Reference scope by same name as serialization scope

By default, the serialization scope uses current_user, and you can
now reference the scope as "current_user" in the serializer. If you
override the scope using "serialization_scope" in your controller,
it will use that method name instead.

test/serialization_scope_name_test.rb

@@ -0,0 +1,67 @@
+require 'test_helper'
+require 'pathname'
+
+class DefaultScopeNameTest < ActionController::TestCase
+  TestUser = Struct.new(:name, :admin)
+
+  class UserSerializer < ActiveModel::Serializer
+    attributes :admin?
+    def admin?
+      current_user.admin
+    end
+  end
+
+  class UserTestController < ActionController::Base
+    protect_from_forgery
+
+    before_filter { request.format = :json }
+
+    def current_user
+      TestUser.new('Pete', false)
+    end
+
+    def render_new_user
+      respond_with TestUser.new('pete', false), :serializer => UserSerializer
+    end
+  end
+
+ tests UserTestController
+
+  def test_default_scope_name
+    get :render_new_user
+    assert_equal '{"user":{"admin":false}}', @response.body
+  end
+end
+
+class SerializationScopeNameTest < ActionController::TestCase
+  TestUser = Struct.new(:name, :admin)
+
+  class AdminUserSerializer < ActiveModel::Serializer
+    attributes :admin?
+    def admin?
+      current_admin.admin
+    end
+  end
+
+  class AdminUserTestController < ActionController::Base
+    protect_from_forgery
+
+    serialization_scope :current_admin
+    before_filter { request.format = :json }
+
+    def current_admin
+      TestUser.new('Bob', true)
+    end
+
+    def render_new_user
+      respond_with TestUser.new('pete', false), :serializer => AdminUserSerializer
+    end
+  end
+
+  tests AdminUserTestController
+
+  def test_override_scope_name_with_controller
+    get :render_new_user
+    assert_equal '{"admin_user":{"admin":true}}', @response.body
+  end
+end

test/serializer_test.rb

@@ -1338,5 +1338,18 @@ class SerializerTest < ActiveModel::TestCase
 
   end
 
+  def test_scope_name_method
+    serializer = Class.new(ActiveModel::Serializer) do
+      def has_permission?
+        current_user.super_user?
+      end
+    end
 
+    user = User.new
+    user.superuser = true
+    post = Post.new(:title => 'Foo')
+
+    a_serializer = serializer.new(post, :scope => user, :scope_name => :current_user)
+    assert a_serializer.has_permission?
+  end
 end