Q:

How do I test a paperclip URL?

I'm using Test::Unit, and I'd like to test a paperclip url.
Right now, I have a test that looks like this:
  def test_our_custom_url
    dummy = Dummy.new(:image => File.open("#{RAILS_ROOT}/test/fixtures/12k.png"))
    dummy.save!
    assert_match "/system/images/1/original/12k.png", dummy.image.url
    dummy.reload
    assert_match "/system/images/1/original/12k.png", dummy.image.url
  end

And it fails like this:
Expected /\/system\/images\/1\/original\/12k.png/ to match "/system/dummies/images/000/000/001/original/12k.png?1352140343".

How can I get the ?1352140343 part added to the test? 
I see in paperclips source code that they seem to define it like this:
def timestamp_as_needed(url, options)
  if options[:timestamp] && timestamp_possible?
    delimiter_char = url.match(/\?.+=/) ? '&' : '?'
    "#{url}#{delimiter_char}#{@attachment.updated_at.to_s}"
  else
    url
  end
end

but doing dummy.updated_at.to_s returns a normal date/timestamp, not 1352140343 (in this case). 
I'm using local storage, if it makes a difference.

A:

Its not good to compare the ?1352140343 part of the url.
you can compare your received_url.starts_with?(expected_url) to check only that part of the strings...

