vendor/rails/railties/doc/guides/source/creating_plugins/helpers.txt

   1 == Add a helper ==
   2
   3 This section describes how to add a helper named 'WoodpeckersHelper' to your plugin that will behave the same as a helper in your main app.  This is very similar to adding a model and a controller.
   4
   5 You can test your plugin's helper as you would test any other helper:
   6
   7 *vendor/plugins/yaffle/test/woodpeckers_helper_test.rb*
   8
   9 [source, ruby]
  10 ---------------------------------------------------------------
  11 require File.dirname(__FILE__) + '/test_helper.rb'
  12 include WoodpeckersHelper
  13
  14 class WoodpeckersHelperTest < Test::Unit::TestCase
  15   def test_tweet
  16     assert_equal "Tweet! Hello", tweet("Hello")
  17   end
  18 end
  19 ---------------------------------------------------------------
  20
  21 This is just a simple test to make sure the helper is being loaded correctly.  After watching it fail with `rake`, you can make it pass like so:
  22
  23 *vendor/plugins/yaffle/lib/yaffle.rb:*
  24
  25 [source, ruby]
  26 ----------------------------------------------
  27 %w{ models controllers helpers }.each do |dir|
  28   path = File.join(File.dirname(__FILE__), 'app', dir)
  29   $LOAD_PATH << path
  30   ActiveSupport::Dependencies.load_paths << path
  31   ActiveSupport::Dependencies.load_once_paths.delete(path)
  32 end
  33
  34 ActionView::Base.send :include, WoodpeckersHelper
  35 ----------------------------------------------
  36
  37
  38 *vendor/plugins/yaffle/lib/app/helpers/woodpeckers_helper.rb:*
  39
  40 [source, ruby]
  41 ----------------------------------------------
  42 module WoodpeckersHelper
  43
  44   def tweet(text)
  45     "Tweet! #{text}"
  46   end
  47
  48 end
  49 ----------------------------------------------
  50
  51 Now your test should be passing, and you should be able to use the Woodpeckers helper in your app.