) {
   $users = &drupal_static(__FUNCTION__);
@@ -42,21 +44,27 @@ function comment_notify_get_user_notification_setting($uid) {
   return $users[$uid];
 }
 
+/**
+ * Returns the default values of the notification settings.
+ */
 function comment_notify_get_default_notification_setting() {
-  return (object) array(
+  return (object) [
     'comment_notify' => \Drupal::config('comment_notify.settings')->get('enable_default.watcher'),
-    'node_notify' => \Drupal::config('comment_notify.settings')->get('enable_default.entity_author')
-  );
+    'node_notify' => \Drupal::config('comment_notify.settings')->get('enable_default.entity_author'),
+  ];
 }
 
 /**
  * Remove comment notification preferences for a user.
  *
- * @param integer $uid
- * @return boolean
+ * @param int $uid
+ *   The user id.
+ *
+ * @return bool
+ *   TRUE if the preferences were removed correctly, FALSE if weren't removed.
  */
 function comment_notify_delete_user_notification_setting($uid) {
-  return (bool)db_delete('comment_notify_user_settings')
+  return (bool) db_delete('comment_notify_user_settings')
     ->condition('uid', $uid)
     ->execute();
 }
@@ -64,8 +72,11 @@ function comment_notify_delete_user_notification_setting($uid) {
 /**
  * Get a user's default preference for comment notification.
  *
- * @param integer $uid
- * @return integer
+ * @param int $uid
+ *   The User ID.
+ *
+ * @return int
+ *   Return the comment preference.
  */
 function comment_notify_get_user_comment_notify_preference($uid) {
   $setting = comment_notify_get_user_notification_setting($uid);
@@ -80,8 +91,11 @@ function comment_notify_get_user_comment_notify_preference($uid) {
  *
  * This is notification on nodes where the user is the author.
  *
- * @param integer $uid
- * @return integer
+ * @param int $uid
+ *   The User ID.
+ *
+ * @return int
+ *   Return the node_notify value.
  */
 function comment_notify_get_user_node_notify_preference($uid) {
   $setting = comment_notify_get_user_notification_setting($uid);
@@ -94,16 +108,21 @@ function comment_notify_get_user_node_notify_preference($uid) {
 /**
  * Sets the notification preferences for a specific user.
  *
- * @param integer $uid
- * @param integer $node_notification
- * @param integer $comment_notification
- * @return boolean
+ * @param int $uid
+ *   The User ID.
+ * @param int $node_notification
+ *   The node notification value.
+ * @param int $comment_notification
+ *   The comment notification value.
+ *
+ * @return bool
+ *   TRUE if the notification was set correctly.
  */
 function comment_notify_set_user_notification_setting($uid, $node_notification = NULL, $comment_notification = NULL) {
   if (!$uid) {
     throw new Exception('Cannot set user preference, uid missing');
   }
-  $fields = array('uid' => $uid);
+  $fields = ['uid' => $uid];
 
   if (!is_null($node_notification)) {
     $fields['node_notify'] = $node_notification;
@@ -118,7 +137,7 @@ function comment_notify_set_user_notification_setting($uid, $node_notification =
   else {
     $query = db_insert('comment_notify_user_settings');
   }
-  return (bool)$query
+  return (bool) $query
     ->fields($fields)
     ->execute();
 }
@@ -126,70 +145,82 @@ function comment_notify_set_user_notification_setting($uid, $node_notification =
 /**
  * Add a notification against a comment.
  *
- * @param integer $cid
- * @param integer $notify
+ * @param int $cid
+ *   Comment Id.
+ * @param int $notify
+ *   The notification type.
  * @param string $notify_hash
- * @param integer|NULL $notified
+ *   The comment hash.
+ * @param int|null $notified
+ *   If the user has been already notified.
  *
- * @return boolean
+ * @return bool
+ *   TRUE if the notification was added correctly.
  */
 function comment_notify_add_notification($cid, $notify, $notify_hash, $notified) {
   // Check if comment already exist.
   $results = db_select('comment_notify', 'cn')
-    ->fields('cn', array('cid'))
+    ->fields('cn', ['cid'])
     ->condition('cn.cid', $cid)
     ->execute()
     ->fetchField();
 
   // Update comment if exist.
   if ($results) {
-    return (bool)db_update('comment_notify')
-      ->fields(array(
+    return (bool) db_update('comment_notify')
+      ->fields([
         'notify' => $notify === NULL ? 0 : $notify,
         'notify_hash' => $notify_hash,
         'notified' => $notified === NULL ? 0 : $notified,
-      ))
+      ])
       ->condition('cid', $cid)
       ->execute();
   }
 
   // Create new entry.
   else {
-    return (bool)db_insert('comment_notify')
-      ->fields(array(
+    return (bool) db_insert('comment_notify')
+      ->fields([
         'cid' => $cid,
         'notify' => $notify === NULL ? 0 : $notify,
         'notify_hash' => $notify_hash,
         'notified' => $notified === NULL ? 0 : $notified,
-      ))
+      ])
       ->execute();
   }
 }
 
 /**
- * Remove all the notifications linked with a comment
+ * Remove all the notifications linked with a comment.
  *
- * @param integer $cid
- * @return boolean
+ * @param int $cid
+ *   The comment ID.
+ *
+ * @return bool
+ *   TRUE if all the notifications were removed correctly.
  */
 function comment_notify_remove_all_notifications($cid) {
-  return (bool)db_delete('comment_notify')
+  return (bool) db_delete('comment_notify')
     ->condition('cid', $cid)
     ->execute();
 }
 
