Render newsletters without clicked links

[MAILPOET-1571]

lib/Cron/Workers/StatsNotifications/Worker.php

@@ -100,11 +100,11 @@ class Worker {
       ->withStatistics();
   }
 
-  private function prepareContext(Newsletter $newsletter, NewsletterLink $link) {
+  private function prepareContext(Newsletter $newsletter, NewsletterLink $link = null) {
     $clicked = ($newsletter->statistics['clicked'] * 100) / $newsletter->total_sent;
     $opened = ($newsletter->statistics['opened'] * 100) / $newsletter->total_sent;
     $unsubscribed = ($newsletter->statistics['unsubscribed'] * 100) / $newsletter->total_sent;
-    return [
+    $context =  [
       'subject' => $newsletter->subject,
       'preheader' => sprintf(_x(
         '%1$s%% opens, %2$s%% clicks, %3$s%% unsubscribes in a nutshell.', 'newsletter open rate, click rate and unsubscribe rate', 'mailpoet'),
@@ -112,14 +112,18 @@ class Worker {
         number_format($opened, 2),
         number_format($unsubscribed, 2)
       ),
-      'topLinkClicks' => (int)$link->clicksCount,
-      'topLink' => $link->url,
+      $context['topLinkClicks'] = 0,
       'linkSettings' => get_site_url(null, '/wp-admin/admin.php?page=mailpoet-settings#basics'),
       'linkStats' => get_site_url(null, '/wp-admin/admin.php?page=mailpoet-newsletters#/stats/' . $newsletter->id()),
       'premiumPluginActive' => is_plugin_active('mailpoet-premium/mailpoet-premium.php'),
       'clicked' => $clicked,
       'opened' => $opened,
     ];
+    if($link) {
+      $context['topLinkClicks'] = (int)$link->clicksCount;
+      $context['topLink'] = $link->url;
+    }
+    return $context;
   }
 
   private function markTaskAsFinished(ScheduledTask $task) {

lib/Models/NewsletterLink.php

@@ -7,7 +7,7 @@ class NewsletterLink extends Model {
   public static $_table = MP_NEWSLETTER_LINKS_TABLE;
 
   static function findTopLinkForNewsletter(Newsletter $newsletter) {
-    return self::selectExpr('links.*')
+    $link = self::selectExpr('links.*')
       ->selectExpr('count(*)', 'clicksCount')
       ->tableAlias('links')
       ->innerJoin(StatisticsClicks::$_table,
@@ -18,6 +18,10 @@ class NewsletterLink extends Model {
       ->orderByDesc('clicksCount')
       ->limit(1)
       ->findOne();
+    if(!$link) {
+      return null;
+    }
+    return $link;
   }
 
 }

tests/integration/Cron/Workers/StatsNotifications/WorkerTest.php

@@ -186,4 +186,36 @@ class WorkerTest extends \MailPoetTest {
     $this->stats_notifications->process();
   }
 
+  function testItWorksForNewsletterWithNoStats() {
+    $newsletter = Newsletter::createOrUpdate([
+      'subject' => 'Email Subject2',
+      'type' => Newsletter::TYPE_STANDARD,
+    ]);
+    $sending_task = ScheduledTask::createOrUpdate([
+      'type' => 'sending',
+      'status' => ScheduledTask::STATUS_COMPLETED,
+    ]);
+    $stats_notifications_task = ScheduledTask::createOrUpdate([
+      'type' => Worker::TASK_TYPE,
+      'status' => ScheduledTask::STATUS_SCHEDULED,
+      'scheduled_at' => '2016-01-02 12:13:14',
+      'processed_at' => null,
+    ]);
+    StatsNotification::createOrUpdate([
+      'newsletter_id' => $newsletter->id(),
+      'task_id' => $stats_notifications_task->id(),
+    ]);
+    SendingQueue::createOrUpdate([
+      'newsletter_rendered_subject' => 'Email Subject2',
+      'task_id' => $sending_task->id(),
+      'newsletter_id' => $newsletter->id(),
+      'count_processed' => 15,
+    ]);
+
+    $this->mailer->expects($this->once())
+      ->method('send');
+
+    $this->stats_notifications->process();
+  }
+
 }