3 files changed, 45 insertions, 22 deletions

diff --git a/actionpack/lib/sprockets/assets.rake b/actionpack/lib/sprockets/assets.rake
index 01132d218f..acf2f256c2 100644
--- a/actionpack/lib/sprockets/assets.rake
+++ b/actionpack/lib/sprockets/assets.rake
@@ -1,24 +1,32 @@
 namespace :assets do
-  task :ensure_env do
-    ENV["RAILS_GROUPS"] ||= "assets"
-    ENV["RAILS_ENV"]    ||= "production"
-  end
-
   desc "Compile all the assets named in config.assets.precompile"
-  task :precompile => :ensure_env do
-    Rake::Task["environment"].invoke
-    Sprockets::Helpers::RailsHelper
+  task :precompile do
+    # We need to do this dance because RAILS_GROUPS is used
+    # too early in the boot process and changing here is already too late.
+    if ENV["RAILS_GROUPS"].to_s.empty? || ENV["RAILS_ENV"].to_s.empty?
+      ENV["RAILS_GROUPS"] ||= "assets"
+      ENV["RAILS_ENV"]    ||= "production"
+      Kernel.exec $0, *ARGV
+    else
+      Rake::Task["environment"].invoke
+
+      # Ensure that action view is loaded and the appropriate sprockets hooks get executed
+      ActionView::Base
+
+      # Always perform caching so that asset_path appends the timestamps to file references.
+      Rails.application.config.action_controller.perform_caching = true
 
-    assets = Rails.application.config.assets.precompile
-    # Always perform caching so that asset_path appends the timestamps to file references.
-    Rails.application.config.action_controller.perform_caching = true
-    Rails.application.assets.precompile(*assets)
+      config = Rails.application.config
+      assets = config.assets.precompile.dup
+      assets << {:to => File.join(Rails.public_path, config.assets.prefix)}
+      Rails.application.assets.precompile(*assets)
+    end
   end
 
   desc "Remove compiled assets"
   task :clean => [:environment, 'tmp:cache:clear'] do
-    assets = Rails.application.config.assets
-    public_asset_path = Rails.public_path + assets.prefix
+    config = Rails.application.config
+    public_asset_path = File.join(Rails.public_path, config.assets.prefix)
     rm_rf public_asset_path, :secure => true
   end
 end
diff --git a/actionpack/lib/sprockets/helpers/rails_helper.rb b/actionpack/lib/sprockets/helpers/rails_helper.rb
index ec3d36d5ad..c239af77bc 100644
--- a/actionpack/lib/sprockets/helpers/rails_helper.rb
+++ b/actionpack/lib/sprockets/helpers/rails_helper.rb
@@ -70,8 +70,8 @@ module Sprockets
 
     private
       def debug_assets?
-        params[:debug_assets] == '1' ||
-          params[:debug_assets] == 'true'
+        Rails.env.development? || Rails.env.test? ||
+          params[:debug_assets] == '1' || params[:debug_assets] == 'true'
       rescue NoMethodError
         false
       end
@@ -112,11 +112,22 @@ module Sprockets
           asset_environment[source]
         end
 
+        def digest_for(logical_path)
+          if asset = asset_environment[logical_path]
+            return asset.digest_path
+          end
+
+          logical_path
+        end
+
         def rewrite_asset_path(source, dir)
           if source[0] == ?/
             source
           else
-            asset_environment.path(source, performing_caching?, dir)
+            source = digest_for(source) if performing_caching?
+            source = File.join(dir, source)
+            source = "/#{source}" unless source =~ /^\//
+            source
           end
         end
 
@@ -128,9 +139,14 @@ module Sprockets
           end
         end
 
-        # When included in Sprockets::Context, we need to ask the top-level config as the controller is not available
         def performing_caching?
-          config.action_controller.present? ? config.action_controller.perform_caching : config.perform_caching
+          # When included in Sprockets::Context, we need to ask the
+          # top-level config as the controller is not available.
+          if config.action_controller.present?
+            config.action_controller.perform_caching
+          else
+            config.perform_caching
+          end
         end
       end
     end
diff --git a/actionpack/lib/sprockets/railtie.rb b/actionpack/lib/sprockets/railtie.rb
index 0a2c8c1ea3..c21bf57935 100644
--- a/actionpack/lib/sprockets/railtie.rb
+++ b/actionpack/lib/sprockets/railtie.rb
@@ -18,9 +18,8 @@ module Sprockets
       require 'sprockets'
 
       app.assets = Sprockets::Environment.new(app.root.to_s) do |env|
-        env.static_root = File.join(app.root.join('public'), config.assets.prefix)
-        env.logger = ::Rails.logger
-        env.version = ::Rails.env + "#{'-' + config.assets.version if config.assets.version.present?}"
+        env.logger  = ::Rails.logger
+        env.version = ::Rails.env + "-#{config.assets.version}"
 
         if config.assets.cache_store != false
           env.cache = ActiveSupport::Cache.lookup_store(config.assets.cache_store) || ::Rails.cache