Replace the placeholder base_hook API with on_load. To specify some code that

should run during framework load do:

ActiveSupport.on_load(:action_controller) do
  # Code run in the context of AC::Base
end

actionmailer/lib/action_mailer/base.rb

@@ -291,7 +291,7 @@ module ActionMailer #:nodoc:
       :parts_order  => [ "text/plain", "text/enriched", "text/html" ]
     }.freeze
 
-    ActionMailer.run_base_hooks(self)
+    ActiveSupport.run_load_hooks(:action_mailer, self)
 
     class << self
 

actionmailer/lib/action_mailer/railtie.rb

@@ -6,18 +6,18 @@ module ActionMailer
     config.action_mailer = ActiveSupport::OrderedOptions.new
 
     initializer "action_mailer.url_for", :before => :load_environment_config do |app|
-      ActionMailer.base_hook { include app.routes.url_helpers }
+      ActiveSupport.on_load(:action_mailer) { include app.routes.url_helpers }
     end
 
     require "action_mailer/railties/log_subscriber"
     log_subscriber :action_mailer, ActionMailer::Railties::LogSubscriber.new
 
     initializer "action_mailer.logger" do
-      ActionMailer.base_hook { self.logger ||= Rails.logger }
+      ActiveSupport.on_load(:action_mailer) { self.logger ||= Rails.logger }
     end
 
     initializer "action_mailer.set_configs" do |app|
-      ActionMailer.base_hook do
+      ActiveSupport.on_load(:action_mailer) do
         app.config.action_mailer.each do |k,v|
           send "#{k}=", v
         end

actionpack/lib/action_controller/base.rb

@@ -64,8 +64,7 @@ module ActionController
       filter
     end
 
-    ActionController.run_base_hooks(self)
-
+    ActiveSupport.run_load_hooks(:action_controller, self)
   end
 end
 

actionpack/lib/action_controller/railtie.rb

@@ -41,7 +41,7 @@ module ActionController
     log_subscriber :action_controller, ActionController::Railties::LogSubscriber.new
 
     initializer "action_controller.logger" do
-      ActionController.base_hook { self.logger ||= Rails.logger }
+      ActiveSupport.on_load(:action_controller) { self.logger ||= Rails.logger }
     end
 
     initializer "action_controller.set_configs" do |app|
@@ -53,23 +53,23 @@ module ActionController
       ac.stylesheets_dir = paths.public.stylesheets.to_a.first
       ac.secret          = app.config.cookie_secret
 
-      ActionController.base_hook do
+      ActiveSupport.on_load(:action_controller) do
         self.config.merge!(ac)
       end
     end
 
     initializer "action_controller.initialize_framework_caches" do
-      ActionController.base_hook { self.cache_store ||= RAILS_CACHE }
+      ActiveSupport.on_load(:action_controller) { self.cache_store ||= RAILS_CACHE }
     end
 
     initializer "action_controller.set_helpers_path" do |app|
-      ActionController.base_hook do
+      ActiveSupport.on_load(:action_controller) do
         self.helpers_path = app.config.paths.app.helpers.to_a
       end
     end
 
     initializer "action_controller.url_helpers" do |app|
-      ActionController.base_hook do
+      ActiveSupport.on_load(:action_controller) do
         extend ::ActionController::Railties::UrlHelpers.with(app.routes)
       end
 

actionpack/lib/action_view/base.rb

@@ -173,7 +173,7 @@ module ActionView #:nodoc:
       delegate :logger, :to => 'ActionController::Base', :allow_nil => true
     end
 