 /**
- * Updated a notification with a different notification type
+ * Updated a notification with a different notification type.
+ *
+ * @param int $cid
+ *   The comment id.
+ * @param int $notify
+ *   The value that is going to be updated.
  *
- * @param integer $cid
- * @param integer $notify
- * @return boolean
+ * @return bool
+ *   TRUE if the notification was updated correctly.
  */
 function comment_notify_update_notification($cid, $notify) {
-  return (bool)db_update('comment_notify')
-    ->fields(array(
+  return (bool) db_update('comment_notify')
+    ->fields([
       'notify' => $notify === NULL ? 0 : $notify,
-    ))
+    ])
     ->condition('cid', $cid)
     ->execute();
 }
@@ -197,12 +228,15 @@ function comment_notify_update_notification($cid, $notify) {
 /**
  * Get the type of notification for a comment notification record.
  *
- * @param integer $cid
- * @return integer
+ * @param int $cid
+ *   The comment id.
+ *
+ * @return int
+ *   Return the notification type.
  */
 function comment_notify_get_notification_type($cid) {
   return db_select('comment_notify', 'cn')
-    ->fields('cn', array('notify'))
+    ->fields('cn', ['notify'])
     ->condition('cid', $cid)
     ->execute()
     ->fetchField();
@@ -211,37 +245,42 @@ function comment_notify_get_notification_type($cid) {
 /**
  * Get a list of mails which need to be contacted for a node.
  *
- * @param integer $nid
+ * @param int $nid
+ *   The node id.
  * @param string $comment_type
+ *   The comment type.
  *
  * @return \Drupal\comment\CommentInterface[]
  *   A list of comment entities.
  */
 function comment_notify_get_watchers($nid, $comment_type) {
-  $cids = db_query("SELECT c.cid FROM {comment_field_data} c INNER JOIN {comment_notify} cn ON c.cid = cn.cid LEFT JOIN {users_field_data} u ON c.uid = u.uid WHERE c.entity_id = :nid AND c.comment_type = :comment_type AND c.status = :status AND cn.notify <> :notify AND (u.uid = 0 OR u.status = 1)", array(
+  $cids = db_query("SELECT c.cid FROM {comment_field_data} c INNER JOIN {comment_notify} cn ON c.cid = cn.cid LEFT JOIN {users_field_data} u ON c.uid = u.uid WHERE c.entity_id = :nid AND c.comment_type = :comment_type AND c.status = :status AND cn.notify <> :notify AND (u.uid = 0 OR u.status = 1)", [
     ':nid' => $nid,
     ':comment_type' => $comment_type,
     ':status' => CommentInterface::PUBLISHED,
     ':notify' => COMMENT_NOTIFY_DISABLED,
-  ))->fetchCol();
+  ])->fetchCol();
   return \Drupal::entityManager()->getStorage('comment')->loadMultiple($cids);
 }
 
 /**
- * Record that the owner of a comment notification request has already been notified.
+ * Records that the owner of a comment notification request has been notified.
  *
- * @param integer $cid
- * @return boolean
+ * @param int $comment
+ *   The comment ID.
+ *
+ * @return bool
+ *   True if it can be updated correctly.
  */
 function comment_notify_mark_comment_as_notified($comment) {
   // First, mark the passed comment (an object, so passed by reference).
   $comment->notified = 1;
 
   // Next, store this fact in the DB as well.
-  return (bool)db_update('comment_notify')
-    ->fields(array(
+  return (bool) db_update('comment_notify')
+    ->fields([
       'notified' => 1,
-    ))
+    ])
     ->condition('cid', $comment->id())
     ->execute();
 }
@@ -249,15 +288,18 @@ function comment_notify_mark_comment_as_notified($comment) {
 /**
  * Unsubscribe all comment notification requests associated with an email.
  *
- * If the email belongs to a user, it will unsubscribe all of their Comment Notify records.
- * If it does not, then it will unsubscribe all anonymous users.
+ * If the email belongs to a user, it will unsubscribe all of their Comment
+ * Notify records. If it does not, then it will unsubscribe all anonymous users.
  *
  * @param string $mail
- * @return boolean
+ *   The mail that is going to be unsubscribed.
+ *
+ * @return bool
+ *   TRUE if the comment was unsubscribed correctly.
  */
 function comment_notify_unsubscribe_by_email($mail) {
   $update_query = db_update('comment_notify');
-  $update_query->fields(array('notify' => 0));
+  $update_query->fields(['notify' => 0]);
 
   $comment_query = \Drupal::entityQuery('comment');
 
@@ -269,7 +311,7 @@ function comment_notify_unsubscribe_by_email($mail) {
   }
   $update_query->condition('cid', $comment_query->execute(), 'IN');
 
-  return (bool)$update_query->execute();
+  return (bool) $update_query->execute();
 }
 
 /**
@@ -278,16 +320,19 @@ function comment_notify_unsubscribe_by_email($mail) {
  * This is used in the unsubscribe link.
  *
  * @param string $hash
- * @return boolean
+ *   The hash that identified the comment.
+ *
+ * @return bool
+ *   Returns TRUE if the comment was unsubscribed correctly, FALSE otherwise.
  */
 function comment_notify_unsubscribe_by_hash($hash) {
   $query = db_select('comment_notify', 'cn');
   $query->join('comment_field_data', 'cf', 'cn.cid = cf.cid');
   $query->condition('cn.notify_hash', $hash)
-      ->condition('cn.notify', COMMENT_NOTIFY_DISABLED, '!=')
-      ->fields('cn', array('cid', 'notify', 'notified'))
-      ->fields('cf', array('entity_id', 'uid'))
-      ->execute()->fetchObject();
+    ->condition('cn.notify', COMMENT_NOTIFY_DISABLED, '!=')
+    ->fields('cn', ['cid', 'notify', 'notified'])
+    ->fields('cf', ['entity_id', 'uid'])
+    ->execute()->fetchObject();
   $notification = $query->execute()->fetchObject();
 
   if (empty($notification)) {
@@ -297,24 +342,24 @@ function comment_notify_unsubscribe_by_hash($hash) {
   // If this notification is at the node level and the commenter has a Drupal
   // account, delete all notifications for this node.
   if (COMMENT_NOTIFY_NODE == $notification->notify && $notification->uid) {
-    $result = db_query("SELECT cid FROM {comment_field_data} WHERE entity_id = :entity_id AND uid = :uid", array(':entity_id' => $notification->entity_id, ':uid' => $notification->uid));
+    $result = db_query("SELECT cid FROM {comment_field_data} WHERE entity_id = :entity_id AND uid = :uid", [':entity_id' => $notification->entity_id, ':uid' => $notification->uid]);
     $cids = $result->fetchCol();
 
