Fixed a bug where #class scanning would error on the Interpolations module

lib/paperclip/interpolations.rb

@@ -63,7 +63,10 @@ module Paperclip
 
     # Returns the underscored, pluralized version of the class name.
     # e.g. "users" for the User class.
-    def class attachment, style
+    # NOTE: The arguments need to be optional, because some tools fetch
+    # all class names. Calling #class will return the expected class.
+    def class attachment = nil, style = nil
+      return super() if attachment.nil? && style.nil?
       attachment.instance.class.to_s.underscore.pluralize
     end
 

test/interpolations_test.rb

@@ -19,6 +19,10 @@ class InterpolationsTest < Test::Unit::TestCase
     assert_equal RAILS_ENV, Paperclip::Interpolations.rails_env(:attachment, :style)
   end
 
+  should "return the class of the Interpolations module when called with no params" do
+    assert_equal Module, Paperclip::Interpolations.class
+  end
+
   should "return the class of the instance" do
     attachment = mock
     attachment.expects(:instance).returns(attachment)