method_extensions

method_extensions

Adds the following method to the Method/UnboundMethod objects

• source - finds method source based on source_location and Ripper parser
• doc - returns the comment preceding method definition
• super - returns method which will be called if given Method/UnboundMethod would
  call super. Chainable. Available only after you require "method_extensions/method/super"

And some sugar

• source_with_doc - source + doc
• full_inspect - inspect + source_location + source_with_doc

Installation

gem install method_extensions

Usage

See how method_extensions can be used to look under the hood of a few Rails 3
core methods at my blog post Travel To The Core Rails 3 Methods Without Leaving IRB Prompt.

> irb
ruby-1.9.2-head > require "method_extensions"
ruby-1.9.2-head > require "fileutils"
ruby-1.9.2-head > puts FileUtils.method(:mkdir).source_with_doc
#
# Options: mode noop verbose
#
# Creates one or more directories.
#
#   FileUtils.mkdir 'test'
#   FileUtils.mkdir %w( tmp data )
#   FileUtils.mkdir 'notexist', :noop => true  # Does not really create.
#   FileUtils.mkdir 'tmp', :mode => 0700
#
def mkdir(list, options = {})
  fu_check_options options, OPT_TABLE['mkdir']
  list = fu_list(list)
  fu_output_message "mkdir #{options[:mode] ? ('-m %03o ' % options[:mode]) : ''}#{list.join ' '}" if options[:verbose]
  return if options[:noop]

  list.each do |dir|
    fu_mkdir dir, options[:mode]
  end
end


ruby-1.9.2-head > eval <<-CODE 
  class Base
    def meth; end
  end

  class Derived < Base
    def meth; end
  end
CODE

ruby-1.9.2-head > Derived.instance_method(:meth)
=> #<UnboundMethod: Derived#meth>

ruby-1.9.2-head > Derived.instance_method(:meth).super
=> #<UnboundMethod: Base#meth>