From 3895acd17598520682468ff1aa0994b7cfc1e316 Mon Sep 17 00:00:00 2001
From: Nicolas Grekas <nicolas.grekas@gmail.com>
Date: Sat, 23 Feb 2019 17:20:51 +0100
Subject: [PATCH] fix merge

---
 src/Symfony/Component/Routing/Generator/UrlGenerator.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Symfony/Component/Routing/Generator/UrlGenerator.php b/src/Symfony/Component/Routing/Generator/UrlGenerator.php
index 1871437eae..729d2b0f38 100644
--- a/src/Symfony/Component/Routing/Generator/UrlGenerator.php
+++ b/src/Symfony/Component/Routing/Generator/UrlGenerator.php
@@ -161,8 +161,8 @@ class UrlGenerator implements UrlGeneratorInterface, ConfigurableRequirementsInt
                 $important = $token[5] ?? false;
 
                 if (!$optional || $important || !\array_key_exists($varName, $defaults) || (null !== $mergedParams[$varName] && (string) $mergedParams[$varName] !== (string) $defaults[$varName])) {
-                    // check requirement
-                    if (null !== $this->strictRequirements && !preg_match('#^'.$token[2].'$#'.(empty($token[4]) ? '' : 'u'), $mergedParams[$varName])) {
+                    // check requirement (while ignoring look-around patterns)
+                    if (null !== $this->strictRequirements && !preg_match('#^'.preg_replace('/\(\?(?:=|<=|!|<!)((?:[^()\\\\]+|\\\\.|\((?1)\))*)\)/', '', $token[2]).'$#i'.(empty($token[4]) ? '' : 'u'), $mergedParams[$token[3]])) {
                         if ($this->strictRequirements) {
                             throw new InvalidParameterException(strtr($message, ['{parameter}' => $varName, '{route}' => $name, '{expected}' => $token[2], '{given}' => $mergedParams[$varName]]));
                         }