From b8987e1bdec3299f41809ec6f1d968a67e0fe903 Mon Sep 17 00:00:00 2001
From: Jordi Boggiano <j.boggiano@seld.be>
Date: Tue, 9 Nov 2010 15:49:22 +0100
Subject: [PATCH] [DoctrineBundle] Form transformers shouldn't explode if
 they're passed null as a value

---
 .../Form/ValueTransformer/CollectionToStringTransformer.php   | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/Symfony/Bundle/DoctrineBundle/Form/ValueTransformer/CollectionToStringTransformer.php b/src/Symfony/Bundle/DoctrineBundle/Form/ValueTransformer/CollectionToStringTransformer.php
index c284a28918..ed97255505 100644
--- a/src/Symfony/Bundle/DoctrineBundle/Form/ValueTransformer/CollectionToStringTransformer.php
+++ b/src/Symfony/Bundle/DoctrineBundle/Form/ValueTransformer/CollectionToStringTransformer.php
@@ -138,6 +138,10 @@ class CollectionToStringTransformer extends BaseValueTransformer
      */
     public function transform($value)
     {
+        if (null === $value) {
+            return '';
+        }
+
         $values = array();
         $em = $this->getOption('em');
         $reflField = $em->getClassMetadata($this->getOption('class_name'))