gistfile1.rb

Then I should see :"flash.success.admin_signup" with email: "joedoe@example.com", first_name: "Joe"

Then /^I should see :"([^\"]*)"(?: with #{capture_fields})?$/ do |text, fields|
  if page.respond_to? :should
    page.should have_content(I18n.t(text, eval("{#{fields}}")))
  else
    assert page.has_content?(I18n.t(text, eval("{#{fields}}")))
  end
end