From c2a5b52767c14cb3c46bf174fda207bac1dda499 Mon Sep 17 00:00:00 2001
From: Mojca Lorber <mlorber@biosistemika.com>
Date: Tue, 14 Nov 2017 15:04:37 +0100
Subject: [PATCH] fix bug when removing all keywords in protocol

---
 app/controllers/protocols_controller.rb | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/app/controllers/protocols_controller.rb b/app/controllers/protocols_controller.rb
index 9116cb4d4..4b944f316 100644
--- a/app/controllers/protocols_controller.rb
+++ b/app/controllers/protocols_controller.rb
@@ -180,8 +180,10 @@ class ProtocolsController < ApplicationController
   def update_keywords
     respond_to do |format|
       # sanitize user input
-      params[:keywords].collect! do |keyword|
-        escape_input(keyword)
+      if params[:keywords]
+        params[:keywords].collect! do |keyword|
+          escape_input(keyword)
+        end
       end
       if @protocol.update_keywords(params[:keywords])
         format.json do