From d8b5a54ee51d25edc6a4557999765edd4a193d33 Mon Sep 17 00:00:00 2001
From: Teoh Han Hui <teohhanhui@gmail.com>
Date: Thu, 18 Feb 2016 21:16:21 +0800
Subject: [PATCH] Handle circular references in ApiParser

Fixes nelmio/NelmioApiDocBundle#678
---
 Nelmio/Parser/ApiParser.php | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/Nelmio/Parser/ApiParser.php b/Nelmio/Parser/ApiParser.php
index cdf95a7ef2a..3c8acfd9c70 100644
--- a/Nelmio/Parser/ApiParser.php
+++ b/Nelmio/Parser/ApiParser.php
@@ -84,11 +84,14 @@ public function parse(array $item)
      * @param ResourceInterface $resource
      * @param string            $entityClass
      * @param string            $io
+     * @param string[]          $visited
      *
      * @return array
      */
-    private function parseClass(ResourceInterface $resource, $entityClass, $io)
+    private function parseClass(ResourceInterface $resource, $entityClass, $io, array $visited = array())
     {
+        $visited[] = $entityClass;
+
         $classMetadata = $this->classMetadataFactory->getMetadataFor(
             $entityClass,
             $resource->getNormalizationGroups(),
@@ -103,7 +106,7 @@ private function parseClass(ResourceInterface $resource, $entityClass, $io)
                 ($attributeMetadata->isReadable() && self::OUT_PREFIX === $io) ||
                 ($attributeMetadata->isWritable() && self::IN_PREFIX === $io)
             ) {
-                $data[$name] = $this->parseAttribute($resource, $attributeMetadata, $io);
+                $data[$name] = $this->parseAttribute($resource, $attributeMetadata, $io, null, $visited);
             }
         }
 
@@ -117,10 +120,11 @@ private function parseClass(ResourceInterface $resource, $entityClass, $io)
      * @param AttributeMetadataInterface $attributeMetadata
      * @param string                     $io
      * @param Type|null                  $type
+     * @param string[]                   $visited
      *
      * @return array
      */
-    private function parseAttribute(ResourceInterface $resource, AttributeMetadataInterface $attributeMetadata, $io, Type $type = null)
+    private function parseAttribute(ResourceInterface $resource, AttributeMetadataInterface $attributeMetadata, $io, Type $type = null, array $visited = array())
     {
         $data = array(
             'dataType' => null,
@@ -144,7 +148,7 @@ private function parseAttribute(ResourceInterface $resource, AttributeMetadataIn
             $data['actualType'] = DataTypes::COLLECTION;
 
             if ($collectionType = $type->getCollectionType()) {
-                $subAttribute = $this->parseAttribute($resource, $attributeMetadata, $io, $collectionType);
+                $subAttribute = $this->parseAttribute($resource, $attributeMetadata, $io, $collectionType, $visited);
                 if (self::IRI === $subAttribute['dataType']) {
                     $data['dataType'] = 'array of IRIs';
                     $data['subType'] = DataTypes::STRING;
@@ -182,7 +186,7 @@ private function parseAttribute(ResourceInterface $resource, AttributeMetadataIn
 
             $data['actualType'] = DataTypes::MODEL;
             $data['subType'] = $class;
-            $data['children'] = $this->parseClass($resource, $class, $io);
+            $data['children'] = in_array($class, $visited) ? [] : $this->parseClass($resource, $class, $io, $visited);
 
             return $data;
         }