Don't change values in @raw_attributes during serialization

During `init_with`, the attributes given to the coder will be placed
into `@raw_attributes`. As such, we should read from `@raw_attributes`
when encoding, rather than `@attributes`, which has been type cast.

activerecord/lib/active_record/attribute_methods.rb

@@ -289,7 +289,7 @@ module ActiveRecord
 
     # Placeholder so it can be overriden when needed by serialization
     def attributes_for_coder # :nodoc:
-      attributes
+      attributes_before_type_cast
     end
 
     # Returns an <tt>#inspect</tt>-like string for the value of the

activerecord/lib/active_record/attribute_methods/serialization.rb

@@ -138,7 +138,7 @@ module ActiveRecord
             attrs[name] = if self.class.serialized_attributes.include?(name)
                             @raw_attributes[name].serialized_value
                           else
-                            read_attribute(name)
+                            read_attribute_before_type_cast(name)
                           end
           end
         end

activerecord/test/cases/store_test.rb

@@ -183,20 +183,6 @@ class StoreTest < ActiveRecord::TestCase
     assert_equal({}, @john.params)
   end
 
-  test "attributes_for_coder should return stored fields already serialized" do
-    attributes = {
-      "id" => @john.id,
-      "name"=> @john.name,
-      "settings" => "--- !ruby/hash:ActiveSupport::HashWithIndifferentAccess\ncolor: black\n",
-      "preferences" => "--- !ruby/hash:ActiveSupport::HashWithIndifferentAccess\nremember_login: true\n",
-      "json_data" => "{\"height\":\"tall\"}", "json_data_empty"=>"{\"is_a_good_guy\":true}",
-      "params" => "--- !ruby/hash:ActiveSupport::HashWithIndifferentAccess {}\n",
-      "account_id"=> @john.account_id
-    }
-
-    assert_equal attributes, @john.attributes_for_coder
-  end
-
   test "dump, load and dump again a model" do
     dumped = YAML.dump(@john)
     loaded = YAML.load(dumped)

activerecord/test/cases/yaml_serialization_test.rb

@@ -23,13 +23,6 @@ class YamlSerializationTest < ActiveRecord::TestCase
     assert_equal({:omg=>:lol}, YAML.load(YAML.dump(topic)).content)
   end
 
-  def test_encode_with_coder
-    topic = Topic.first
-    coder = {}
-    topic.encode_with coder
-    assert_equal({'attributes' => topic.attributes}, coder)
-  end
-
   def test_psych_roundtrip
     topic = Topic.first
     assert topic
@@ -47,4 +40,16 @@ class YamlSerializationTest < ActiveRecord::TestCase
   def test_active_record_relation_serialization
     [Topic.all].to_yaml
   end
+
+  def test_raw_types_are_not_changed_on_round_trip
+    topic = Topic.new(parent_id: "123")
+    assert_equal "123", topic.parent_id_before_type_cast
+    assert_equal "123", YAML.load(YAML.dump(topic)).parent_id_before_type_cast
+  end
+
+  def test_cast_types_are_not_changed_on_round_trip
+    topic = Topic.new(parent_id: "123")
+    assert_equal 123, topic.parent_id
+    assert_equal 123, YAML.load(YAML.dump(topic)).parent_id
+  end
 end