Allow to pass options to associations

Closes #331

lib/active_model/serializer.rb

@@ -107,7 +107,7 @@ end
       @root     = options.fetch(:root, self.class._root)
       @meta_key = options[:meta_key] || :meta
       @meta     = options[@meta_key]
-      @options  = options.reject{|k,v| [:scope, :root, :meta_key, :meta].include?(k) }
+      @options  = options.reject{|k,v| [:root, :meta_key, :meta].include?(k) }
     end
     attr_accessor :object, :scope, :meta_key, :meta, :root, :options
 
@@ -166,7 +166,7 @@ end
 
     def build_serializer(association)
       object = send(association.name)
-      association.build_serializer(object, scope: scope)
+      association.build_serializer(object, options)
     end
 
     def serialize(association)

test/fixtures/poro.rb

@@ -50,6 +50,11 @@ class ProfileSerializer < ActiveModel::Serializer
     scope ? "#{description} - #{scope}" : description
   end
 
+  def name
+    name = object.read_attribute_for_serialization(:name)
+    options[:custom_name] ? "#{name} - #{options[:custom_name]}" : name
+  end
+
   attributes :name, :description
 end
 

test/unit/active_model/serializer/has_one_test.rb

@@ -62,6 +62,15 @@ module ActiveModel
         }, @user_serializer.as_json)
       end
 
+      def test_allow_to_pass_options_to_associations
+        @user_serializer.options.merge!(custom_name: 'custom')
+        @association.embed = :objects
+
+        assert_equal({
+          'user' => { name: 'Name 1', email: 'mail@server.com', profile: { name: 'N1 - custom', description: 'D1' } }
+        }, @user_serializer.as_json)
+      end
+
       def test_associations_embedding_nil_ids_serialization_using_as_json
         @association.embed = :ids
         @user.instance_eval do