Moved interpolations out of attachment

lib/paperclip.rb

@@ -32,6 +32,7 @@ require 'paperclip/geometry'
 require 'paperclip/processor'
 require 'paperclip/thumbnail'
 require 'paperclip/storage'
+require 'paperclip/interpolations'
 require 'paperclip/attachment'
 if defined? RAILS_ROOT
   Dir.glob(File.join(File.expand_path(RAILS_ROOT), "lib", "paperclip_processors", "*.rb")).each do |processor|

lib/paperclip/attachment.rb

@@ -198,26 +198,7 @@ module Paperclip
     # style as arguments. This hash can be added to with your own proc if
     # necessary.
     def self.interpolations
-      @interpolations ||= {
-        :rails_root   => lambda{|attachment,style| RAILS_ROOT },
-        :rails_env    => lambda{|attachment,style| RAILS_ENV },
-        :class        => lambda do |attachment,style|
-                           attachment.instance.class.name.underscore.pluralize
-                         end,
-        :basename     => lambda do |attachment,style|
-                           attachment.original_filename.gsub(/#{File.extname(attachment.original_filename)}$/, "")
-                         end,
-        :extension    => lambda do |attachment,style| 
-                           ((style = attachment.styles[style]) && style[:format]) ||
-                           File.extname(attachment.original_filename).gsub(/^\.+/, "")
-                         end,
-        :id           => lambda{|attachment,style| attachment.instance.id },
-        :id_partition => lambda do |attachment, style|
-                           ("%09d" % attachment.instance.id).scan(/\d{3}/).join("/")
-                         end,
-        :attachment   => lambda{|attachment,style| attachment.name.to_s.downcase.pluralize },
-        :style        => lambda{|attachment,style| style || attachment.default_style },
-      }
+      Paperclip::Interpolations
     end
 
     # This method really shouldn't be called that often. It's expected use is
@@ -373,11 +354,10 @@ module Paperclip
     end
 
     def interpolate pattern, style = default_style #:nodoc:
-      interpolations = self.class.interpolations.sort{|a,b| a.first.to_s <=> b.first.to_s }
-      interpolations.reverse.inject( pattern.dup ) do |result, interpolation|
-        tag, blk = interpolation
+      interpolations = Paperclip::Interpolations.all
+      interpolations.reverse.inject( pattern.dup ) do |result, tag|
         result.gsub(/:#{tag}/) do |match|
-          blk.call( self, style )
+          Paperclip::Interpolations.send( tag, self, style )
         end
       end
     end

lib/paperclip/interpolations.rb

+module Paperclip
+  module Interpolations
+    def self.[]= name, block
+      (class << self; self; end).class_eval do
+        define_method(name, &block)
+      end
+    end
+
+    def self.[] name
+      method(name)
+    end
+
+    def self.all
+      (singleton_methods - ["[]=", "[]", "all"]).sort
+    end
+
+    def self.rails_root attachment, style
+      RAILS_ROOT
+    end
+
+    def self.rails_env attachment, style
+      RAILS_ENV
+    end
+
+    def self.class attachment, style
+      attachment.instance.class.to_s.underscore.pluralize
+    end
+
+    def self.basename attachment, style
+      attachment.original_filename.gsub(/#{File.extname(attachment.original_filename)}$/, "")
+    end
+
+    def self.extension attachment, style 
+      ((style = attachment.styles[style]) && style[:format]) ||
+        File.extname(attachment.original_filename).gsub(/^\.+/, "")
+    end
+
+    def self.id attachment, style
+      attachment.instance.id
+    end
+
+    def self.id_partition attachment, style
+      ("%09d" % attachment.instance.id).scan(/\d{3}/).join("/")
+    end
+
+    def self.attachment attachment, style
+      attachment.name.to_s.downcase.pluralize
+    end
+
+    def self.style attachment, style
+      style || attachment.default_style
+    end
+  end
+end

test/helper.rb

@@ -17,6 +17,7 @@ end
 
 ROOT       = File.join(File.dirname(__FILE__), '..')
 RAILS_ROOT = ROOT
+RAILS_ENV  = "test"
 
 $LOAD_PATH << File.join(ROOT, 'lib')
 $LOAD_PATH << File.join(ROOT, 'lib', 'paperclip')

test/interpolations_test.rb

+require 'test/helper'
+
+class InterpolationsTest < Test::Unit::TestCase
+  should "return all methods but the infrastructure when sent #all" do
+    methods = Paperclip::Interpolations.all
+    assert ! methods.include?(:[])
+    assert ! methods.include?(:[]=)
+    assert ! methods.include?(:all)
+    methods.each do |m|
+      assert Paperclip::Interpolations.respond_to? m
+    end
+  end
+
+  should "return the RAILS_ROOT" do
+    assert_equal RAILS_ROOT, Paperclip::Interpolations.rails_root(:attachment, :style)
+  end
+
+  should "return the RAILS_ENV" do
+    assert_equal RAILS_ENV, Paperclip::Interpolations.rails_env(:attachment, :style)
+  end
+
+  should "return the class of the instance" do
+    attachment = mock
+    attachment.expects(:instance).returns(attachment)
+    attachment.expects(:class).returns("Thing")
+    assert_equal "things", Paperclip::Interpolations.class(attachment, :style)
+  end
+
+  should "return the basename of the file" do
+    attachment = mock
+    attachment.expects(:original_filename).returns("one.jpg").times(2)
+    assert_equal "one", Paperclip::Interpolations.basename(attachment, :style)
+  end
+
+  should "return the extension of the file" do
+    attachment = mock
+    attachment.expects(:original_filename).returns("one.jpg")
+    attachment.expects(:styles).returns({})
+    assert_equal "jpg", Paperclip::Interpolations.extension(attachment, :style)
+  end
+
+  should "return the extension of the file as the format is defined in the style" do
+    attachment = mock
+    attachment.expects(:original_filename).never
+    attachment.expects(:styles).returns({:style => {:format => "png"}})
+    assert_equal "png", Paperclip::Interpolations.extension(attachment, :style)
+  end
+
+  should "return the id of the attachment" do
+    attachment = mock
+    attachment.expects(:id).returns(23)
+    attachment.expects(:instance).returns(attachment)
+    assert_equal 23, Paperclip::Interpolations.id(attachment, :style)
+  end
+
+  should "return the partitioned id of the attachment" do
+    attachment = mock
+    attachment.expects(:id).returns(23)
+    attachment.expects(:instance).returns(attachment)
+    assert_equal "000/000/023", Paperclip::Interpolations.id_partition(attachment, :style)
+  end
+
+  should "return the name of the attachment" do
+    attachment = mock
+    attachment.expects(:name).returns("file")
+    assert_equal "files", Paperclip::Interpolations.attachment(attachment, :style)
+  end
+
+  should "return the style" do
+    assert_equal :style, Paperclip::Interpolations.style(:attachment, :style)
+  end
+
+  should "return the default style" do
+    attachment = mock
+    attachment.expects(:default_style).returns(:default_style)
+    assert_equal :default_style, Paperclip::Interpolations.style(attachment, nil)
+  end
+end