Fixes validates_attachment_presence just flat out not working

lib/paperclip.rb

@@ -388,7 +388,9 @@ module Paperclip
     def validates_attachment_presence name, options = {}
       message = options[:message] || :empty
       validates_each :"#{name}_file_name" do |record, attr, value|
-        record.errors.add(name, message) if attr.blank?
+        if_clause_passed = options[:if].nil? || (options[:if].call(record) != false)
+        unless_clause_passed = options[:unless].nil? || (!!options[:unless].call(record) == false)
+        record.errors.add(name, message) if if_clause_passed && unless_clause_passed && value.blank?
       end
     end
 

test/paperclip_test.rb

@@ -238,7 +238,7 @@ class PaperclipTest < Test::Unit::TestCase
             @dummy.avatar = valid_file
             @dummy.valid?
           end
-          should "not have an error when assigned a valid file" do
+          should "not have an error" do
             assert_equal 0, @dummy.errors.size, @dummy.errors.full_messages.join(", ")
           end
         end
@@ -247,7 +247,7 @@ class PaperclipTest < Test::Unit::TestCase
             @dummy.avatar = invalid_file
             @dummy.valid?
           end
-          should "have an error when assigned a valid file" do
+          should "have an error" do
             assert @dummy.errors.size > 0
           end
         end