     // Update all comment notifications to be disabled.
-    return (bool)db_update('comment_notify')
-      ->fields(array(
+    return (bool) db_update('comment_notify')
+      ->fields([
         'notify' => 0,
-      ))
+      ])
       ->condition('cid', $cids, 'IN')
       ->execute();
   }
   else {
-   // Update this notification to be disabled.
-   return (bool)db_update('comment_notify')
-     ->fields(array(
-       'notify' => 0,
-     ))
-    ->condition('notify_hash', $hash)
-    ->execute();
+    // Update this notification to be disabled.
+    return (bool) db_update('comment_notify')
+      ->fields([
+        'notify' => 0,
+      ])
+      ->condition('notify_hash', $hash)
+      ->execute();
   }
 }
diff --git a/comment_notify.install b/comment_notify.install
index 440d120..ea6d041 100644
--- a/comment_notify.install
+++ b/comment_notify.install
@@ -1,7 +1,8 @@
 <?php
+
 /**
  * @file
- * comment_notify.install.
+ * Comment_notify.install.
  */
 
 /**
@@ -16,10 +17,10 @@ function comment_notify_install() {
   // Mix in a random string to all values.
   $salt = uniqid(mt_rand(), TRUE);
   if (db_driver() == 'pgsql') {
-    $comments_select->addExpression("MD5(:salt || c.mail || COALESCE(u.mail, u.init) || c.uid || c.name || c.entity_id || c.hostname || c.cid)", 'notify_hash', array(':salt' => $salt));
+    $comments_select->addExpression("MD5(:salt || c.mail || COALESCE(u.mail, u.init) || c.uid || c.name || c.entity_id || c.hostname || c.cid)", 'notify_hash', [':salt' => $salt]);
   }
   else {
-    $comments_select->addExpression("MD5(CONCAT_WS('', :salt, c.mail, COALESCE(u.mail, u.init), c.uid, c.name, c.entity_id, c.hostname, c.cid))", 'notify_hash', array(':salt' => $salt));
+    $comments_select->addExpression("MD5(CONCAT_WS('', :salt, c.mail, COALESCE(u.mail, u.init), c.uid, c.name, c.entity_id, c.hostname, c.cid))", 'notify_hash', [':salt' => $salt]);
   }
   db_insert('comment_notify')->from($comments_select)->execute();
 
@@ -31,64 +32,72 @@ function comment_notify_install() {
  * Implements hook_schema().
  */
 function comment_notify_schema() {
-  $schema['comment_notify'] = array(
-    'description' => t('Stores information about which commenters on the site have subscriped to followup emails.'),
-    'fields' => array(
-      'cid' => array(
+  $schema['comment_notify'] = [
+    'description' => 'Stores information about which commenters on the site have subscriped to followup emails.',
+    'fields' => [
+      'cid' => [
         'type' => 'int',
         'unsigned' => TRUE,
         'description' => 'The comment id from {comments}.cid',
         'not null' => TRUE,
-        'disp-width' => '11'),
-      'notify' => array(
+        'disp-width' => '11',
+      ],
+      'notify' => [
         'type' => 'int',
         'description' => 'An integer indicating the type of subscription: 0 means not subscribed, 1 means subscribed to all comments, and 2 means only subscribed to replies of this comment.',
         'size' => 'tiny',
         'not null' => TRUE,
-        'disp-width' => '11'),
-      'notify_hash' => array(
+        'disp-width' => '11',
+      ],
+      'notify_hash' => [
         'type' => 'varchar',
         'description' => 'A hash of unique information about the commenter.  Used for unsubscribing users.',
         'length' => '128',
         'not null' => TRUE,
-        'default' => ''),
-      'notified' => array(
+        'default' => '',
+      ],
+      'notified' => [
         'type' => 'int',
         'description' => 'A boolean indicator for whether or not a notification for the comment has been sent: 1 means yes, 0 means no.',
         'size' => 'tiny',
         'not null' => TRUE,
         'default' => 0,
-        'disp-width' => '11'),
-    ),
-    'primary key' => array('cid'),
-    'indexes' => array(
-      'notify_hash' => array('notify_hash')),
-  );
-  $schema['comment_notify_user_settings'] = array(
-    'fields' => array(
-        'uid' => array(
-          'type' => 'int',
-          'unsigned' => TRUE,
-          'description' => 'The user id from {users}.cid',
-          'not null' => TRUE,
-          'disp-width' => '11'),
-        'node_notify' => array(
-          'type' => 'int',
-          'description' => 'An integer indicating the default type of subscription: 0 means not subscribed, 1 means subscribed to all comments, and 2 means only subscribed to replies of this comment.',
-          'size' => 'tiny',
-          'not null' => TRUE,
-          'default' => 0,
-          'disp-width' => '11'),
-        'comment_notify' => array(
-          'type' => 'int',
-          'description' => 'An integer indicating the default type of subscription: 0 means not subscribed, 1 means subscribed to all comments, and 2 means only subscribed to replies of this comment.',
-          'size' => 'tiny',
-          'not null' => TRUE,
-          'default' => 0,
-          'disp-width' => '11'),
-    ),
-    'primary key' => array('uid'),
-  );
+        'disp-width' => '11',
+      ],
+    ],
+    'primary key' => ['cid'],
+    'indexes' => [
+      'notify_hash' => ['notify_hash'],
+    ],
+  ];
+  $schema['comment_notify_user_settings'] = [
+    'fields' => [
+      'uid' => [
+        'type' => 'int',
+        'unsigned' => TRUE,
+        'description' => 'The user id from {users}.cid',
+        'not null' => TRUE,
+        'disp-width' => '11',
+      ],
+      'node_notify' => [
+        'type' => 'int',
+        'description' => 'An integer indicating the default type of subscription: 0 means not subscribed, 1 means subscribed to all comments, and 2 means only subscribed to replies of this comment.',
+        'size' => 'tiny',
+        'not null' => TRUE,
+        'default' => 0,
+        'disp-width' => '11',
+      ],
+      'comment_notify' => [
+        'type' => 'int',
+        'description' => 'An integer indicating the default type of subscription: 0 means not subscribed, 1 means subscribed to all comments, and 2 means only subscribed to replies of this comment.',
+        'size' => 'tiny',
+        'not null' => TRUE,
+        'default' => 0,
+        'disp-width' => '11',
+      ],
+    ],
+    'primary key' => ['uid'],
+  ];
 
   return $schema;
 }
diff --git a/comment_notify.migrate.inc b/comment_notify.migrate.inc
index 92b406f..064ea54 100644
--- a/comment_notify.migrate.inc
+++ b/comment_notify.migrate.inc
@@ -9,31 +9,35 @@
  * Field handler.
  */
 class CommentNotifyMigrationHandler extends MigrateDestinationHandler {
+
+  /**
+   * {@inheritdoc}
+   */
   public function __construct() {
-    $this->registerTypes(array('comment'));
+    $this->registerTypes(['comment']);
   }
 
