Speed up performance in resolvers by adding fallbacks just when required.

actionpack/lib/abstract_controller/rendering.rb

@@ -142,8 +142,8 @@ module AbstractController
 
   private
 
-    # Normalize options, by converting render "foo" to render :template => "prefix/foo"
-    # and render "/foo" to render :file => "/foo".
+    # Normalize options by converting render "foo" to render :action => "foo" and
+    # render "foo/bar" to render :file => "foo/bar".
     def _normalize_args(action=nil, options={})
       case action
       when NilClass
@@ -151,14 +151,8 @@ module AbstractController
         options, action = action, nil
       when String, Symbol
         action = action.to_s
-        case action.index("/")
-        when NilClass
-          options[:action] = action
-        when 0
-          options[:file] = action
-        else
-          options[:template] = action
-        end
+        key = action.include?(?/) ? :file : :action
+        options[key] = action
       else
         options.merge!(:partial => action)
       end

actionpack/lib/action_view/base.rb

@@ -173,48 +173,41 @@ module ActionView #:nodoc:
     module Subclasses
     end
 
-    include Helpers, Rendering, Partials, Layouts, ::ERB::Util
-
-    extend ActiveSupport::Memoizable
-
-    attr_accessor :base_path, :assigns, :template_extension
-    attr_internal :captures
-
-    class << self
-      delegate :erb_trim_mode=, :to => 'ActionView::Template::Handlers::ERB'
-      delegate :logger, :to => 'ActionController::Base', :allow_nil => true
-    end
+    include Helpers, Rendering, Partials, Layouts, ::ERB::Util, Context
+    extend  ActiveSupport::Memoizable
 
     # Specify whether RJS responses should be wrapped in a try/catch block
     # that alert()s the caught exception (and then re-raises it).
     cattr_accessor :debug_rjs
     @@debug_rjs = false
 
-    # :nodoc:
-    def self.xss_safe?
-      true
+    class_attribute :helpers
+    attr_reader :helpers
+
+    class << self
+      delegate :erb_trim_mode=, :to => 'ActionView::Template::Handlers::ERB'
+      delegate :logger, :to => 'ActionController::Base', :allow_nil => true
     end
 
-    attr_internal :request, :layout
+    attr_accessor :base_path, :assigns, :template_extension, :lookup_context
+    attr_internal :captures, :request, :layout, :controller, :template, :config
 
-    def controller_path
-      @controller_path ||= controller && controller.controller_path
-    end
+    delegate :find_template, :template_exists?, :formats, :formats=,
+             :view_paths, :view_paths=, :with_fallbacks, :update_details, :to => :lookup_context
 
     delegate :request_forgery_protection_token, :template, :params, :session, :cookies, :response, :headers,
              :flash, :action_name, :controller_name, :to => :controller
 
     delegate :logger, :to => :controller, :allow_nil => true
 
-    include Context
+    def self.xss_safe? #:nodoc:
+      true
+    end
 
     def self.process_view_paths(value)
       ActionView::PathSet.new(Array(value))
     end
 
-    class_attribute :helpers
-    attr_reader :helpers
-
     def self.for_controller(controller)
       @views ||= {}
 
@@ -260,12 +253,9 @@ module ActionView #:nodoc:
       @lookup_context.formats = formats if formats
     end
 
-    attr_internal :controller, :template, :config
-
-    attr_reader :lookup_context
-
-    delegate :find_template, :template_exists?, :formats, :formats=,
-             :view_paths, :view_paths=, :update_details, :to => :lookup_context
+    def controller_path
+      @controller_path ||= controller && controller.controller_path
+    end
 
     def punctuate_body!(part)
       flush_output_buffer

actionpack/lib/action_view/lookup_context.rb

@@ -6,6 +6,9 @@ module ActionView
   class LookupContext #:nodoc:
     attr_reader :details, :view_paths
 
+    mattr_accessor :fallbacks
+    @@fallbacks = [FileSystemResolver.new(""), FileSystemResolver.new("/")]
+
     class DetailsKey #:nodoc:
       attr_reader :details
       alias :eql? :equal?
@@ -69,6 +72,19 @@ module ActionView
       end
     end
 