-    ActionView.run_base_hooks(self)
+    ActiveSupport.run_load_hooks(:action_view, self)
 
     attr_accessor :base_path, :assigns, :template_extension, :lookup_context
     attr_internal :captures, :request, :controller, :template, :config

actionpack/lib/action_view/helpers/active_model_helper.rb

@@ -6,7 +6,7 @@ require 'active_support/core_ext/kernel/reporting'
 require 'active_support/core_ext/object/blank'
 
 module ActionView
-  ActionView.base_hook do
+  ActiveSupport.on_load(:action_view) do
     class ActionView::Base
       @@field_error_proc = Proc.new{ |html_tag, instance| "<div class=\"fieldWithErrors\">#{html_tag}</div>".html_safe }
       cattr_accessor :field_error_proc

actionpack/lib/action_view/helpers/form_helper.rb

@@ -1221,7 +1221,7 @@ module ActionView
     end
   end
 
-  ActionView.base_hook do
+  ActiveSupport.on_load(:action_view) do
     class ActionView::Base
       cattr_accessor :default_form_builder
       @@default_form_builder = ::ActionView::Helpers::FormBuilder

actionpack/lib/action_view/railtie.rb

@@ -10,14 +10,14 @@ module ActionView
 
     initializer "action_view.cache_asset_timestamps" do |app|
       unless app.config.cache_classes
-        ActionView.base_hook do
+        ActiveSupport.on_load(:action_view) do
           ActionView::Helpers::AssetTagHelper.cache_asset_timestamps = false
         end
       end
     end
 
     initializer "action_view.set_configs" do |app|
-      ActionView.base_hook do
+      ActiveSupport.on_load(:action_view) do
         app.config.action_view.each do |k,v|
           send "#{k}=", v
         end

activerecord/lib/active_record.rb

@@ -111,10 +111,10 @@ module ActiveRecord
 
   autoload :TestCase
   autoload :TestFixtures, 'active_record/fixtures'
+end
 
-  base_hook do
-    Arel::Table.engine = Arel::Sql::Engine.new(self)
-  end
+ActiveSupport.on_load(:active_record) do
+  Arel::Table.engine = Arel::Sql::Engine.new(self)
 end
 
 I18n.load_path << File.dirname(__FILE__) + '/active_record/locale/en.yml'

activerecord/lib/active_record/base.rb

@@ -2245,4 +2245,4 @@ end
 
 # TODO: Remove this and make it work with LAZY flag
 require 'active_record/connection_adapters/abstract_adapter'
-ActiveRecord.run_base_hooks(ActiveRecord::Base)
+ActiveSupport.run_load_hooks(:active_record, ActiveRecord::Base)

activerecord/lib/active_record/railtie.rb

@@ -23,18 +23,18 @@ module ActiveRecord
     log_subscriber :active_record, ActiveRecord::Railties::LogSubscriber.new
 
     initializer "active_record.initialize_timezone" do
-      ActiveRecord.base_hook do
+      ActiveSupport.on_load(:active_record) do
         self.time_zone_aware_attributes = true
         self.default_timezone = :utc
       end
     end
 
     initializer "active_record.logger" do
-      ActiveRecord.base_hook { self.logger ||= ::Rails.logger }
+      ActiveSupport.on_load(:active_record) { self.logger ||= ::Rails.logger }
     end
 
     initializer "active_record.set_configs" do |app|
-      ActiveRecord.base_hook do
+      ActiveSupport.on_load(:active_record) do
         app.config.active_record.each do |k,v|
           send "#{k}=", v
         end
@@ -44,7 +44,7 @@ module ActiveRecord
     # This sets the database configuration from Configuration#database_configuration
     # and then establishes the connection.
     initializer "active_record.initialize_database" do |app|
-      ActiveRecord.base_hook do
+      ActiveSupport.on_load(:active_record) do
         self.configurations = app.config.database_configuration
         establish_connection
       end
@@ -53,7 +53,7 @@ module ActiveRecord
     # Expose database runtime to controller for logging.
     initializer "active_record.log_runtime" do |app|
       require "active_record/railties/controller_runtime"
-      ActionController.base_hook do
+      ActiveSupport.on_load(:action_controller) do
         include ActiveRecord::Railties::ControllerRuntime
       end
     end
@@ -71,9 +71,9 @@ module ActiveRecord
     end
 
     initializer "active_record.load_observers" do
-      ActiveRecord.base_hook { instantiate_observers }
+      ActiveSupport.on_load(:active_record) { instantiate_observers }
 
