From f049777a000bbbc8f19efe4564da382c06d66732 Mon Sep 17 00:00:00 2001
From: Guillaume DOTT <guillaume.dott@lafourmi-immo.com>
Date: Tue, 10 Sep 2013 14:59:40 +0200
Subject: [PATCH] Remove mutation of argument string

---
 lib/biju/pdu/phone_number.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/biju/pdu/phone_number.rb b/lib/biju/pdu/phone_number.rb
index 8ecdda8..a52a67c 100644
--- a/lib/biju/pdu/phone_number.rb
+++ b/lib/biju/pdu/phone_number.rb
@@ -4,7 +4,7 @@ module Biju
       attr_accessor :type_of_address, :number
 
       def self.encode(number, type_of_address: :international)
-        number << 'F' if number.length.odd?
+        number = number + 'F' if number.length.odd?
         new(
           number.scan(/../).map(&:reverse).join,
           type_of_address: type_of_address