Merge branch 'master' into instance_reader

* master: (30 commits)
  Bump tzinfo. 0.3.31 was released on November 6, 2011.
  Fix GH #4909. Dependency on TZInfo move from AR to AS.
  moving ordered hash to normal hash because ruby 1.9.3 hash defaultly ordered one
  Refactored the OrderedHash related stuff
  Replaced OrderedHash usage with Ruby 1.9 Hash
  Replaced OrderedHash with Hash for ruby 1.9 series
  removed unnecessary code
  replacing the orderhash with hash for ruby-1.9
  Clean up some wording.
  Fix typo.
  test title changed corresponding to the test
  replaced active support ordered hash to ruby hash on active resource
  PostgreSQL does not work in the same way of the other adapters
  AR::Relation#pluck: improve to work with joins
  Fix match docs
  Fix attribute_before_type_cast for serialized attributes. Fixes #4837.
  Fix failing request test
  Fixes in AMo README
  Update README to mention lint.
  Trim down Active Model API by removing valid? and errors.full_messages
  ...

5 files changed, 17 insertions, 5 deletions

diff --git a/activerecord/lib/active_record/attribute_methods/serialization.rb b/activerecord/lib/active_record/attribute_methods/serialization.rb
index 1fe5d9de20..9b1bfa1145 100644
--- a/activerecord/lib/active_record/attribute_methods/serialization.rb
+++ b/activerecord/lib/active_record/attribute_methods/serialization.rb
@@ -110,6 +110,14 @@ module ActiveRecord
           super
         end
       end
+
+      def read_attribute_before_type_cast(attr_name)
+        if serialized_attributes.include?(attr_name)
+          super.unserialized_value
+        else
+          super
+        end
+      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/core.rb b/activerecord/lib/active_record/core.rb
index 28f52bd270..c4a4c0ad9a 100644
--- a/activerecord/lib/active_record/core.rb
+++ b/activerecord/lib/active_record/core.rb
@@ -212,6 +212,8 @@ module ActiveRecord
     # The dup method does not preserve the timestamps (created|updated)_(at|on).
     def initialize_dup(other)
       cloned_attributes = other.clone_attributes(:read_attribute_before_type_cast)
+      self.class.initialize_attributes(cloned_attributes)
+
       cloned_attributes.delete(self.class.primary_key)
 
       @attributes = cloned_attributes
@@ -246,7 +248,7 @@ module ActiveRecord
     #   end
     #   coder = {}
     #   Post.new.encode_with(coder)
-    #   coder # => { 'id' => nil, ... }
+    #   coder # => {"attributes" => {"id" => nil, ... }}
     def encode_with(coder)
       coder['attributes'] = attributes
     end
diff --git a/activerecord/lib/active_record/fixtures.rb b/activerecord/lib/active_record/fixtures.rb
index cf315b687c..b82d5b5621 100644
--- a/activerecord/lib/active_record/fixtures.rb
+++ b/activerecord/lib/active_record/fixtures.rb
@@ -3,7 +3,6 @@ require 'yaml'
 require 'zlib'
 require 'active_support/dependencies'
 require 'active_support/core_ext/object/blank'
-require 'active_support/ordered_hash'
 require 'active_record/fixtures/file'
 
 if defined? ActiveRecord
@@ -508,7 +507,7 @@ module ActiveRecord
       @name         = fixture_name
       @class_name   = class_name
 
-      @fixtures     = ActiveSupport::OrderedHash.new
+      @fixtures     = {}
 
       # Should be an AR::Base type class
       if class_name.is_a?(Class)
diff --git a/activerecord/lib/active_record/relation/calculations.rb b/activerecord/lib/active_record/relation/calculations.rb
index 6bf3050af9..50239f7cb2 100644
--- a/activerecord/lib/active_record/relation/calculations.rb
+++ b/activerecord/lib/active_record/relation/calculations.rb
@@ -177,6 +177,9 @@ module ActiveRecord
     #   Person.where(:confirmed => true).limit(5).pluck(:id)
     #
     def pluck(column_name)
+      if column_name.is_a?(Symbol) && column_names.include?(column_name.to_s)
+        column_name = "#{table_name}.#{column_name}"
+      end
       klass.connection.select_all(select(column_name).arel).map! do |attributes|
         klass.type_cast_attribute(attributes.keys.first, klass.initialize_attributes(attributes))
       end
diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index b6d762c2e2..87dd513880 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -206,8 +206,8 @@ module ActiveRecord
     # Any subsequent condition chained to the returned relation will continue
     # generating an empty relation and will not fire any query to the database.
     #
-    # This is useful in scenarios where you need a chainable response to a method
-    # or a scope that could return zero results.
+    # Used in cases where a method or scope could return zero records but the
+    # result needs to be chainable.
     #
     # For example:
     #