Prevents sending queue rerendering when post notification is updated

lib/API/JSON/v1/Newsletters.php

@@ -116,7 +116,7 @@ class Newsletters extends APIEndpoint {
     }
 
     $queue = $newsletter->getQueue();
-    if($queue) {
+    if($queue && !in_array($newsletter->type, array(Newsletter::TYPE_NOTIFICATION, Newsletter::TYPE_NOTIFICATION_HISTORY))) {
       // if newsletter was previously scheduled and is now unscheduled, set its status to DRAFT and delete associated queue record
       if($newsletter->status === Newsletter::STATUS_SCHEDULED && isset($options['isScheduled']) && empty($options['isScheduled'])) {
         $queue->delete();

tests/unit/API/JSON/v1/NewslettersTest.php

@@ -169,6 +169,32 @@ class NewslettersTest extends \MailPoetTest {
     expect($updated_newsletter->subject)->equals('My Updated Newsletter');
   }
 
+  function testItDoesNotRerenderPostNotificationsUponUpdate() {
+    $sending_queue = SendingTask::create();
+    $sending_queue->newsletter_id = $this->post_notification->id;
+    $sending_queue->status = SendingQueue::STATUS_SCHEDULED;
+    $sending_queue->newsletter_rendered_body = null;
+    $sending_queue->newsletter_rendered_subject = null;
+    $sending_queue->save();
+    expect($sending_queue->getErrors())->false();
+
+    $router = new Newsletters();
+    $newsletter_data = array(
+      'id' => $this->post_notification->id,
+      'subject' => 'My Updated Newsletter',
+      'body' => Fixtures::get('newsletter_body_template'),
+    );
+
+    $response = $router->save($newsletter_data);
+    $updated_queue = SendingQueue::where('newsletter_id', $this->post_notification->id)
+      ->findOne()
+      ->asArray();
+
+    expect($response->status)->equals(APIResponse::STATUS_OK);
+    expect($updated_queue['newsletter_rendered_body'])->null();
+    expect($updated_queue['newsletter_rendered_subject'])->null();
+  }
+
   function testItCanRerenderQueueUponSave() {
     $sending_queue = SendingTask::create();
     $sending_queue->newsletter_id = $this->newsletter->id;