From 9919fac6b5f55b919c72629deecb7418cfabff3b Mon Sep 17 00:00:00 2001
From: Neeraj Singh <neerajdotname@gmail.com>
Date: Thu, 27 May 2010 09:26:15 -0400
Subject: [PATCH] Rails 2.3.8: Hash#deep_merge fails for HashWithIndifferentAccess

[#4702 state:resolved]
---
 .../core_ext/hash/indifferent_access.rb            |   16 ++++++++++++++++
 activesupport/test/core_ext/hash_ext_test.rb       |   17 +++++++++++++++++
 2 files changed, 33 insertions(+), 0 deletions(-)

diff --git a/activesupport/lib/active_support/core_ext/hash/indifferent_access.rb b/activesupport/lib/active_support/core_ext/hash/indifferent_access.rb
index 34ba8a0..24c520a 100644
--- a/activesupport/lib/active_support/core_ext/hash/indifferent_access.rb
+++ b/activesupport/lib/active_support/core_ext/hash/indifferent_access.rb
@@ -111,6 +111,22 @@ class HashWithIndifferentAccess < Hash
     Hash.new(default).merge(self)
   end
 
+  def deep_merge(other_hash)
+    dup = self.dup
+    other_hash.each_pair do |key, value| 
+      key = convert_key(key)
+      oldval = dup[key]
+      newval = convert_value(value)
+       
+      oldval = oldval.to_hash if oldval.respond_to?(:to_hash)
+      newval = newval.to_hash if newval.respond_to?(:to_hash)
+
+      merged_value = oldval.kind_of?(Hash) && newval.kind_of?(Hash) ?  oldval.deep_merge(newval) : newval
+      dup.regular_writer(key, merged_value)
+    end
+    dup
+   end
+
   protected
     def convert_key(key)
       key.kind_of?(Symbol) ? key.to_s : key
diff --git a/activesupport/test/core_ext/hash_ext_test.rb b/activesupport/test/core_ext/hash_ext_test.rb
index 44308c3..ca080e6 100644
--- a/activesupport/test/core_ext/hash_ext_test.rb
+++ b/activesupport/test/core_ext/hash_ext_test.rb
@@ -263,6 +263,23 @@ class HashExtTest < Test::Unit::TestCase
     assert_equal expected, hash_1
   end
 
+  def test_deep_merge_on_indifferent_access
+    hash_1 = HashWithIndifferentAccess.new({ :a => "a", :b => "b", :c => { :c1 => "c1", :c2 => "c2", :c3 => { :d1 => "d1" } } })
+    hash_2 = HashWithIndifferentAccess.new({ :a => 1, :c => { :c1 => 2, :c3 => { :d2 => "d2" } } })
+    hash_3 = { :a => 1, :c => { :c1 => 2, :c3 => { :d2 => "d2" } } }
+    expected = { "a" => 1, "b" => "b", "c" => { "c1" => 2, "c2" => "c2", "c3" => { "d1" => "d1", "d2" => "d2" } } }
+
+    assert_equal expected, hash_1.deep_merge(hash_2)
+    assert_equal expected, hash_1.deep_merge(hash_3)
+
+    assert_equal( { :a => "a", :b => "b", :c => { :c1 => "c1", :c2 => "c2", :c3 => { :d1 => "d1" } } }.with_indifferent_access,
+                  hash_1,
+                  'Original hash should not have been changed')
+
+    hash_1.deep_merge!(hash_2)
+    assert_equal expected, hash_1
+  end
+
   def test_reverse_merge
     defaults = { :a => "x", :b => "y", :c => 10 }.freeze
     options  = { :a => 1, :b => 2 }
-- 
1.6.5.2