   /**
    * Make the destination field visible.
    */
   public function fields() {
-    return array(
+    return [
       'notify' => t('Comment Notify: Whether to send notifications for this comment'),
       'notified' => t('Comment Notify: Whether notifications have been sent for this comment'),
       'notify_hash' => t('Comment Notify: Hash representing this notification'),
-    );
+    ];
   }
 
   /**
    * Implements MigrateDestinationHandler::prepare().
    *
    * @param $comment
-   *  The comment object being prepared for saving.
+   *   The comment object being prepared for saving.
    * @param $row
-   *  Raw source data for the migration - ignored.
+   *   Raw source data for the migration - ignored.
    */
   public function prepare($comment, $row) {
-    // By default, set notifications off
+    // By default, set notifications off.
     if (!isset($comment->notify)) {
       $comment->notify = 0;
     }
@@ -46,23 +50,24 @@ class CommentNotifyMigrationHandler extends MigrateDestinationHandler {
    * Implements MigrateDestinationHandler::complete().
    *
    * @param $comment
-   *  The comment object taht was just saved.
+   *   The comment object taht was just saved.
    * @param $row
-   *  Raw source data for the migration - ignored.
+   *   Raw source data for the migration - ignored.
    */
   public function complete($comment, $row) {
     if (!isset($comment->notified) || $comment->notified) {
       comment_notify_mark_comment_as_notified($comment);
     }
   }
+
 }
 
-/*
- * Implementats hook_migrate_api().
+/**
+ * Implements hook_migrate_api().
  */
 function comment_notify_migrate_api() {
-  $api = array(
+  $api = [
     'api' => 2,
-  );
+  ];
   return $api;
 }
diff --git a/comment_notify.module b/comment_notify.module
index eebacd2..8ea01d8 100644
--- a/comment_notify.module
+++ b/comment_notify.module
@@ -2,10 +2,12 @@
 
 /**
  * @file
+ * This module provides comment follow-up e-mail notifications.
  *
- * This module provides comment follow-up e-mail notification for anonymous and registered users.
+ * It works for anonymous and registered users.
  */
 
+use Drupal\Core\Entity\EntityInterface;
 use Drupal\comment\CommentInterface;
 use Drupal\Component\Render\PlainTextOutput;
 use Drupal\Component\Utility\Html;
@@ -24,10 +26,10 @@ define('COMMENT_NOTIFY_COMMENT', 2);
  * Provide an array of available options for notification on a comment.
  */
 function _comment_notify_options() {
-  $total_options = array(
+  $total_options = [
     COMMENT_NOTIFY_NODE     => t('All comments'),
-    COMMENT_NOTIFY_COMMENT  => t('Replies to my comment')
-  );
+    COMMENT_NOTIFY_COMMENT  => t('Replies to my comment'),
+  ];
 
   $selected_options = array_filter(\Drupal::config('comment_notify.settings')->get('available_alerts'));
   $available_options = array_intersect_key($total_options, $selected_options);
@@ -35,7 +37,9 @@ function _comment_notify_options() {
   return $available_options;
 }
 
-
+/**
+ * Add the comment_notify fields in the comment form.
+ */
 function comment_notify_form_comment_form_alter(&$form, FormStateInterface $form_state, $form_id) {
   $user = \Drupal::currentUser();
   if (!($user->hasPermission('subscribe to comments') || $user->hasPermission('administer comments'))) {
@@ -45,7 +49,7 @@ function comment_notify_form_comment_form_alter(&$form, FormStateInterface $form
   /** @var \Drupal\Core\Entity\EntityInterface $commented_entity */
   $commented_entity = $form_state->getFormObject()->getEntity()->getCommentedEntity();
 
-  // Only add the checkbox if this is an enabled content type
+  // Only add the checkbox if this is an enabled content type.
   $enabled_types = \Drupal::config('comment_notify.settings')->get('node_types');
   if (!in_array($commented_entity->bundle(), $enabled_types)) {
     return;
@@ -54,7 +58,8 @@ function comment_notify_form_comment_form_alter(&$form, FormStateInterface $form
   $available_options = _comment_notify_options();
   // Add the checkbox for anonymous users.
   if ($user->isAnonymous()) {
-    // If anonymous users can't enter their e-mail don't tempt them with the checkbox.
+    // If anonymous users can't enter their e-mail don't tempt them with the
+    // checkbox.
     if (empty($form['author']['mail'])) {
       return;
     }
@@ -64,26 +69,27 @@ function comment_notify_form_comment_form_alter(&$form, FormStateInterface $form
   $preference = comment_notify_get_user_comment_notify_preference($user->id());
 
   // If you want to hide this on your site see http://drupal.org/node/322482
-  $form['comment_notify_settings'] = array(
+  $form['comment_notify_settings'] = [
     '#attached' => ['library' => ['comment_notify/comment_notify']],
-  );
-  $form['comment_notify_settings']['notify'] = array(
+  ];
+  $form['comment_notify_settings']['notify'] = [
     '#type' => 'checkbox',
     '#title' => t('Notify me when new comments are posted'),
     '#default_value' => (bool) $preference,
-  );
+  ];
 
-  $form['comment_notify_settings']['notify_type'] = array(
+  $form['comment_notify_settings']['notify_type'] = [
     '#type' => 'radios',
     '#options' => $available_options,
     '#default_value' => $preference != "none" ? $preference : 1,
-  );
+  ];
   if (count($available_options) == 1) {
     $form['comment_notify_settings']['notify_type']['#type'] = 'hidden';
     $form['comment_notify_settings']['notify_type']['#value'] = key($available_options);
   }
 
