This post originated from an RSS feed registered with Ruby Buzz by Eric Hodel. Original Post: render_tree for Rails Feed Title: Segment7 Feed URL: http://blog.segment7.net/articles.rss Feed Description: Posts about and around Ruby, MetaRuby, ruby2c, ZenTest and work at The Robot Co-op. Latest Ruby Buzz Posts Latest Ruby Buzz Posts by Eric Hodel Latest Posts From Segment7

Spelunking deep in unfamiliar Rails view code? Flushing out the cobwebs and updating your code? Don't know what gets rendered when?

I have a solution for you:

class ActionView::Base

  alias plain_render render

  RENDERS = [:partial, :template, :file, :action, :text, :inline, :nothing,
             :update]

  def render(*args)
    @level ||= 0

    print '  ' * @level

    case args.first
    when String then
      p args.first
    when Hash then
      hash = args.first
      found = hash.keys & RENDERS
      if found.length == 1 then
        puts "%p => %p" % [found.first, hash[found.first]]
      else
        raise "Dunno: %p" % [hash]
      end
    else
      raise "Dunno: %p" % [args]
    end

    @level += 1
    result = plain_render(*args)
    @level -= 1
    result
  end

end

Drop that in test/render_tree.rb and require it in your tests when you want to see a tree like this:

$ ruby test/views/things_view_test.rb -n test_view
Loaded suite test/views/things_view_test
Started
"things/things-header"
  "things/sidebar"
    "widgets/forms/goal_form"
    :partial => "widgets/sidenav_boxes/invite_and_edit"
      "widgets/sidenav_boxes/_invite_and_edit"
    :partial => "widgets/forms/edit_worth_doing_form"
      "widgets/forms/_edit_worth_doing_form"
    :partial => "widgets/sidenav_boxes/tags"
      "widgets/sidenav_boxes/_tags"
    :partial => "widgets/sidenav_boxes/popular_places"
      "widgets/sidenav_boxes/_popular_places"
    :partial => "widgets/sidenav_boxes/google_ads"
      "widgets/sidenav_boxes/_google_ads"
    :partial => "widgets/sidenav_boxes/find_help"
      "widgets/sidenav_boxes/_find_help"
    :partial => "widgets/sidenav_boxes/people_who_reached_this_goal"
      "widgets/sidenav_boxes/_people_who_reached_this_goal"
    :partial => "widgets/sidenav_boxes/quotation"
      "widgets/sidenav_boxes/_quotation"
    :partial => "widgets/sidenav_boxes/goal_created_by"
      "widgets/sidenav_boxes/_goal_created_by"
"widgets/general/post_add_messages"
"things/shared_body"
  :partial => "widgets/goals_gallery_teaser"
    "widgets/_goals_gallery_teaser"
  :partial => "entries_bucket"
    "things/_entries_bucket"
  "widgets/forms/related_goals"
.
Finished in 1.205494 seconds.

1 tests, 7 assertions, 0 failures, 0 errors

(I think I'll end up throwing this into ZenTest.)