Deprecate RAILS_ROOT in favor of Rails.root (which proxies to the application's object root)

Author: Carl Lerche

actionpack/lib/action_controller/metal/helpers.rb

@@ -54,7 +54,7 @@ module Helpers
     included do
       # Set the default directory for helpers
       extlib_inheritable_accessor(:helpers_dir) do
-        defined?(RAILS_ROOT) ? "#{RAILS_ROOT}/app/helpers" : "app/helpers"
+        defined?(Rails) ? "#{Rails.root}/app/helpers" : "app/helpers"
       end
     end
 

activesupport/lib/active_support/testing/isolation.rb

@@ -1,3 +1,5 @@
+require "active_support/core_ext/load_error"
+
 module ActiveSupport
   module Testing
     class ProxyTestResult

railties/bin/rails

@@ -19,6 +19,7 @@ end
 
 ARGV << "--help" if ARGV.empty?
 
+require 'rails'
 require 'rails/generators'
 require 'rails/generators/rails/app/app_generator'
 

railties/builtin/rails_info/rails/info.rb

@@ -75,7 +75,7 @@ def to_html
 
       protected
         def rails_vendor_root
-          @rails_vendor_root ||= "#{RAILS_ROOT}/vendor/rails"
+          @rails_vendor_root ||= "#{Rails.root}/vendor/rails"
         end
 
         def git_info
@@ -124,7 +124,7 @@ def git_info
 
     # The application's location on the filesystem.
     property 'Application root' do
-      File.expand_path(RAILS_ROOT)
+      File.expand_path(Rails.root)
     end
 
     # The current Rails environment (development, test, or production).

railties/guides/source/2_2_release_notes.textile

@@ -51,7 +51,7 @@ If you want to generate these guides locally, inside your application:
 rake doc:guides
 </ruby>
 
-This will put the guides inside +RAILS_ROOT/doc/guides+ and you may start surfing straight away by opening +RAILS_ROOT/doc/guides/index.html+ in your favourite browser.
+This will put the guides inside +Rails.root/doc/guides+ and you may start surfing straight away by opening +Rails.root/doc/guides/index.html+ in your favourite browser.
 
 * Lead Contributors: "Rails Documentation Team":http://guides.rails.info/credits.html
 * Major contributions from "Xavier Noria":http://advogato.org/person/fxn/diary.html and "Hongli Lai":http://izumi.plan99.net/blog/.

railties/guides/source/action_controller_overview.textile

@@ -653,7 +653,7 @@ class ClientsController < ApplicationController
   # Stream a file that has already been generated and stored on disk.
   def download_pdf
     client = Client.find(params[:id])
-    send_data("#{RAILS_ROOT}/files/clients/#{client.id}.pdf",
+    send_data("#{Rails.root}/files/clients/#{client.id}.pdf",
               :filename => "#{client.name}.pdf",
               :type => "application/pdf")
   end

railties/guides/source/command_line.textile

@@ -424,10 +424,10 @@ INFO: For a good rundown on generators, see "Understanding Generators":http://wi
 
 Generators are code that generates code. Let's experiment by building one. Our generator will generate a text file.
 
-The Rails generator by default looks in these places for available generators, where RAILS_ROOT is the root of your Rails application, like /home/foobar/commandsapp:
+The Rails generator by default looks in these places for available generators, where Rails.root is the root of your Rails application, like /home/foobar/commandsapp:
 
-* RAILS_ROOT/lib/generators
-* RAILS_ROOT/vendor/generators
+* Rails.root/lib/generators
+* Rails.root/vendor/generators
 * Inside any plugin with a directory like "generators" or "rails_generators"
 * ~/.rails/generators
 * Inside any Gem you have installed with a name ending in "_generator"
@@ -465,7 +465,7 @@ We take whatever args are supplied, save them to an instance variable, and liter
 
 * Check there's a *public* directory. You bet there is.
 * Run the ERb template called "tutorial.erb".
-* Save it into "RAILS_ROOT/public/tutorial.txt".
+* Save it into "Rails.root/public/tutorial.txt".
 * Pass in the arguments we saved through the +:assign+ parameter.
 