-  // If this is an existing comment we set the default value based on their selection last time.
+  // If this is an existing comment we set the default value based on their
+  // selection last time.
   /** @var \Drupal\comment\CommentInterface $comment */
   $comment = $form_state->getFormObject()->getEntity();
   if (!$comment->isNew()) {
@@ -100,15 +106,22 @@ function comment_notify_form_comment_form_alter(&$form, FormStateInterface $form
   $form['actions']['submit']['#submit'][] = '_comment_notify_submit_comment_form';
 }
 
+/**
+ * Checks if the values used in the comment_notify fields are valid.
+ */
 function comment_notify_comment_validate(&$form, FormStateInterface $form_state) {
   $user = \Drupal::currentUser();
   // We assume that if they are non-anonymous then they have a valid mail.
-  // For anonymous users, though, we verify that they entered a mail and let comment.module validate it is real.
+  // For anonymous users, though, we verify that they entered a mail and let
+  // comment.module validate it is real.
   if ($user->isAnonymous() && $form['comment_notify_settings']['notify']['#value'] && empty($form['author']['mail']['#value'])) {
     $form_state->setErrorByName('mail', t('If you want to subscribe to comments you must supply a valid e-mail address.'));
   }
 }
 
+/**
+ * Sends the mail alerts if necessary.
+ */
 function comment_notify_comment_publish($comment) {
   // And send notifications - the real purpose of the module.
   _comment_notify_mailalert($comment);
@@ -177,14 +190,16 @@ function comment_notify_comment_insert(CommentInterface $comment) {
   }
 }
 
+/**
+ * Deletes all the notifications when a comment is deleted.
+ */
 function comment_notify_comment_delete(CommentInterface $comment) {
   module_load_include('inc', 'comment_notify', 'comment_notify');
   comment_notify_remove_all_notifications($comment->id());
 }
 
-
 /**
- * Implement hook_form_alter().
+ * Implements hook_form_alter().
  */
 function comment_notify_form_user_form_alter(&$form, FormStateInterface &$form_state, $form_id) {
   module_load_include('inc', 'comment_notify', 'comment_notify');
@@ -204,48 +219,48 @@ function comment_notify_form_user_form_alter(&$form, FormStateInterface &$form_s
 
   // If the user cannot create nodes nor has the 'subscribe to comments'
   // permission then there is no need to alter the user_form.
-  if ((!\Drupal::currentUser()->hasPermission('administer nodes') && $nodes === FALSE) && ($user->hasPermission( 'subscribe to comments') === FALSE)) {
+  if ((!\Drupal::currentUser()->hasPermission('administer nodes') && $nodes === FALSE) && ($user->hasPermission('subscribe to comments') === FALSE)) {
     return;
   }
 
-  $form['comment_notify_settings'] = array(
+  $form['comment_notify_settings'] = [
     '#type' => 'details',
     '#title' => t('Comment follow-up notification settings'),
     '#weight' => 4,
     '#open' => TRUE,
-  );
+  ];
 
   if (\Drupal::currentUser()->hasPermission('administer nodes') || $nodes) {
-    $form['comment_notify_settings']['node_notify'] = array(
+    $form['comment_notify_settings']['node_notify'] = [
       '#type' => 'checkbox',
       '#title' => t('Receive content follow-up notification e-mails'),
       '#default_value' => isset($notify_settings->node_notify) ? $notify_settings->node_notify : NULL,
-      '#description' => t('Check this box to receive an e-mail notification for follow-ups on your content. You can not disable notifications for individual threads.')
-    );
+      '#description' => t('Check this box to receive an e-mail notification for follow-ups on your content. You can not disable notifications for individual threads.'),
+    ];
   }
   else {
-    $form['comment_notify_settings']['node_notify'] = array(
+    $form['comment_notify_settings']['node_notify'] = [
       '#type' => 'hidden',
       '#value' => COMMENT_NOTIFY_DISABLED,
-    );
+    ];
   }
 
   if ($user->hasPermission('subscribe to comments')) {
     $available_options[COMMENT_NOTIFY_DISABLED] = t('No notifications');
     $available_options += _comment_notify_options();
-    $form['comment_notify_settings']['comment_notify'] = array(
+    $form['comment_notify_settings']['comment_notify'] = [
       '#type' => 'select',
       '#title' => t('Receive comment follow-up notification e-mails'),
-      '#default_value' => isset ($notify_settings->comment_notify) ? $notify_settings->comment_notify : NULL,
+      '#default_value' => isset($notify_settings->comment_notify) ? $notify_settings->comment_notify : NULL,
       '#options' => $available_options,
-      '#description' => t("Check this box to receive e-mail notification for follow-up comments to comments you posted. You can later disable this on a post-by-post basis... so if you leave this to YES, you can still disable follow-up notifications for comments you don't want follow-up mails anymore - i.e. for very popular posts.")
-    );
+      '#description' => t("Check this box to receive e-mail notification for follow-up comments to comments you posted. You can later disable this on a post-by-post basis... so if you leave this to YES, you can still disable follow-up notifications for comments you don't want follow-up mails anymore - i.e. for very popular posts."),
+    ];
   }
   else {
-    $form['comment_notify_settings']['comment_notify'] = array(
+    $form['comment_notify_settings']['comment_notify'] = [
       '#type' => 'hidden',
       '#value' => COMMENT_NOTIFY_DISABLED,
-    );
+    ];
   }
   $form['actions']['submit']['#submit'][] = '_comment_notify_submit_user_form';
 }
@@ -268,10 +283,11 @@ function _comment_notify_submit_user_form(array &$form, FormStateInterface $form
 /**
  * Implements hook_user_delete().
  */
-function comment_notify_user_predelete(\Drupal\Core\Entity\EntityInterface $entity) {
+function comment_notify_user_predelete(EntityInterface $entity) {
   // This hook is invoked when the account is deleted.
   comment_notify_remove_user_settings($entity->id());
 }
+
 /**
  * Implements hook_user_cancel().
  */
@@ -281,7 +297,7 @@ function comment_notify_user_cancel($edit, $account, $method) {
 }
 
