"Invalid gemspec messages" during "install package" girl factory (rails 3.1 and ruby ​​1.9.2p290)

Note:
I asked this question when I got unexpected messages while executing bundle install

with a gem factory_girl

using Ubuntu 11.10. As a nob, I had ... and still ... don't know what's going on. The update below attempts to describe what I did to get rid of the messages eventually. I leave the question with a slightly more appropriate title line in case it might be useful to someone else.

I look at Factory Girl README.md and I see:

    Install
      gem install factory_girl
    or add the following line to Gemfile:
      gem 'factory_girl'
    and run bundle install from your shell.

    Supported Ruby versions
    The Factory Girl 3.x series supports Ruby 1.9.x.
    For older versions of Ruby, please use the Factory Girl 2.x series.

Since I am currently using Rails 3.1.0

and
ruby 1.9.2p290 (2011-07-09 revision 32553) [i686-linux]

I add gem 'factory_girl'

to my Gemfile and do bundle update

.

But then, continuing, I open Getting Started.md and read

    Update Your Gemfile
    If you're using Rails, you'll need to change
    the required version of factory_girl_rails:
      gem "factory_girl_rails", "~> 2.0"
    If you're not using Rails, you'll just have to
    change the required version of factory_girl:
      gem "factory_girl", "~> 3.0"
    Once your Gemfile is updated, you'll want to update your bundle.

Good perfect. I am removing gem 'factory_girl'

from my Gemfile and adding instead gem "factory_girl_rails", "~> 2.0"

.
Then I will try bundle update

again. No joy this time.

    $ bundle install
    Invalid gemspec in [/usr/local/lib/ruby/gems/1.9.1/specifications/
      factory_girl_rails-2.0.0.gemspec]: Illformed requirement
      ["# 3.0.7"]
    Invalid gemspec in [/usr/local/lib/ruby/gems/1.9.1/specifications/
      factory_girl_rails-2.0.0.gemspec]: Illformed requirement 
      ["# 3.0.7"]
    Fetching source index for http://rubygems.org/
    Using rake (0.9.2.2) 
    Using ZenTest (4.7.0) 
    ... a bunch of "Using" lines omitted for brevity ...
    Using deepopenstruct (0.1.2) 
    Using factory_girl (3.0.0) 
    Installing factory_girl_rails (2.0.0) Invalid gemspec in
      [/usr/local/lib/ruby/gems/1.9.1/specifications/factory_girl_rails-2.0.0.gemspec]:
      Illformed requirement ["# 3.0.7"]  
    Using haml (3.1.4) 
    Using jquery-rails (1.0.19) 
    ... a bunch of "Using" lines omitted for brevity ...
    Using uglifier (1.2.4) 
    Your bundle is complete! Use `bundle show [gemname]` to see where a
      bundled gem is installed.

So now I'm wondering (1) why the following instructions in the README clearly didn't work and (2) what should I do with my Gemfile to get the Factory Girl smiling and productive?

Update

When getting error messages that I don't understand, it's frustrating to get rid of them, but really not sure what I did, I'm wrong, "fixing" things is also less special. Oh good.

To be honest, although I used the package, I had no idea what the difference was between gem

, rvm

and bundle

, and I really don't understand what each command is supposed to do. I think this blog post I found via google helped somewhat: RVM and Bundler in five seconds

Thinking that rvm and bundle should automate the management of a group of gems, but gem

just manage the gems, I looked at the gems teams.

I tried gem check

which IIRC did nothing. Then I tried gem cleanup

, which came back with a long list of gems it wanted to remove. Trusting that I would (possibly) get back to where I needed help bundle install

, I allowed him to do remote links. (Although I had to use sudo gem cleanup

it because I lacked written permission for some of the related directories).

After that gem check

, gem cleanup

they returned clean. However bundle check

returned:

The following gems are missing
 * activesupport (3.1.0)
 * activemodel (3.1.0)
 * rack-cache (1.0.3)
 * actionpack (3.1.0)
Install missing gems with `bundle install`

So, I did both bundle install

and then (why not?) bundle update

. This installed the gems listed above without issue. In particular, this time I did not get Invalid gemspec

any or any other error messages. (Hooray!)

Of course bundle update

not doing anything, to be honest, I expected him to do it.

So while I'm not sure yet what happened, the original reason for my question was curious, it has been resolved.

I'll leave this question unanswered for a week or so, to see if anyone else wants to contribute any comments. After that, if no one else provides a more informative answer, I think I'll just "answer" this question to close it.

Thanks to everyone who helped push me towards cleaner gem sets.