This commit merges most of the work done by Piotr Sarnacki in his Ruby Summer of Code project.

His work brings several capabilities from app to engines, as routes, middleware stack, asset handling and much more. Please check Rails::Engine documentation for more refenrences.

Merge remote branch 'drogus/engines'

1 files changed, 38 insertions, 4 deletions

diff --git a/activemodel/lib/active_model/naming.rb b/activemodel/lib/active_model/naming.rb
index d79635cfb3..dadb1882e4 100644
--- a/activemodel/lib/active_model/naming.rb
+++ b/activemodel/lib/active_model/naming.rb
@@ -2,18 +2,22 @@ require 'active_support/inflector'
 
 module ActiveModel
   class Name < String
-    attr_reader :singular, :plural, :element, :collection, :partial_path
+    attr_reader :singular, :plural, :element, :collection, :partial_path, :route_key, :param_key
     alias_method :cache_key, :collection
 
-    def initialize(klass)
+    def initialize(klass, namespace = nil)
       super(klass.name)
+      @unnamespaced = self.sub(/^#{namespace.name}::/, '') if namespace
+
       @klass = klass
-      @singular = ActiveSupport::Inflector.underscore(self).tr('/', '_').freeze
+      @singular = _singularize(self).freeze
       @plural = ActiveSupport::Inflector.pluralize(@singular).freeze
       @element = ActiveSupport::Inflector.underscore(ActiveSupport::Inflector.demodulize(self)).freeze
       @human = ActiveSupport::Inflector.humanize(@element).freeze
       @collection = ActiveSupport::Inflector.tableize(self).freeze
       @partial_path = "#{@collection}/#{@element}".freeze
+      @param_key = (namespace ? _singularize(@unnamespaced) : @singular).freeze
+      @route_key = (namespace ? ActiveSupport::Inflector.pluralize(@param_key) : @plural).freeze
     end
 
     # Transform the model name into a more humane format, using I18n. By default,
@@ -36,6 +40,11 @@ module ActiveModel
       options.reverse_merge! :scope => [@klass.i18n_scope, :models], :count => 1, :default => defaults
       I18n.translate(defaults.shift, options)
     end
+
+    private
+      def _singularize(str)
+        ActiveSupport::Inflector.underscore(str).tr('/', '_')
+      end
   end
 
   # == Active Model Naming
@@ -58,7 +67,8 @@ module ActiveModel
     # Returns an ActiveModel::Name object for module. It can be
     # used to retrieve all kinds of naming-related information.
     def model_name
-      @_model_name ||= ActiveModel::Name.new(self)
+      namespace = self.parents.detect { |n| n.respond_to?(:_railtie) }
+      @_model_name ||= ActiveModel::Name.new(self, namespace)
     end
 
     # Returns the plural class name of a record or class. Examples:
@@ -85,6 +95,30 @@ module ActiveModel
       plural(record_or_class) == singular(record_or_class)
     end
 
+    # Returns string to use while generating route names. It differs for
+    # namespaced models regarding whether it's inside isolated engine.
+    #
+    # For isolated engine:
+    # ActiveModel::Naming.route_key(Blog::Post) #=> posts
+    #
+    # For shared engine:
+    # ActiveModel::Naming.route_key(Blog::Post) #=> blog_posts
+    def self.route_key(record_or_class)
+      model_name_from_record_or_class(record_or_class).route_key
+    end
+
+    # Returns string to use for params names. It differs for
+    # namespaced models regarding whether it's inside isolated engine.
+    #
+    # For isolated engine:
+    # ActiveModel::Naming.route_key(Blog::Post) #=> post
+    #
+    # For shared engine:
+    # ActiveModel::Naming.route_key(Blog::Post) #=> blog_post
+    def self.param_key(record_or_class)
+      model_name_from_record_or_class(record_or_class).param_key
+    end
+
     private
       def self.model_name_from_record_or_class(record_or_class)
         (record_or_class.is_a?(Class) ? record_or_class : record_or_class.class).model_name