From 5047dff2bd40982e58fe5fef8aea8d270faa3541 Mon Sep 17 00:00:00 2001
From: Javier Eguiluz <javier.eguiluz@gmail.com>
Date: Tue, 20 Nov 2018 19:38:30 +0100
Subject: [PATCH] Add support for searching by multiple nested associations

---
 src/Search/QueryBuilder.php | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/src/Search/QueryBuilder.php b/src/Search/QueryBuilder.php
index be2fd2c0d1..e0a7852c35 100644
--- a/src/Search/QueryBuilder.php
+++ b/src/Search/QueryBuilder.php
@@ -104,14 +104,21 @@ public function createSearchQueryBuilder(array $entityConfig, $searchQuery, $sor
         foreach ($entityConfig['search']['fields'] as $fieldName => $metadata) {
             $entityName = 'entity';
             if ($this->isDoctrineAssociation($classMetadata, $fieldName)) {
-                list($associatedEntityName, $associatedFieldName) = explode('.', $fieldName);
-                if (!in_array($associatedEntityName, $entitiesAlreadyJoined)) {
-                    $queryBuilder->leftJoin('entity.'.$associatedEntityName, $associatedEntityName);
-                    $entitiesAlreadyJoined[] = $associatedEntityName;
+                // support arbitrarily nested associations (e.g. foo.bar.baz.qux)
+                $associationComponents = explode('.', $fieldName);
+                for ($i = 0; $i < count($associationComponents) - 1; ++$i) {
+                    $associatedEntityName = $associationComponents[$i];
+                    $associatedFieldName = $associationComponents[$i + 1];
+
+                    if (!in_array($associatedEntityName, $entitiesAlreadyJoined)) {
+                        $parentEntityName = 0 === $i ? 'entity' : $associationComponents[$i - 1];
+                        $queryBuilder->leftJoin($parentEntityName.'.'.$associatedEntityName, $associatedEntityName);
+                        $entitiesAlreadyJoined[] = $associatedEntityName;
+                    }
+
+                    $entityName = $associatedEntityName;
+                    $fieldName = $associatedFieldName;
                 }
-
-                $entityName = $associatedEntityName;
-                $fieldName = $associatedFieldName;
             }
 
             $isSmallIntegerField = 'smallint' === $metadata['dataType'];