+    # Added fallbacks to the view paths. Useful in cases you are rendering a file.
+    def with_fallbacks
+      added_resolvers = 0
+      self.class.fallbacks.each do |resolver|
+        next if view_paths.include?(resolver)
+        view_paths.push(resolver)
+        added_resolvers += 1
+      end
+      yield
+    ensure
+      added_resolvers.times { view_paths.pop }
+    end
+
     def find_template(name, prefix = nil, partial = false)
       @view_paths.find(name, details, prefix, partial || false, details_key)
     end

actionpack/lib/action_view/paths.rb

@@ -33,7 +33,7 @@ module ActionView #:nodoc:
     def typecast!
       each_with_index do |path, i|
         next unless path.is_a?(String)
-        self[i] = FileSystemResolverWithFallback.new(path)
+        self[i] = FileSystemResolver.new(path)
       end
     end
   end

actionpack/lib/action_view/render/layouts.rb

@@ -48,7 +48,8 @@ module ActionView
     # the given name exists across all details before raising the error.
     def _find_layout(layout) #:nodoc:
       begin
-        find_template(layout)
+        layout =~ /^\// ?
+          with_fallbacks { find_template(layout) } : find_template(layout)
       rescue ActionView::MissingTemplate => e
         update_details(:formats => nil) do
           raise unless template_exists?(layout)

actionpack/lib/action_view/render/rendering.rb

@@ -63,7 +63,7 @@ module ActionView
       elsif options.key?(:text)
         Template::Text.new(options[:text], self.formats.try(:first))
       elsif options.key?(:file)
-        find_template(options[:file], options[:_prefix])
+        with_fallbacks { find_template(options[:file], options[:_prefix]) }
       elsif options.key?(:template)
         find_template(options[:template], options[:_prefix])
       end

actionpack/lib/action_view/template/resolver.rb

@@ -4,7 +4,6 @@ require "active_support/core_ext/array/wrap"
 require "action_view/template"
 
 module ActionView
-  # Abstract superclass
   class Resolver
 
     class_inheritable_accessor(:registered_details)
@@ -30,7 +29,7 @@ module ActionView
       find_all(*args).first
     end
 
-    # Normalizes the arguments and passes it on to find_template
+    # Normalizes the arguments and passes it on to find_template.
     def find_all(name, details = {}, prefix = nil, partial = nil)
       details = normalize_details(details)
       name, prefix = normalize_name(name, prefix)
@@ -82,21 +81,20 @@ module ActionView
   end
 
   class PathResolver < Resolver
-
     EXTENSION_ORDER = [:locale, :formats, :handlers]
 
     def to_s
       @path.to_s
     end
-    alias to_path to_s
+    alias :to_path :to_s
+
+  private
 
     def find_templates(name, details, prefix, partial)
       path = build_path(name, details, prefix, partial)
       query(path, EXTENSION_ORDER.map { |ext| details[ext] })
     end
 
-  private
-
     def build_path(name, details, prefix, partial)
       path = ""
       path << "#{prefix}/" unless prefix.empty?
@@ -141,25 +139,10 @@ module ActionView
       super()
       @path = Pathname.new(path).expand_path
     end
-  end
 
-  # TODO: remove hack
-  class FileSystemResolverWithFallback < Resolver
-    def initialize(path)
-      super()
-      @paths = [FileSystemResolver.new(path), FileSystemResolver.new(""), FileSystemResolver.new("/")]
-    end
-
-    def find_templates(*args)
-      @paths.each do |p|
-        template = p.find_templates(*args)
-        return template unless template.empty?
-      end
-      []
-    end
-
-    def to_s
-      @paths.first.to_s
+    def eql?(resolver)
+      self.class.equal?(resolver.class) && to_path == resolver.to_path
     end
+    alias :== :eql?
   end
 end

actionpack/test/template/compiled_templates_test.rb

@@ -44,7 +44,7 @@ class CompiledTemplatesTest < Test::Unit::TestCase
     end
 
     def render_without_cache(*args)
-      path = ActionView::FileSystemResolverWithFallback.new(FIXTURE_LOAD_PATH)
+      path = ActionView::FileSystemResolver.new(FIXTURE_LOAD_PATH)
       view_paths = ActionView::Base.process_view_paths(path)
       ActionView::Base.new(view_paths, {}).render(*args)
     end

actionpack/test/template/render_test.rb

@@ -270,7 +270,7 @@ class CachedViewRenderTest < ActiveSupport::TestCase
   # Ensure view path cache is primed
   def setup
     view_paths = ActionController::Base.view_paths
-    assert_equal ActionView::FileSystemResolverWithFallback, view_paths.first.class
+    assert_equal ActionView::FileSystemResolver, view_paths.first.class
     setup_view(view_paths)
   end
 end
@@ -281,9 +281,9 @@ class LazyViewRenderTest < ActiveSupport::TestCase
   # Test the same thing as above, but make sure the view path
   # is not eager loaded
   def setup
-    path = ActionView::FileSystemResolverWithFallback.new(FIXTURE_LOAD_PATH)
+    path = ActionView::FileSystemResolver.new(FIXTURE_LOAD_PATH)
     view_paths = ActionView::Base.process_view_paths(path)
-    assert_equal ActionView::FileSystemResolverWithFallback, view_paths.first.class
+    assert_equal ActionView::FileSystemResolver.new(FIXTURE_LOAD_PATH), view_paths.first
     setup_view(view_paths)
   end
 end