 Next we'll build the template:

railties/lib/rails/backtrace_cleaner.rb

@@ -18,7 +18,7 @@ class BacktraceCleaner < ActiveSupport::BacktraceCleaner
 
     def initialize
       super
-      add_filter   { |line| line.sub("#{RAILS_ROOT}/", '') }
+      add_filter   { |line| line.sub("#{Rails.root}/", '') }
       add_filter   { |line| line.sub(ERB_METHOD_SIG, '') }
       add_filter   { |line| line.sub('./', '/') } # for tests
 
@@ -37,7 +37,7 @@ def add_gem_filters
           add_filter { |line| line.sub(/(#{path})\/gems\/([a-z]+)-([0-9.]+)\/(.*)/, '\2 (\3) \4')}
         end
 
-        vendor_gems_path = Rails::GemDependency.unpacked_path.sub("#{RAILS_ROOT}/",'')
+        vendor_gems_path = Rails::GemDependency.unpacked_path.sub("#{Rails.root}/",'')
         add_filter { |line| line.sub(/(#{vendor_gems_path})\/([a-z]+)-([0-9.]+)\/(.*)/, '\2 (\3) [v] \4')}
       end
   end

railties/lib/rails/commands/about.rb

@@ -1,4 +1,3 @@
-require "#{RAILS_ROOT}/config/application"
 Rails.application.new
 require 'rails/info'
 puts Rails::Info

railties/lib/rails/commands/console.rb

@@ -12,7 +12,7 @@
 end
 
 libs =  " -r irb/completion"
-libs << %( -r "#{RAILS_ROOT}/config/environment")
+libs << %( -r "#{Rails.root}/config/environment")
 libs << " -r rails/console_app"
 libs << " -r rails/console_sandbox" if options[:sandbox]
 libs << " -r rails/console_with_helpers"

railties/lib/rails/commands/dbconsole.rb

@@ -25,7 +25,7 @@
 end
 
 env = ARGV.first || ENV['RAILS_ENV'] || 'development'
-unless config = YAML::load(ERB.new(IO.read(RAILS_ROOT + "/config/database.yml")).result)[env]
+unless config = YAML::load(ERB.new(IO.read(Rails.root + "/config/database.yml")).result)[env]
   abort "No database is configured for the environment '#{env}'"
 end
 

railties/lib/rails/commands/destroy.rb

@@ -1,5 +1,4 @@
 require File.expand_path(File.join(File.dirname(__FILE__), '..', 'generators'))
-require "#{RAILS_ROOT}/config/application"
 
 if ARGV.size == 0
   Rails::Generators.help

railties/lib/rails/commands/server.rb

@@ -7,7 +7,7 @@
   :Port        => 3000,
   :Host        => "0.0.0.0",
   :environment => (ENV['RAILS_ENV'] || "development").dup,
-  :config      => RAILS_ROOT + "/config.ru",
+  :config      => Rails.root + "/config.ru",
   :detach      => false,
   :debugger    => false
 }
@@ -46,7 +46,7 @@
 
 if options[:detach]
   Process.daemon
-  pid = "#{RAILS_ROOT}/tmp/pids/server.pid"
+  pid = "#{Rails.root}/tmp/pids/server.pid"
   File.open(pid, 'w'){ |f| f.write(Process.pid) }
   at_exit { File.delete(pid) if File.exist?(pid) }
 end

railties/lib/rails/configuration.rb

@@ -34,37 +34,25 @@ def after_initialize(&blk)
 
     def root
       @root ||= begin
-        if defined?(RAILS_ROOT)
-          root = RAILS_ROOT
-        else
-          call_stack = caller.map { |p| p.split(':').first }
-          root_path  = call_stack.detect { |p| p !~ %r[railties/lib/rails] }
-          root_path  = File.dirname(root_path)
-
-          while root_path && File.directory?(root_path) && !File.exist?("#{root_path}/config.ru")
-            parent = File.dirname(root_path)
-            root_path = parent != root_path && parent
-          end
-
-          Object.class_eval("RAILS_ROOT = ''")
+        call_stack = caller.map { |p| p.split(':').first }
+        root_path  = call_stack.detect { |p| p !~ %r[railties/lib/rails] }
+        root_path  = File.dirname(root_path)
 