 /**
- * Remove the user settings of of the user with the given $uid
+ * Remove the user settings of of the user with the given $uid.
  *
  * @param int $uid
  *   The user id.
@@ -300,7 +316,7 @@ function comment_notify_comment_load($comments) {
   $query->join('comment_field_data', 'c', 'c.cid = cn.cid');
   $query->leftJoin('users_field_data', 'u', 'c.uid = u.uid');
   $query->condition('c.cid', array_keys($comments), 'IN');
-  $query->fields('cn', array('cid', 'notify', 'notify_hash', 'notified'));
+  $query->fields('cn', ['cid', 'notify', 'notify_hash', 'notified']);
   $query->addField('c', 'mail', 'cmail');
   $query->addField('u', 'init', 'uinit');
   $query->addField('u', 'mail', 'umail');
@@ -343,7 +359,7 @@ function _comment_notify_mailalert(CommentInterface $comment) {
   /** @var \Drupal\node\NodeInterface $node */
   $node = \Drupal::entityManager()->getStorage('node')->load($nid);
 
-  // No mails if this is not an enabled content type
+  // No mails if this is not an enabled content type.
   $enabled_types = $config->get('node_types');
   if (!in_array($node->bundle(), $enabled_types) && !empty($enabled_types)) {
     return;
@@ -358,14 +374,15 @@ function _comment_notify_mailalert(CommentInterface $comment) {
   else {
     $comment_mail = $comment->getAuthorEmail();
   }
-  $sent_to = array();
+  $sent_to = [];
 
   // Send to a subscribed author if they are not the current commenter.
   $author = $node->getOwner();
   $author_notify_settings = comment_notify_get_user_notification_setting($author->id()) ?: comment_notify_get_default_notification_setting();
 
   // Do they explicitly want this? Or is it default to send to users?
-  // Is the comment author not the node author? Do they have access? Do they have an email (e.g. anonymous)?
+  // Is the comment author not the node author? Do they have access? Do they
+  // have an email (e.g. anonymous)?
   if (
     (
       (!empty($author_notify_settings->node_notify) && $author_notify_settings->node_notify == 1)
@@ -405,15 +422,20 @@ function _comment_notify_mailalert(CommentInterface $comment) {
     }
 
     if ($mail != $comment_mail && !in_array(strtolower($mail), $sent_to) && ($alert->getOwnerId() != $comment->getOwnerId() || $alert->getOwnerId() == 0)) {
-      $message = array();
+      $message = [];
 
-      // Make sure they have access to this node before showing a bunch of node information.
+      // Make sure they have access to this node before showing a bunch of node
+      // information.
       if (!$node->access('view', $recipient_user)) {
         continue;
       }
 
       $raw_values = $config->get('mail_templates.watcher');
-      $token_data = ['comment' => $comment, 'node' => $node, 'comment-subscribed' => $alert];
+      $token_data = [
+        'comment' => $comment,
+        'node' => $node,
+        'comment-subscribed' => $alert,
+      ];
       $message['subject'] = PlainTextOutput::renderFromHtml(\Drupal::token()->replace($raw_values['subject'], $token_data));
       $message['body'] = \Drupal::token()->replace($raw_values['body'], $token_data);
 
@@ -467,29 +489,30 @@ function comment_notify_get_unsubscribe_url(CommentInterface $comment) {
   }
   return NULL;
 }
+
 /**
  * Implements hook_field_extra_fields().
  */
 function comment_notify_entity_extra_field_info() {
   module_load_include('inc', 'comment_notify', 'comment_notify');
-  $extras = array();
+  $extras = [];
 
   foreach (\Drupal::config('comment_notify.settings')->get('node_types') as $node_type) {
     $comment_field = FieldConfig::loadByName('node', $node_type, 'comment');
     if ($comment_field) {
       $comment_type = $comment_field->getSetting('comment_type');
-      $extras['comment'][$comment_type]['form']['comment_notify_settings'] = array(
+      $extras['comment'][$comment_type]['form']['comment_notify_settings'] = [
         'label' => t('Comment Notify settings'),
-        'description' => t('@node_type settings for Comment Notify', array('@node_type' => NodeType::load($node_type)->label())),
+        'description' => t('@node_type settings for Comment Notify', ['@node_type' => NodeType::load($node_type)->label()]),
         'weight' => 1,
-      );
+      ];
     }
   }
 
-  $extras['user']['user']['form']['comment_notify_settings'] = array(
+  $extras['user']['user']['form']['comment_notify_settings'] = [
     'label' => t('Comment Notify settings'),
     'description' => t('User settings for Comment Notify'),
     'weight' => 4,
-  );
+  ];
   return $extras;
 }
diff --git a/comment_notify.tokens.inc b/comment_notify.tokens.inc
index fcb66a6..1b2e206 100644
--- a/comment_notify.tokens.inc
+++ b/comment_notify.tokens.inc
@@ -4,6 +4,7 @@
  * @file
  * Builds placeholder replacement tokens for comment_notify.module.
  */
+
 use Drupal\Core\Render\BubbleableMetadata;
 
 /**
@@ -11,18 +12,18 @@ use Drupal\Core\Render\BubbleableMetadata;
  */
 function comment_notify_token_info() {
   // Comment tokens.
-  $info['tokens']['comment']['unsubscribe-url'] = array(
+  $info['tokens']['comment']['unsubscribe-url'] = [
     'name' => t('Unsubscribe URL'),
     'description' => t('The URL to disable notifications for the comment.'),
     'type' => 'url',
-  );
+  ];
 
   // Comment subscriber token type (extends the comment token type).
-  $info['types']['comment-subscribed'] = array(
+  $info['types']['comment-subscribed'] = [
     'name' => t('Subscribed comment'),
     'description' => t('Tokens related to a comment that is subscribed to new comments.'),
     'type' => 'comment',
-  );
+  ];
 
   return $info;
 }
@@ -30,8 +31,8 @@ function comment_notify_token_info() {
 /**
  * Implements hook_tokens().
  */
-function comment_notify_tokens($type, $tokens, array $data = array(), array $options = array(), BubbleableMetadata $bubbleable_metadata) {
-  $url_options = array('absolute' => TRUE);
+function comment_notify_tokens($type, $tokens, array $data = [], array $options = [], BubbleableMetadata $bubbleable_metadata) {
+  $url_options = ['absolute' => TRUE];
   if (isset($options['language'])) {
     $url_options['language'] = $options['language'];
     $language_code = $options['language']->language;
@@ -41,7 +42,7 @@ function comment_notify_tokens($type, $tokens, array $data = array(), array $opt
   }
   $sanitize = !empty($options['sanitize']);
 
