From e9552a5f60bd78cfae26849458c89d2f1747e2be Mon Sep 17 00:00:00 2001
From: Sven Fuchs <me@svenfuchs.com>
Date: Mon, 28 Oct 2013 17:09:09 +0100
Subject: [PATCH] can channel be undefined?

---
 assets/scripts/app/pusher.coffee | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/assets/scripts/app/pusher.coffee b/assets/scripts/app/pusher.coffee
index 459c690d..4a86bb68 100644
--- a/assets/scripts/app/pusher.coffee
+++ b/assets/scripts/app/pusher.coffee
@@ -27,18 +27,20 @@ $.extend Travis.Pusher.prototype,
     @subscribe(channel) for channel in channels
 
   subscribe: (channel) ->
+    return unless channel
     channel = @prefix(channel)
     console.log("subscribing to #{channel}")
     unless @pusher?.channel(channel)
       @pusher.subscribe(channel).bind_all((event, data) => @receive(event, data))
 
   unsubscribe: (channel) ->
+    return unless channel
     channel = @prefix(channel)
     console.log("unsubscribing from #{channel}")
     @pusher.unsubscribe(channel) if @pusher?.channel(channel)
 
   prefix: (channel) ->
-    "#{Travis.Pusher.CHANNEL_PREFIX}#{channel}" unless channel.indexOf(Travis.Pusher.CHANNEL_PREFIX) == 0
+    "#{Travis.Pusher.CHANNEL_PREFIX}#{channel}" if channel && channel.indexOf(Travis.Pusher.CHANNEL_PREFIX) != 0
 
   # process pusher messages in batches every 5 minutes when the page is hidden
   processingIntervalWhenHidden: 1000 * 60 * 5