Modified Hydrators to be per-query instances instead of a singleton-like approach.

lib/Doctrine/ORM/AbstractQuery.php

@@ -799,7 +799,7 @@ abstract class AbstractQuery
             return $stmt;
         }
 
-        $data = $this->_em->getHydrator($this->_hydrationMode)->hydrateAll(
+        $data = $this->_em->newHydrator($this->_hydrationMode)->hydrateAll(
             $stmt, $this->_resultSetMapping, $this->_hints
         );
 

lib/Doctrine/ORM/Decorator/EntityManagerDecorator.php

@@ -221,14 +221,6 @@ abstract class EntityManagerDecorator extends ObjectManagerDecorator implements
         return $this->wrapped->getUnitOfWork();
     }
 
-    /**
-     * {@inheritdoc}
-     */
-    public function getHydrator($hydrationMode)
-    {
-        return $this->wrapped->getHydrator($hydrationMode);
-    }
-
     /**
      * {@inheritdoc}
      */

lib/Doctrine/ORM/EntityManager.php

@@ -99,13 +99,6 @@ use Doctrine\Common\Util\ClassUtils;
      */
     private $eventManager;
 
-    /**
-     * The maintained (cached) hydrators. One instance per type.
-     *
-     * @var array
-     */
-    private $hydrators = array();
-
     /**
      * The proxy factory used to create dynamic proxies.
      *
@@ -834,25 +827,6 @@ use Doctrine\Common\Util\ClassUtils;
         return $this->unitOfWork;
     }
 
-    /**
-     * Gets a hydrator for the given hydration mode.
-     *
-     * This method caches the hydrator instances which is used for all queries that don't
-     * selectively iterate over the result.
-     *
-     * @param int $hydrationMode
-     *
-     * @return \Doctrine\ORM\Internal\Hydration\AbstractHydrator
-     */
-    public function getHydrator($hydrationMode)
-    {
-        if ( ! isset($this->hydrators[$hydrationMode])) {
-            $this->hydrators[$hydrationMode] = $this->newHydrator($hydrationMode);
-        }
-
-        return $this->hydrators[$hydrationMode];
-    }
-
     /**
      * Create a new instance for the given hydration mode.
      *

lib/Doctrine/ORM/EntityManagerInterface.php

@@ -51,7 +51,6 @@ interface EntityManagerInterface extends ObjectManager
     public function getConfiguration();
     public function isOpen();
     public function getUnitOfWork();
-    public function getHydrator($hydrationMode);
     public function newHydrator($hydrationMode);
     public function getProxyFactory();
     public function getFilters();