-  $replacements = array();
+  $replacements = [];
 
   if ($type == 'comment' && !empty($data['comment'])) {
     $comment = $data['comment'];
@@ -58,13 +59,13 @@ function comment_notify_tokens($type, $tokens, array $data = array(), array $opt
 
     // [comment:unsubscribe-url:*] chained token replacements.
     if (($unsubscribe_url_tokens = \Drupal::token()->findWithPrefix($tokens, 'unsubscribe-url')) && $unsubscribe_url = comment_notify_get_unsubscribe_url($comment)) {
-      $replacements += \Drupal::token()->generate('url', $unsubscribe_url_tokens, array('path' => $unsubscribe_url), $options, $bubbleable_metadata);
+      $replacements += \Drupal::token()->generate('url', $unsubscribe_url_tokens, ['path' => $unsubscribe_url], $options, $bubbleable_metadata);
     }
   }
 
   // Comment subscriber tokens (pass through to comment token replacement).
   if ($type == 'comment-subscribed' && !empty($data['comment-subscribed'])) {
-    $replacements += \Drupal::token()->generate('comment', $tokens, array('comment' => $data['comment-subscribed']), $options, $bubbleable_metadata);
+    $replacements += \Drupal::token()->generate('comment', $tokens, ['comment' => $data['comment-subscribed']], $options, $bubbleable_metadata);
   }
 
   return $replacements;
diff --git a/src/Controller/CommentNotifyController.php b/src/Controller/CommentNotifyController.php
index 0b7bb85..291cf50 100644
--- a/src/Controller/CommentNotifyController.php
+++ b/src/Controller/CommentNotifyController.php
@@ -15,7 +15,8 @@ class CommentNotifyController extends ControllerBase {
    * @param string $hash
    *   A hash identifying the notification entry to disable.
    *
-   * @return \Drupal\Core\StringTranslation\TranslatableMarkup
+   * @return array
+   *   A renderable array.
    */
   public function disable($hash) {
     module_load_include('inc', 'comment_notify', 'comment_notify');
diff --git a/src/Form/CommentNotifySettings.php b/src/Form/CommentNotifySettings.php
index 0b7c3b4..cacd433 100644
--- a/src/Form/CommentNotifySettings.php
+++ b/src/Form/CommentNotifySettings.php
@@ -29,6 +29,9 @@ class CommentNotifySettings extends ConfigFormBase {
     return ['comment_notify.settings'];
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function buildForm(array $form, FormStateInterface $form_state) {
     $config = $this->config('comment_notify.settings');
 
@@ -150,6 +153,9 @@ class CommentNotifySettings extends ConfigFormBase {
     return parent::buildForm($form, $form_state);
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function validateForm(array &$form, FormStateInterface $form_state) {
     if (!array_filter($form_state->getValue('available_alerts'))) {
       $form_state->setErrorByName('available_alerts', 'You must enable at least one subscription mode.');
@@ -164,8 +170,20 @@ class CommentNotifySettings extends ConfigFormBase {
       ->set('node_types', array_keys(array_filter($form_state->getValue('node_types'))))
       ->set('available_alerts', $form_state->getValue('available_alerts'))
       ->set('enable_default', $form_state->getValue('enable_default'))
-      ->set('mail_templates.watcher.body', $form_state->getValue(['mail_templates', 'watcher', 'body']))
-      ->set('mail_templates.entity_author.body', $form_state->getValue(['mail_templates', 'entity_author', 'body']))
+      ->set('mail_templates.watcher.body', $form_state->getValue(
+        [
+          'mail_templates',
+          'watcher',
+          'body',
+        ]
+      ))
+      ->set('mail_templates.entity_author.body', $form_state->getValue(
+        [
+          'mail_templates',
+          'entity_author',
+          'body',
+        ]
+      ))
       ->save();
     parent::submitForm($form, $form_state);
   }
diff --git a/src/Form/CommentNotifyUnsubscribe.php b/src/Form/CommentNotifyUnsubscribe.php
index 34afda3..473d9e9 100644
--- a/src/Form/CommentNotifyUnsubscribe.php
+++ b/src/Form/CommentNotifyUnsubscribe.php
@@ -4,7 +4,6 @@ namespace Drupal\comment_notify\Form;
 
 use Drupal\Core\Form\FormBase;
 use Drupal\Core\Form\FormStateInterface;
-use Drupal\Core\Render\Element;
 
 /**
  * Unsubscribe form for Comment Notify.
@@ -44,7 +43,7 @@ class CommentNotifyUnsubscribe extends FormBase {
     module_load_include('inc', 'comment_notify', 'comment_notify');
     $email = trim($form_state->getValue(['email']));
     $comments = comment_notify_unsubscribe_by_email($email);
-    // Update the admin about the state of this comment notification subscription.
+    // Update the admin about the state of the subscription.
     if ($comments == 0) {
       drupal_set_message($this->t("There were no active comment notifications for that email."));
     }
diff --git a/tests/src/Functional/CommentNotifyAnonymousTest.php b/tests/src/Functional/CommentNotifyAnonymousTest.php
index b35a144..179b8b2 100644
--- a/tests/src/Functional/CommentNotifyAnonymousTest.php
+++ b/tests/src/Functional/CommentNotifyAnonymousTest.php
@@ -11,6 +11,9 @@ use Drupal\Core\Session\AccountInterface;
  */
 class CommentNotifyAnonymousTest extends CommentNotifyTestBase {
 
+  /**
+   * {@inheritdoc}
+   */
   protected function setUp() {
     parent::setUp();
 
@@ -28,8 +31,7 @@ class CommentNotifyAnonymousTest extends CommentNotifyTestBase {
   }
 
