From ce41993a1b9cfbda057b64393d41ae9675a9c1d8 Mon Sep 17 00:00:00 2001
From: Nick Thomas <nick@lupine.me.uk>
Date: Sun, 13 Nov 2011 19:48:18 +0000
Subject: [PATCH] Avoid a backtrace when we try to create a ParserError without
 an upstream error

---
 lib/qmp_client/messages.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/qmp_client/messages.rb b/lib/qmp_client/messages.rb
index ec59e21..2d7279f 100644
--- a/lib/qmp_client/messages.rb
+++ b/lib/qmp_client/messages.rb
@@ -17,7 +17,7 @@ module QMPClient
     # Raised when we're trying to convert raw text into a message, but failing
     class ParserError < StandardError
       attr_reader :upstream_error
-      def initialize(message, upstream)
+      def initialize(message, upstream = nil)
         super(message)
         @upstream_error = upstream
       end