From 5cfceed460ab2cf1cf61dd18d614a6bb8eac308b Mon Sep 17 00:00:00 2001
From: Christian Flothmann <christian.flothmann@sensiolabs.de>
Date: Thu, 22 Feb 2018 10:17:12 +0100
Subject: [PATCH] throw exception if docblock factory does not exist

---
 .../Component/PropertyInfo/Extractor/PhpDocExtractor.php      | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/Symfony/Component/PropertyInfo/Extractor/PhpDocExtractor.php b/src/Symfony/Component/PropertyInfo/Extractor/PhpDocExtractor.php
index 9494333a2e316..8343f0341943b 100644
--- a/src/Symfony/Component/PropertyInfo/Extractor/PhpDocExtractor.php
+++ b/src/Symfony/Component/PropertyInfo/Extractor/PhpDocExtractor.php
@@ -53,6 +53,10 @@ class PhpDocExtractor implements PropertyDescriptionExtractorInterface, Property
      */
     public function __construct(DocBlockFactoryInterface $docBlockFactory = null, array $mutatorPrefixes = null, array $accessorPrefixes = null, array $arrayMutatorPrefixes = null)
     {
+        if (!class_exists(DocBlockFactory::class)) {
+            throw new \RuntimeException(sprintf('Unable to use the "%s" class as the "phpdocumentor/reflection-docblock" package is not installed.', __CLASS__));
+        }
+
         $this->docBlockFactory = $docBlockFactory ?: DocBlockFactory::createInstance();
         $this->contextFactory = new ContextFactory();
         $this->phpDocTypeHelper = new PhpDocTypeHelper();