Attachments to Doctrine Jira Issue DDC-1757 - https://github.com/doctrine/doctrine2/issues/2407

11176_DDC1757Test.php

<?php

namespace Doctrine\Tests\ORM\Functional\Ticket;

use Doctrine\ORM\UnitOfWork;

require_once __DIR__ . '/../../../TestInit.php';

class DDC1757Test extends \PHPUnit_Framework_TestCase
{
    protected function setUp()
    {
        parent::setUp();
		
        try {
            $this->_schemaTool->createSchema(array(
                $this->_em->getClassMetadata(__NAMESPACE__ . '\DDC1757A'),
                $this->_em->getClassMetadata(__NAMESPACE__ . '\DDC1757B'),
                $this->_em->getClassMetadata(__NAMESPACE__ . '\DDC1757C'),
                $this->_em->getClassMetadata(__NAMESPACE__ . '\DDC1757D'),
            ));
        } catch(\Exception $ignored) {}
    }

    public function testFailingCase()
    {
		$qb = $this->_em->createQueryBuilder();
		/* @var $qb \Doctrine\ORM\QueryBuilder */
		
		$qb->select('_a')
				->from(__NAMESPACE__ . '\DDC1757A', '_a')
				->from(__NAMESPACE__ . '\DDC1757B', '_b')
				->join('_b.c', '_c')
				->join('_c.d', '_d');
		
		$q = $qb->getQuery();
		$dql = $q->getDQL();
		$q->getResult();
    }
}

/**
 * @Entity
 */
class DDC1757A
{
    /**
     * @Column(type="integer")
     * @Id
	 * @GeneratedValue(strategy="AUTO")
     */
    private $id;
}

/**
 * @Entity
 */
class DDC1757B
{
    /**
     * @Column(type="integer")
     * @Id
	 * @GeneratedValue(strategy="AUTO")
     */
    private $id;

    /**
     * @OneToOne(targetEntity="DDC1757C")
     */
    private $c;
}

/**
 * @Entity
 */
class DDC1757C
{
    /**
     * @Column(type="integer")
     * @Id
     * @GeneratedValue(strategy="AUTO")
     */
    public $id;

     /**
     * @OneToOne(targetEntity="DDC1757D")
     */
    private $d;
}

/**
 * @Entity
 */
class DDC1757D
{
    /**
     * @Column(type="integer")
     * @Id
     * @GeneratedValue(strategy="AUTO")
     */
    public $id;
}

11177_patch-1757.patch

diff --git a/src/lib/Doctrine/ORM/QueryBuilder.php b/src/lib/Doctrine/ORM/QueryBuilder.php
index 5212634..343dcd7 100644
--- a/src/lib/Doctrine/ORM/QueryBuilder.php
+++ b/src/lib/Doctrine/ORM/QueryBuilder.php
@@ -97,6 +97,12 @@ class QueryBuilder
     private $_maxResults = null;
 
     /**
+     * Keeps root entity alias names for join entities
+     * @var array
+     */
+    private $joinRootAliases = array();
+
+    /**
      * Initializes a new <tt>QueryBuilder</tt> that uses the given <tt>EntityManager</tt>.
      *
      * @param EntityManager $em The EntityManager to use.
@@ -234,10 +240,22 @@ class QueryBuilder
      * @deprecated Please use $qb->getRootAliases() instead.
      * @return string $rootAlias
      */
-    public function getRootAlias()
+    public function getRootAlias($rootAlias = null, $alias = null)
     {
-        $aliases = $this->getRootAliases();
-        return $aliases[0];
+        if ( ! is_null($rootAlias) && in_array($rootAlias, $this->getRootAliases())) {
+            // Do nothing
+        } elseif ( ! is_null($rootAlias) && isset($this->joinRootAliases[$rootAlias])) {
+            $rootAlias = $this->joinRootAliases[$rootAlias];
+        } else {
+            $aliases = $this->getRootAliases();
+            $rootAlias = $aliases[0];
+        }
+
+        if ( ! is_null($alias)) {
+            $this->joinRootAliases[$alias] = $rootAlias;
+        }
+
+        return $rootAlias;
     }
 
     /**
@@ -672,9 +690,7 @@ class QueryBuilder
     {
         $rootAlias = substr($join, 0, strpos($join, '.'));
 
-        if ( ! in_array($rootAlias, $this->getRootAliases())) {
-            $rootAlias = $this->getRootAlias();
-        }
+        $rootAlias = $this->getRootAlias($rootAlias, $alias);
 
         $join = new Expr\Join(
             Expr\Join::INNER_JOIN, $join, $alias, $conditionType, $condition, $indexBy
@@ -708,9 +724,7 @@ class QueryBuilder
     {
         $rootAlias = substr($join, 0, strpos($join, '.'));
 
-        if ( ! in_array($rootAlias, $this->getRootAliases())) {
-            $rootAlias = $this->getRootAlias();
-        }
+        $rootAlias = $this->getRootAlias($rootAlias, $alias);
 
         $join = new Expr\Join(
             Expr\Join::LEFT_JOIN, $join, $alias, $conditionType, $condition, $indexBy