minor #461 Minor refactor to new comment action (yceruto)

This PR was merged into the master branch.

Discussion
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Minor refactor to new comment action

I couldn't find a text where this was explicitly mentioned, but the code above seems unconventional with respect to what the documentation shows and the rest of the application code.

Refs:
* http://symfony.com/doc/current/best_practices/forms.html#building-forms
* http://symfony.com/doc/current/best_practices/forms.html#handling-form-submits
* http://symfony.com/doc/current/forms.html#building-the-form
* http://symfony.com/doc/current/forms.html#handling-form-submissions
* https://github.com/symfony/symfony-demo/blob/master/src/AppBundle/Controller/Admin/BlogController.php#L75-L93

Commits
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5c11bcd Refactor new comment action

Author: javiereguiluz

src/AppBundle/Controller/BlogController.php

@@ -92,16 +92,15 @@ public function postShowAction(Post $post)
      */
     public function commentNewAction(Request $request, Post $post)
     {
-        $form = $this->createForm(CommentType::class);
+        $comment = new Comment();
+        $comment->setAuthor($this->getUser());
+        $comment->setPost($post);
+
+        $form = $this->createForm(CommentType::class, $comment);
 
         $form->handleRequest($request);
 
         if ($form->isSubmitted() && $form->isValid()) {
-            /** @var Comment $comment */
-            $comment = $form->getData();
-            $comment->setAuthor($this->getUser());
-            $comment->setPost($post);
-
             $entityManager = $this->getDoctrine()->getManager();
             $entityManager->persist($comment);
             $entityManager->flush();