-      ActiveRecord.base_hook do
+      ActiveSupport.on_load(:active_record) do
         ActionDispatch::Callbacks.to_prepare(:activerecord_instantiate_observers) do
           ActiveRecord::Base.instantiate_observers
         end
@@ -81,7 +81,7 @@ module ActiveRecord
     end
 
     initializer "active_record.set_dispatch_hooks", :before => :set_clear_dependencies_hook do |app|
-      ActiveRecord.base_hook do
+      ActiveSupport.on_load(:active_record) do
         unless app.config.cache_classes
           ActionDispatch::Callbacks.after do
             ActiveRecord::Base.reset_subclasses

activesupport/lib/active_support/dependencies/autoload.rb

@@ -3,10 +3,6 @@ require "active_support/lazy_load_hooks"
 
 module ActiveSupport
   module Autoload
-    def self.extended(base)
-      base.extend(LazyLoadHooks)
-    end
-
     @@autoloads = {}
     @@under_path = nil
     @@at_path = nil

activesupport/lib/active_support/i18n.rb

@@ -1,3 +1,3 @@
 require 'i18n'
 I18n.load_path << "#{File.dirname(__FILE__)}/locale/en.yml"
-ActiveSupport.run_base_hooks(:i18n)
+ActiveSupport.run_load_hooks(:i18n)

activesupport/lib/active_support/lazy_load_hooks.rb

@@ -1,25 +1,17 @@
 module ActiveSupport
-  module LazyLoadHooks
-    def _setup_base_hooks
-      @base_hooks ||= Hash.new {|h,k| h[k] = [] }
-      @base ||= {}
-    end
+  @load_hooks = Hash.new {|h,k| h[k] = [] }
+  @loaded = {}
 
-    def base_hook(name = nil, &block)
-      _setup_base_hooks
-
-      if base = @base[name]
-        base.instance_eval(&block)
-      else
-        @base_hooks[name] << block
-      end
-    end
-
-    def run_base_hooks(base, name = nil)
-      _setup_base_hooks
-
-      @base_hooks[name].each { |hook| base.instance_eval(&hook) } if @base_hooks
-      @base[name] = base
+  def self.on_load(name, &block)
+    if base = @loaded[name]
+      base.instance_eval(&block)
+    else
+      @load_hooks[name] << block
     end
   end
+
+  def self.run_load_hooks(name, base = Object)
+    @load_hooks[name].each { |hook| base.instance_eval(&hook) }
+    @loaded[name] = base
+  end
 end

activesupport/lib/active_support/railtie.rb

@@ -35,7 +35,7 @@ module I18n
     config.i18n.load_path = []
 
     initializer "i18n.initialize" do
-      ActiveSupport.base_hook(:i18n) do
+      ActiveSupport.on_load(:i18n) do
         I18n.reload!
 
         ActionDispatch::Callbacks.to_prepare do

railties/lib/rails/application/routes_reloader.rb

@@ -27,7 +27,7 @@ module Rails
 
         routes.clear!
         paths.each { |path| load(path) }
-        ActionController.base_hook { routes.finalize! }
+        ActiveSupport.on_load(:action_controller) { routes.finalize! }
 
         nil
       ensure

railties/lib/rails/engine.rb

@@ -180,8 +180,13 @@ module Rails
 
     initializer :add_view_paths do
       views = paths.app.views.to_a
-      ActionController.base_hook { prepend_view_path(views) } if defined?(ActionController)
-      ActionMailer.base_hook { prepend_view_path(views) } if defined?(ActionMailer)
+      ActiveSupport.on_load(:action_controller) do
+        prepend_view_path(views)
+      end
+
+      ActiveSupport.on_load(:action_mailer) do
+        prepend_view_path(views)
+      end
     end
 
     initializer :add_metals do |app|