-          root = File.exist?("#{root_path}/config.ru") ? root_path : Dir.pwd
+        while root_path && File.directory?(root_path) && !File.exist?("#{root_path}/config.ru")
+          parent = File.dirname(root_path)
+          root_path = parent != root_path && parent
         end
 
-        root = RUBY_PLATFORM =~ /(:?mswin|mingw)/ ?
-          Pathname.new(root).expand_path.to_s :
-          Pathname.new(root).realpath.to_s
+        root = File.exist?("#{root_path}/config.ru") ? root_path : Dir.pwd
 
-        # TODO: Remove RAILS_ROOT
-        RAILS_ROOT.replace(root)
-        root
+        RUBY_PLATFORM =~ /(:?mswin|mingw)/ ?
+          Pathname.new(root).expand_path :
+          Pathname.new(root).realpath
       end
     end
 
     def root=(root)
-      Object.class_eval("RAILS_ROOT = ''") unless defined?(RAILS_ROOT)
-      RAILS_ROOT.replace(root)
-      @root = root
+      @root = Pathname.new(root).expand_path
     end
 
     def paths

railties/lib/rails/core.rb

@@ -6,7 +6,7 @@ module Rails
   # TODO: w0t?
   class << self
     def application
-      @@application
+      @@application ||= nil
     end
 
     def application=(application)
@@ -43,7 +43,7 @@ def backtrace_cleaner
     end
 
     def root
-      Pathname.new(RAILS_ROOT) if defined?(RAILS_ROOT)
+      application && application.config.root
     end
 
     def env

railties/lib/rails/deprecation.rb

@@ -0,0 +1,17 @@
+require "active_support/string_inquirer"
+require "active_support/deprecation"
+
+RAILS_ROOT = (Class.new(ActiveSupport::Deprecation::DeprecationProxy) do
+  def target
+    Rails.root
+  end
+
+  def replace(val)
+    puts OMG
+  end
+
+  def warn(callstack, called, args)
+    msg = "RAILS_ROOT is deprecated! Use Rails.root instead."
+    ActiveSupport::Deprecation.warn(msg, callstack)
+  end
+end).new

railties/lib/rails/gem_dependency.rb

@@ -11,7 +11,7 @@ class GemDependency < Gem::Dependency
     attr_accessor :lib, :source, :dep
 
     def self.unpacked_path
-      @unpacked_path ||= File.join(RAILS_ROOT, 'vendor', 'gems')
+      @unpacked_path ||= File.join(Rails.root, 'vendor', 'gems')
     end
 
     @@framework_gems = {}

railties/lib/rails/generators.rb

@@ -92,8 +92,8 @@ def self.gems_generators_paths
           generator_path = File.join(spec.full_gem_path, "lib/generators")
           paths << generator_path if File.exist?(generator_path)
         end
-      elsif defined?(RAILS_ROOT)
-        paths += Dir[File.join(RAILS_ROOT, "vendor", "gems", "gems", "*", "lib", "generators")]
+      elsif defined?(Rails.root)
+        paths += Dir[File.join(Rails.root, "vendor", "gems", "gems", "*", "lib", "generators")]
       end
 
       paths
@@ -102,8 +102,8 @@ def self.gems_generators_paths
     # Load paths from plugin.
     #
     def self.plugins_generators_paths
-      return [] unless defined?(RAILS_ROOT)
-      Dir[File.join(RAILS_ROOT, "vendor", "plugins", "*", "lib", "generators")]
+      return [] unless Rails.root
+      Dir[File.join(Rails.root, "vendor", "plugins", "*", "lib", "generators")]
     end
 
