Moved the geometry proc running to assignment instead of initialization

lib/paperclip/attachment.rb

@@ -90,6 +90,7 @@ module Paperclip
 
       @dirty = true
 
+      solidify_style_definitions
       post_process if valid?
  
       # Reset the file size if the original file was reprocessed.
@@ -303,6 +304,11 @@ module Paperclip
             :convert_options => extra_options_for(name)
           }.merge(@styles[name])
         end
+      end
+    end
+
+    def solidify_style_definitions #:nodoc:
+      @styles.each do |name, args|
         if @styles[name][:geometry].respond_to?(:call)
           @styles[name][:geometry] = @styles[name][:geometry].call(instance) 
         end

test/attachment_test.rb

@@ -182,11 +182,22 @@ class AttachmentTest < Test::Unit::TestCase
         @attachment = Dummy.new.avatar
       end
 
+      should "not run the procs immediately" do
+        assert_kind_of Proc, @attachment.styles[:normal][:geometry]
+      end
+
+      context "when assigned" do
+        setup do
+          @file = StringIO.new(".")
+          @attachment.assign(@file)
+        end
+
         should "have the correct geometry" do
           assert_equal "50x50#", @attachment.styles[:normal][:geometry]
         end
       end
     end
+  end
 
   context "An attachment with both 'normal' and hash-style styles" do
     setup do