Ruby gem environment issue - LoadError: no such file to load -- robots

Question

I'm attempting to write a crawler using the anemone gem, which requires the robots gem. For whatever reason, robots absolutely will not include. Here is some of my environment info:

$ gem list -d robots

*** LOCAL GEMS ***

robots (0.10.1)
    Author: Kyle Maxwell
    Homepage: http://github.com/fizx/robots
    Installed at: /usr/local/lib/ruby/gems/1.9.1

    Simple robots.txt parser

$ gem env
RubyGems Environment:
  - RUBYGEMS VERSION: 1.8.10
  - RUBY VERSION: 1.9.2 (2011-02-18 patchlevel 180) [x86_64-darwin10.7.0]
  - INSTALLATION DIRECTORY: /usr/local/lib/ruby/gems/1.9.1
  - RUBY EXECUTABLE: /usr/local/bin/ruby
  - EXECUTABLE DIRECTORY: /usr/local/bin
  - RUBYGEMS PLATFORMS:
    - ruby
    - x86_64-darwin-10
  - GEM PATHS:
     - /usr/local/lib/ruby/gems/1.9.1
     - /Users/ryan/.gem/ruby/1.9.1
  - GEM CONFIGURATION:
     - :update_sources => true
     - :verbose => true
     - :benchmark => false
     - :backtrace => false
     - :bulk_threshold => 1000
  - REMOTE SOURCES:
     - http://rubygems.org/

$ gem which robots
/usr/local/lib/ruby/gems/1.9.1/gems/robots-0.10.1/lib/robots.rb

Any ideas? All other gems load correctly, I've never had this problem before. Note that I am using ruby version 1.9, so rubygems is implicitly required. Adding

require 'rubygems'

...to the front of a script returns false, since the file is already included, and does not help the situation. Any ideas?

EDIT: Posting examples of failing code. Please note that rubygems returning false does not mean rubygems cannot load - rather that it has already been loaded. See this post: http://www.ruby-forum.com/topic/157442

$ irb
irb(main):001:0> require 'rubygems'
=> false
irb(main):002:0> require 'active_record'
=> true
irb(main):003:0> require 'mechanize'
=> true
irb(main):004:0> require 'robots'
LoadError: no such file to load -- robots
    from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:59:in `require'
    from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:59:in `rescue in require'
    from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:35:in `require'
    from (irb):4
    from /usr/local/bin/irb:12:in `<main>'
irb(main):005:0> 

Answer 1

It looks like the gem has been created with the wrong permissions; there's a bug opened for this on github.

Changing the permissions with

sudo chmod a+r /usr/local/lib/ruby/gems/1.9.1/gems/robots-0.10.1/lib/robots.rb

should fix it, but watch out for other permission issues. You might be better with

sudo chmod -R a+r /usr/local/lib/ruby/gems/1.9.1/gems/robots-0.10.1

to recursively make all the files in the gem readable.

The robots.rb file (and some others) is being installed with the permissions -rw-rw----, so anyone using a local install of rvm or similar where gems are installed as the local user won't have been affected by this.