   /**
-   * Tests that the mail must be required if an anonymous user wants
-   * to receive notifications.
+   * Tests that the mail is required for anonymous users.
    */
   public function testMail() {
     /** @var \Drupal\node\Entity\Node $node */
@@ -146,18 +148,6 @@ class CommentNotifyAnonymousTest extends CommentNotifyTestBase {
     );
     $captured_emails = $this->container->get('state')->get('system.test_mail_collector');
     $this->assertEmpty($captured_emails, 'No notifications has been sent.');
-
-
-    // @TODO Move this test to the settings form.
-//    \Drupal::configFactory()->getEditable('comment_notify.settings')->set('available_alerts', [1 => FALSE, 2 => TRUE])->save();
-//    $subscribe_0 = ['notify' => TRUE];
-//    $contact_0 = ['mail' => $this->getRandomEmailAddress()];
-//    $anonymous_comment_0 = $this->postComment($node->toUrl()->toString(), $this->randomMachineName(), $this->randomMachineName(), $subscribe_0, $contact_0);
-//
-//    // Confirm that the notification is saved.
-//    $result = comment_notify_get_notification_type($anonymous_comment_0['id']);
-//    $this->assertEquals($result, 2, 'Notify selection option 0 is saved properly.');
-
   }
 
 }
diff --git a/tests/src/Functional/CommentNotifyTestBase.php b/tests/src/Functional/CommentNotifyTestBase.php
index 65cf6ee..b0193c6 100644
--- a/tests/src/Functional/CommentNotifyTestBase.php
+++ b/tests/src/Functional/CommentNotifyTestBase.php
@@ -19,7 +19,7 @@ abstract class CommentNotifyTestBase extends BrowserTestBase {
   /**
    * Admin User.
    *
-   * @var \Drupal\user\Entity\User $adminUser
+   * @var \Drupal\user\Entity\User
    */
   protected $adminUser;
 
@@ -64,8 +64,8 @@ abstract class CommentNotifyTestBase extends BrowserTestBase {
   /**
    * Post comment.
    *
-   * @param \Drupal\node\NodeInterface $node
-   *   Node to post comment on.
+   * @param string $url
+   *   The url where the comment will be submitted.
    * @param string $subject
    *   Comment subject.
    * @param string $comment
@@ -77,9 +77,9 @@ abstract class CommentNotifyTestBase extends BrowserTestBase {
    *   array of values to set contact info.
    *
    * @return array|bool
-   *    return an array with the comment or false if the post comment fails.
+   *   return an array with the comment or false if the post comment fails.
    */
-  protected function postComment($url, $subject, $comment, $notify, $contact = NULL) {
+  protected function postComment($url, $subject, $comment, array $notify, $contact = NULL) {
     $edit = [];
     $edit['subject[0][value]'] = $subject;
     $edit['comment_body[0][value]'] = $comment;
@@ -94,7 +94,7 @@ abstract class CommentNotifyTestBase extends BrowserTestBase {
 
     $this->drupalPostForm($url, $edit, t('Save'));
 
-    $match = array();
+    $match = [];
     // Get comment ID.
     preg_match('/#comment-([^"]+)/', $this->getURL(), $match);
 
@@ -119,12 +119,12 @@ abstract class CommentNotifyTestBase extends BrowserTestBase {
    * Checks current page for specified comment.
    *
    * @param object $comment
-   *    Comment object.
+   *   Comment object.
    * @param bool $reply
-   *    The comment is a reply to another comment.
+   *   The comment is a reply to another comment.
    *
    * @return bool
-   *    Comment found.
+   *   Comment found.
    */
   protected function commentExists($comment, $reply = FALSE) {
     if ($comment && is_object($comment)) {
@@ -151,7 +151,7 @@ abstract class CommentNotifyTestBase extends BrowserTestBase {
   /**
    * Returns a randomly generated valid email address.
    *
-   * @return string.
+   * @return string
    *   A random email.
    */
   public function getRandomEmailAddress() {
diff --git a/tests/src/Functional/CommentNotifyUserPreferencesTest.php b/tests/src/Functional/CommentNotifyUserPreferencesTest.php
index 5206031..f11644d 100644
--- a/tests/src/Functional/CommentNotifyUserPreferencesTest.php
+++ b/tests/src/Functional/CommentNotifyUserPreferencesTest.php
@@ -14,12 +14,14 @@ class CommentNotifyUserPreferencesTest extends CommentNotifyTestBase {
   /**
    * Authenticated User.
    *
-   * @var \Drupal\user\Entity\User $authenticatedUser
+   * @var \Drupal\user\Entity\User
    */
   protected $authenticatedUser;
 
   /**
    * Permissions required by the module.
+   *
+   * @var array
    */
   protected $permissions = [
     'post comments',
@@ -27,14 +29,18 @@ class CommentNotifyUserPreferencesTest extends CommentNotifyTestBase {
     'subscribe to comments',
   ];
 
+  /**
+   * {@inheritdoc}
+   */
   protected function setUp() {
     parent::setUp();
     $this->authenticatedUser = $this->drupalCreateUser($this->permissions);
   }
 
   /**
-   * The User's comment notify box should display different options depending
-   * the permissions of the user.
+   * Tests that the comment notify box is displayed correctly.
+   *
+   * It should display different options depending the permissions of the user.
    */
   public function testUserCommentNotifyBox() {
     // The user hasn't the subscribe to comments permission nor the 'administer
@@ -125,6 +131,9 @@ class CommentNotifyUserPreferencesTest extends CommentNotifyTestBase {
     $this->drupalLogout();
   }
 
+  /**
+   * Tests the "Comment Follow-up notifications" options.
+   */
   public function testsCommentFollowUpsNotifications() {
     $this->drupalLogin($this->authenticatedUser);
     $this->drupalGet($this->authenticatedUser->toUrl('edit-form')->toString());
@@ -171,7 +180,7 @@ class CommentNotifyUserPreferencesTest extends CommentNotifyTestBase {
 
     // Tests that the option is present in the user profile if the user has the
     // 'administer nodes' permission.
-    $permissions = array_merge($this->permissions,['administer nodes']);
+    $permissions = array_merge($this->permissions, ['administer nodes']);
     $this->authenticatedUser = $this->createUser($permissions);
     $this->drupalLogin($this->authenticatedUser);
     $this->drupalGet($this->authenticatedUser->toUrl('edit-form')->toString());
@@ -243,8 +252,7 @@ class CommentNotifyUserPreferencesTest extends CommentNotifyTestBase {
   }
 
   /**
-   * Test that when the user account is canceled or deleted all the settings
-   * related with the CommentNotify module are deleted.
+   * Tests that when a user is canceled all the notifications are deleted.
    */
   public function testUserCancelAccount() {
     $cancel_method_options = [