Fix serializable_hash with xml generation and default :except option

When generating xml with a custom implementation of serializable_hash,
if using the :except option, it was being overriden by the default AR
implementation that attempts to ignore the inheritance column from STI
automatically. So, if you have an implementation like this:

    def serializable_hash(options={})
      super({ except: %w(some_attr) }.merge!(options))
    end

The :except option was correctly being used for :json generation, but
not for :xml, because the options hash already contained the :except
key with the inheritance column, thus overriding the customization.

This commit fixes this problem by removing the :except logic from the
xml serializer, that happened before calling serializable_hash. Since
serializable_hash also does the same check for inheritance column, this
logic was duplicated in both places, thus it's safe to remove it from
xml serializer (see ActiveRecord::Serialization#serializable_hash).

This is an attempt to solve issue #2498, that claims for a
"Single transformation API for both xml and json representations".

1 files changed, 0 insertions, 5 deletions

diff --git a/activerecord/lib/active_record/serializers/xml_serializer.rb b/activerecord/lib/active_record/serializers/xml_serializer.rb
index b833af64fe..834d01a1e8 100644
--- a/activerecord/lib/active_record/serializers/xml_serializer.rb
+++ b/activerecord/lib/active_record/serializers/xml_serializer.rb
@@ -177,11 +177,6 @@ module ActiveRecord #:nodoc:
   end
 
   class XmlSerializer < ActiveModel::Serializers::Xml::Serializer #:nodoc:
-    def initialize(*args)
-      super
-      options[:except] = Array(options[:except]) | Array(@serializable.class.inheritance_column)
-    end
-
     class Attribute < ActiveModel::Serializers::Xml::Serializer::Attribute #:nodoc:
       def compute_type
         klass = @serializable.class