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It’s been awhile since I wrote here, having been busy with my usual tagging ideas. Since last time I wrote, I’ve released two public pieces of rails-related code! : a patch for nested sets as well as my first gem. All shameless plugs aside, I came here to share some old code I revived and a practical use I found for it. The code is here

My goal awhile back was to be able to quickly understand any ruby code given to me. To put myself on that path I did two things: learn to debug Ruby thoroughly with Kernel::set_trace_func and parse ruby files. I wanted to parse ruby files so I could get a quick overview of a file’s classes and their methods. I looked at ParseTree and then rdoc’s parser. Of the two, rdoc seemed to be a little higher level and so the core method looks like:

def rdoc_parse_file(file)
  class_hash = {}
  content = File.open(file, "r") {|f| f.read}
  capital_p = RDoc::ParserFactory.parser_for(RDoc::TopLevel.new(file),file,content,Options.instance,RDoc::Stats.new)
  capital_p.scan
  rclasses = RDoc::TopLevel.all_classes_and_modules
  rclasses.each {|rc| index_class(rc,class_hash) }
  RDoc::TopLevel::reset
  class_hash
end

That little bit opens a file, scans it with rdoc and then saves the methods by class with the recursive function index_class(). If you look at the full version you’ll probably laugh at how small index_class() is.

Since writing rdoc_parse_file(), I’ve been taking apart and writing rails apps. So I recently combined the two. Overview.rb is a script you can drop into you rails script directory to provide a handy outline of the classes and methods by directory under app/. I use it for note taking when dealing with a new rails app.

A sample output of the snippets rails app :

controllers
    UserController:
      - show
    PostsController:
      - create
      - destroy
      - edit
      - index
      - show
      - update
    TagController:
      - show
    ApplicationController:
      - admin_or_post_owner
      - check_if_visitor_allowed
      - get_page_number
      - get_related_posts
      - get_tag_info
      - get_user_info
      - is_ticketed
      - redirect_back
      - store_locations
    LoginController:
      - account
      - create
      - login
      - logout
      - new
      - update
    CommentsController:
      - create
helpers
    TagsHelper: []
    LoginHelper: []
    UserHelper: []
    PostsHelper: []
    CommentsHelper: []
    ApplicationHelper:
      - niceify_html
      - niceify_html_for_rss
      - page_title
      - rounded_box_bottom
      - rounded_box_top
      - tag_link
models
    Comment: []
    User:
      - authenticate
      - change_password
      - crypt_password
      - find_with_count
      - "isAdmin?" 
      - "isAdmin?" 
      - sha1
    Tag:
      - find_all_with_count
      - find_all_with_count_for_tags
      - find_all_with_count_for_user
      - find_by_name_with_count
    Post:
      - find_related_posts
      - pagetitle
      - tagsspaced
      - tagsspaced=

Enjoy. And let me know if you tweak this script in a cool way.