From aa0d4e12d66b3ee2a1b94f55a435f8177ae20f84 Mon Sep 17 00:00:00 2001
From: Grant Rodgers <grantr@gmail.com>
Date: Wed, 25 Mar 2009 19:55:57 -0700
Subject: [PATCH] OrderedHash#shift should return nil on empty

---
 activesupport/lib/active_support/ordered_hash.rb |    1 +
 activesupport/test/ordered_hash_test.rb          |    5 +++++
 2 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/activesupport/lib/active_support/ordered_hash.rb b/activesupport/lib/active_support/ordered_hash.rb
index fed8094..0928582 100644
--- a/activesupport/lib/active_support/ordered_hash.rb
+++ b/activesupport/lib/active_support/ordered_hash.rb
@@ -78,6 +78,7 @@ module ActiveSupport
       end
 
       def shift
+        return nil if @keys.empty?
         k = @keys.first
         v = delete(k)
         [k, v]
diff --git a/activesupport/test/ordered_hash_test.rb b/activesupport/test/ordered_hash_test.rb
index 7cd8c8a..9826583 100644
--- a/activesupport/test/ordered_hash_test.rb
+++ b/activesupport/test/ordered_hash_test.rb
@@ -147,6 +147,11 @@ class OrderedHashTest < Test::Unit::TestCase
     pair = @ordered_hash.shift
     assert_equal [@keys.first, @values.first], pair
     assert !@ordered_hash.keys.include?(pair.first)
+
+    while !@ordered_hash.empty?
+      @ordered_hash.shift
+    end
+    assert_nil @ordered_hash.shift
   end
   
   def test_keys
-- 
1.6.2