From dad7f7735132b48b4ccaeff41ddefd1ce71eda2a Mon Sep 17 00:00:00 2001
From: Martijn van Kempen <martijnvankempen@users.noreply.github.com>
Date: Fri, 26 Jan 2018 17:09:38 +0100
Subject: [PATCH] Nullable patterns no longer throw exceptions (#1210)

Nullable patterns no longer throw exceptions
---
 .../Annotations/SymfonyConstraintAnnotationReader.php       | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/ModelDescriber/Annotations/SymfonyConstraintAnnotationReader.php b/ModelDescriber/Annotations/SymfonyConstraintAnnotationReader.php
index fac864d..6ea8d4f 100644
--- a/ModelDescriber/Annotations/SymfonyConstraintAnnotationReader.php
+++ b/ModelDescriber/Annotations/SymfonyConstraintAnnotationReader.php
@@ -104,8 +104,12 @@ class SymfonyConstraintAnnotationReader
     /**
      * Append the pattern from the constraint to the existing pattern.
      */
-    private function appendPattern(Schema $property, string $newPattern)
+    private function appendPattern(Schema $property, $newPattern)
     {
+        if (null === $newPattern) {
+            return;
+        }
+
         if (null !== $property->getPattern()) {
             $property->setPattern(sprintf('%s, %s', $property->getPattern(), $newPattern));
         } else {