First steps into making Plugin < Engine.

4 files changed, 29 insertions, 11 deletions

diff --git a/railties/lib/rails/application.rb b/railties/lib/rails/application.rb
index 8f562350b4..1286d437c7 100644
--- a/railties/lib/rails/application.rb
+++ b/railties/lib/rails/application.rb
@@ -51,6 +51,11 @@ module Rails
       end
     end
 
+    # Application is always reloadable when config.cache_classes is false.
+    def reloadable?(app)
+      true
+    end
+
     def initialize
       environment = config.paths.config.environment.to_a.first
       require environment if environment
diff --git a/railties/lib/rails/application/finisher.rb b/railties/lib/rails/application/finisher.rb
index 4e7fffd0b3..2ac881ac11 100644
--- a/railties/lib/rails/application/finisher.rb
+++ b/railties/lib/rails/application/finisher.rb
@@ -3,6 +3,18 @@ module Rails
     module Finisher
       include Initializable
 
+      initializer :ensure_load_once_paths_as_subset do
+        extra = ActiveSupport::Dependencies.load_once_paths -
+                ActiveSupport::Dependencies.load_paths
+
+        unless extra.empty?
+          abort <<-end_error
+            load_once_paths must be a subset of the load_paths.
+            Extra items in load_once_paths: #{extra * ','}
+          end_error
+        end
+      end
+
       initializer :add_builtin_route do |app|
         if Rails.env.development?
           app.config.action_dispatch.route_files << File.join(RAILTIES_PATH, 'builtin', 'routes.rb')
diff --git a/railties/lib/rails/engine.rb b/railties/lib/rails/engine.rb
index cf6ca7c3f5..b11c1ac73e 100644
--- a/railties/lib/rails/engine.rb
+++ b/railties/lib/rails/engine.rb
@@ -42,6 +42,10 @@ module Rails
 
     delegate :middleware, :paths, :root, :config, :to => :'self.class'
 
+    def reloadable?(app)
+      app.config.reload_plugins
+    end
+
     # Add configured load paths to ruby load paths and remove duplicates.
     initializer :set_load_path do
       config.load_paths.reverse_each do |path|
@@ -52,21 +56,17 @@ module Rails
 
     # Set the paths from which Rails will automatically load source files,
     # and the load_once paths.
-    initializer :set_autoload_paths do
+    initializer :set_autoload_paths do |app|
       ActiveSupport::Dependencies.load_paths.concat(config.load_paths)
-      ActiveSupport::Dependencies.load_once_paths.concat(config.load_once_paths)
-
-      extra = ActiveSupport::Dependencies.load_once_paths -
-              ActiveSupport::Dependencies.load_paths
 
-      unless extra.empty?
-        abort <<-end_error
-          load_once_paths must be a subset of the load_paths.
-          Extra items in load_once_paths: #{extra * ','}
-        end_error
+      if reloadable?(app)
+        ActiveSupport::Dependencies.load_once_paths.concat(config.load_once_paths)
+      else
+        ActiveSupport::Dependencies.load_once_paths.concat(config.load_paths)
       end
 
       # Freeze so future modifications will fail rather than do nothing mysteriously
+      config.load_paths.freeze
       config.load_once_paths.freeze
     end
 
diff --git a/railties/lib/rails/paths.rb b/railties/lib/rails/paths.rb
index d81af3c709..069371aa9c 100644
--- a/railties/lib/rails/paths.rb
+++ b/railties/lib/rails/paths.rb
@@ -73,7 +73,7 @@ module Rails
 
         @load_once  = @options[:load_once]
         @eager_load = @options[:eager_load]
-        @load_path  = @options[:load_path] || @eager_load
+        @load_path  = @options[:load_path] || @eager_load || @load_once
 
         @root.all_paths << self
       end
@@ -98,6 +98,7 @@ module Rails
 
       def load_once!
         @load_once = true
+        @load_path = true
       end
 
       def load_once?