Add setup method and Setting object to configure AMS

lib/active_model/serializer.rb

@@ -1,6 +1,7 @@
 require 'active_model/array_serializer'
 require 'active_model/serializable'
 require 'active_model/serializer/associations'
+require 'active_model/serializer/settings'
 
 module ActiveModel
   class Serializer
@@ -12,6 +13,10 @@ module ActiveModel
         base._associations = []
       end
 
+      def setup
+        yield SETTINGS
+      end
+
       def serializer_for(resource)
         if resource.respond_to?(:to_ary)
           ArraySerializer

lib/active_model/serializer/settings.rb

@@ -0,0 +1,27 @@
+module ActiveModel
+  class Serializer
+    class Settings
+      def initialize
+        @data = {}
+      end
+
+      def [](key)
+        @data[key.to_s]
+      end
+
+      def []=(key, value)
+        @data[key.to_s] = value
+      end
+
+      def each(&block)
+        @data.each(&block)
+      end
+
+      def clear
+        @data.clear
+      end
+    end
+
+    SETTINGS = Settings.new
+  end
+end

test/unit/active_model/serializer/settings_test.rb

@@ -0,0 +1,49 @@
+require 'test_helper'
+
+module ActiveModel
+  class Serializer
+    class Settings
+      class Test < ActiveModel::TestCase
+        def test_settings_const_is_an_instance_of_settings
+          assert_kind_of Settings, SETTINGS
+        end
+
+        def test_settings_instance
+          settings = Settings.new
+          settings[:setting1] = 'value1'
+
+          assert_equal 'value1', settings[:setting1]
+        end
+
+        def test_each_settings
+          settings = Settings.new
+          settings['setting1'] = 'value1'
+          settings['setting2'] = 'value2'
+
+          actual = {}
+
+          settings.each do |k, v|
+            actual[k] = v
+          end
+
+          assert_equal({ 'setting1' => 'value1', 'setting2' => 'value2' }, actual)
+
+        end
+      end
+
+      class SetupTest < ActiveModel::TestCase
+        def test_setup
+          ActiveModel::Serializer.setup do |settings|
+            settings[:a] = 'v1'
+            settings[:b] = 'v2'
+          end
+
+          assert_equal 'v1', SETTINGS[:a]
+          assert_equal 'v2', SETTINGS[:b]
+        ensure
+          SETTINGS.clear
+        end
+      end
+    end
+  end
+end