bug #495 #494 Implements Serializable interface in the User entity (apetitpa)

This PR was squashed before being merged into the master branch (closes #495).

Discussion
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#494 Implements Serializable interface in the User entity

As discussed in #494, implements the `Serializable` interface in the `User` entity.

Commits
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6ef90ad #494 Implements Serializable interface in the User entity

Author: javiereguiluz

src/AppBundle/Entity/User.php

@@ -27,7 +27,7 @@
  * @author Ryan Weaver <weaverryan@gmail.com>
  * @author Javier Eguiluz <javier.eguiluz@gmail.com>
  */
-class User implements UserInterface
+class User implements UserInterface, \Serializable
 {
     /**
      * @var int
@@ -190,4 +190,28 @@ public function eraseCredentials()
         // if you had a plainPassword property, you'd nullify it here
         // $this->plainPassword = null;
     }
+
+    /** @see \Serializable::serialize() */
+    public function serialize()
+    {
+        return serialize([
+            $this->id,
+            $this->username,
+            $this->password,
+            // see section on salt below
+            // $this->salt,
+        ]);
+    }
+
+    /** @see \Serializable::unserialize() */
+    public function unserialize($serialized)
+    {
+        list(
+            $this->id,
+            $this->username,
+            $this->password,
+            // see section on salt below
+            // $this->salt
+        ) = unserialize($serialized);
+    }
 }