     # Hold configured generators fallbacks. If a plugin developer wants a
@@ -143,7 +143,7 @@ def self.no_color!
     def self.load_paths
       @load_paths ||= begin
         paths = []
-        paths << File.join(RAILS_ROOT, "lib", "generators") if defined?(RAILS_ROOT)
+        paths << File.join(Rails.root, "lib", "generators") if Rails.root
         paths << File.join(Thor::Util.user_home, ".rails", "generators")
         paths += self.plugins_generators_paths
         paths += self.gems_generators_paths

railties/lib/rails/generators/base.rb

@@ -203,8 +203,8 @@ def self.inherited(base) #:nodoc:
         super
         base.source_root # Cache source root
 
-        if defined?(RAILS_ROOT) && base.name !~ /Base$/
-          path = File.expand_path(File.join(RAILS_ROOT, 'lib', 'templates'))
+        if Rails.root && base.name !~ /Base$/
+          path = File.expand_path(File.join(Rails.root, 'lib', 'templates'))
           if base.name.include?('::')
             base.source_paths << File.join(path, base.base_name, base.generator_name)
           else

railties/lib/rails/generators/rails/app/templates/config/application.rb

@@ -7,7 +7,7 @@
   # -- all .rb files in that directory are automatically loaded.
 
   # Add additional load paths for your own custom dirs
-  # config.load_paths += %W( #{RAILS_ROOT}/extras )
+  # config.load_paths += %W( #{root}/extras )
 
   # Specify gems that this application depends on and have them installed with rake gems:install
   # config.gem "bj"

railties/lib/rails/generators/rails/app/templates/config/boot.rb

@@ -1,8 +1,6 @@
 # Don't change this file!
 # Configure your app in config/environment.rb and config/environments/*.rb
 
-RAILS_ROOT = "#{File.dirname(__FILE__)}/.." unless defined?(RAILS_ROOT)
-
 module Rails
   # Mark the version of Rails that generated the boot.rb file. This is
   # a temporary solution and will most likely be removed as Rails 3.0
@@ -70,7 +68,6 @@ class VendorBoot < Boot
     def load_initializer
       require "rails"
       install_gem_spec_stubs
-      Rails::GemDependency.add_frozen_gem_path
     end
 
     def install_gem_spec_stubs

railties/lib/rails/initializer.rb

@@ -9,6 +9,7 @@
 require 'rails/paths'
 require 'rails/core'
 require 'rails/configuration'
+require 'rails/deprecation'
 
 RAILS_ENV = (ENV['RAILS_ENV'] || 'development').dup unless defined?(RAILS_ENV)
 

railties/lib/rails/plugin/loader.rb

@@ -147,7 +147,7 @@ def effective_order_of(plugin)
         end
 
         def application_lib_index
-          $LOAD_PATH.index(File.join(RAILS_ROOT, 'lib')) || 0
+          $LOAD_PATH.index(File.join(Rails.root, 'lib')) || 0
         end
 
         def enabled?(plugin)

railties/lib/rails/tasks.rb

@@ -20,5 +20,5 @@
 
 # Load any custom rakefile extensions
 # TODO: Don't hardcode these paths.
-Dir["#{RAILS_ROOT}/vendor/plugins/*/**/tasks/**/*.rake"].sort.each { |ext| load ext }
-Dir["#{RAILS_ROOT}/lib/tasks/**/*.rake"].sort.each { |ext| load ext }
+Dir["#{Rails.root}/vendor/plugins/*/**/tasks/**/*.rake"].sort.each { |ext| load ext }
+Dir["#{Rails.root}/lib/tasks/**/*.rake"].sort.each { |ext| load ext }