From 91dcfec6f49c5c0426692f2ed73ca3cc98ef4fd5 Mon Sep 17 00:00:00 2001
From: Coleman Watts <coleman@civicrm.org>
Date: Sat, 26 Dec 2015 20:18:22 -0500
Subject: [PATCH] Fix javascript error (cannot join null)

---
 templates/CRM/Event/Form/Participant.tpl | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/templates/CRM/Event/Form/Participant.tpl b/templates/CRM/Event/Form/Participant.tpl
index dbba237f4e..c37ce5f658 100644
--- a/templates/CRM/Event/Form/Participant.tpl
+++ b/templates/CRM/Event/Form/Participant.tpl
@@ -374,8 +374,8 @@
         });
 
         function buildRoleCustomData() {
-          var roleId = $('select[name^=role_id]', $form).val().join();
-          CRM.buildCustomData('Participant', roleId, {/literal}{$roleCustomDataTypeID}{literal});
+          var roleId = $('select[name^=role_id]', $form).val() || [];
+          CRM.buildCustomData('Participant', roleId.join(), {/literal}{$roleCustomDataTypeID}{literal});
         }
 
         //build fee block
-- 
2.25.1