feature #10005 [Security] Added named encoders to EncoderFactory (tamirvs)

This PR was squashed before being merged into the 2.5-dev branch (closes #10005).

Discussion
----------

[Security] Added named encoders to EncoderFactory

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #9743
| License       | MIT
| Doc PR        | -

This PR is basically merging FOSAdvancedEncoder. I think it's better than having a separate bundle that most of it's code is a copy of the core.
A use case is: having a different encoders or bcrypt cost based on the user's roles.

Commits
-------

c69e2ca [Security] Added named encoders to EncoderFactory

2 files changed, 48 insertions, 7 deletions

diff --git a/Core/Encoder/EncoderAwareInterface.php b/Core/Encoder/EncoderAwareInterface.php
new file mode 100644
index 0000000..22ae820
--- /dev/null
+++ b/Core/Encoder/EncoderAwareInterface.php
@@ -0,0 +1,28 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Security\Core\Encoder;
+
+/**
+ * @author Christophe Coevoet <stof@notk.org>
+ */
+interface EncoderAwareInterface
+{
+    /**
+     * Gets the name of the encoder used to encode the password.
+     *
+     * If the method returns null, the standard way to retrieve the encoder
+     * will be used instead.
+     *
+     * @return string
+     */
+    public function getEncoderName();
+}
diff --git a/Core/Encoder/EncoderFactory.php b/Core/Encoder/EncoderFactory.php
index 8bad61f..bb5ba91 100644
--- a/Core/Encoder/EncoderFactory.php
+++ b/Core/Encoder/EncoderFactory.php
@@ -30,19 +30,32 @@ class EncoderFactory implements EncoderFactoryInterface
      */
     public function getEncoder($user)
     {
-        foreach ($this->encoders as $class => $encoder) {
-            if ((is_object($user) && !$user instanceof $class) || (!is_object($user) && !is_subclass_of($user, $class) && $user != $class)) {
-                continue;
+        $encoderKey = null;
+
+        if ($user instanceof EncoderAwareInterface && (null !== $encoderName = $user->getEncoderName())) {
+            if (!array_key_exists($encoderName, $this->encoders)) {
+                throw new \RuntimeException(sprintf('The encoder "%s" was not configured.', $encoderName));
             }
 
-            if (!$encoder instanceof PasswordEncoderInterface) {
-                return $this->encoders[$class] = $this->createEncoder($encoder);
+            $encoderKey = $encoderName;
+        } else {
+            foreach ($this->encoders as $class => $encoder) {
+                if ((is_object($user) && $user instanceof $class) || (!is_object($user) && (is_subclass_of($user, $class) || $user == $class))) {
+                    $encoderKey = $class;
+                    break;
+                }
             }
+        }
+
+        if (null === $encoderKey) {
+            throw new \RuntimeException(sprintf('No encoder has been configured for account "%s".', is_object($user) ? get_class($user) : $user));
+        }
 
-            return $this->encoders[$class];
+        if (!$this->encoders[$encoderKey] instanceof PasswordEncoderInterface) {
+            $this->encoders[$encoderKey] = $this->createEncoder($this->encoders[$encoderKey]);
         }
 
-        throw new \RuntimeException(sprintf('No encoder has been configured for account "%s".', is_object($user) ? get_class($user) : $user));
+        return $this->encoders[$encoderKey];
     }
 
     /**