Added Paperclip::Processor as a necessary superclass of Thumbnail (and all processors)

lib/paperclip.rb

@@ -29,9 +29,15 @@ require 'tempfile'
 require 'paperclip/upfile'
 require 'paperclip/iostream'
 require 'paperclip/geometry'
+require 'paperclip/processor'
 require 'paperclip/thumbnail'
 require 'paperclip/storage'
 require 'paperclip/attachment'
+if defined? RAILS_ROOT
+  Dir.glob(File.join(File.expand_path(RAILS_ROOT), "lib", "paperclip_processors", "*.rb")).each do |processor|
+    require processor
+  end
+end
 
 # The base module that gets included in ActiveRecord::Base. See the
 # documentation for Paperclip::ClassMethods for more useful information.
@@ -81,7 +87,9 @@ module Paperclip
 
     def processor name
       name = name.to_s.camelize
-      Paperclip.const_get(name) if Paperclip.const_defined?(name)
+      processor = Paperclip.const_get(name)
+      raise PaperclipError.new("Processor #{name} was not found") unless processor.ancestors.include?(Paperclip::Processor)
+      processor
     end
   end
 

lib/paperclip/processor.rb

+module Paperclip
+  class Processor
+    attr_accessor :file, :options
+
+    def initialize file, options = {}
+      @file = file
+      @options = options
+    end
+
+    def make
+    end
+
+    def self.make file, options = {}
+      new(file, options).make
+    end
+  end
+end

lib/paperclip/thumbnail.rb

 module Paperclip
   # Handles thumbnailing images that are uploaded.
-  class Thumbnail
+  class Thumbnail < Processor
 
-    attr_accessor :file, :current_geometry, :target_geometry, :format, :whiny, :convert_options
+    attr_accessor :current_geometry, :target_geometry, :format, :whiny, :convert_options
 
     # Creates a Thumbnail object set to work on the +file+ given. It
     # will attempt to transform the image into one defined by +target_geometry+
@@ -11,6 +11,7 @@ module Paperclip
     # +whiny+ is true (which it is, by default. If +convert_options+ is
     # set, the options will be appended to the convert command upon image conversion 
     def initialize file, options = {}
+      super
       geometry          = options[:geometry]
       @file             = file
       @crop             = geometry[-1,1] == '#'
@@ -24,12 +25,6 @@ module Paperclip
       @basename         = File.basename(@file.path, @current_format)
     end
 
-    # Creates a thumbnail, as specified in +initialize+, +make+s it, and returns the
-    # resulting Tempfile.
-    def self.make file, options = {}
-      new(file, options).make
-    end
-
     # Returns true if the +target_geometry+ is meant to crop.
     def crop?
       @crop

test/paperclip_test.rb

@@ -32,8 +32,12 @@ class PaperclipTest < Test::Unit::TestCase
     end
   end
 
-  should "return nil when sent #processor and the name of a class that doesn't exist" do
-    assert_nil Paperclip.processor(:boogey_man)
+  should "raise when sent #processor and the name of a class that exists but isn't a subclass of Processor" do
+    assert_raises(Paperclip::PaperclipError){ Paperclip.processor(:attachment) }
+  end
+
+  should "raise when sent #processor and the name of a class that doesn't exist" do
+    assert_raises(NameError){ Paperclip.processor(:boogey_man) }
   end
 
   should "return a class when sent #processor and the name of a class under Paperclip" do

test/processor_test.rb

+require 'test/helper'
+
+class ProcessorTest < Test::Unit::TestCase
+  should "instantiate and call #make when sent #make to the class" do
+    processor = mock
+    processor.expects(:make).with()
+    Paperclip::Processor.expects(:new).with(:one, :two).returns(processor)
+    Paperclip::Processor.make(:one, :two)
+  end
+end