Gem::Exception: can't activate , already activated x

By: Johnathon Wright on: August 05, 2009

I recently saw this exception: [RAILS_ROUTE] /config/../vendor/rails/railties/lib/rails/gemdependency.rb:101:in `specification':Gem::Exception: can't activate , already activated *gemname*

This exception seemed to be the result of several problems intermingling:

  1. rake gems:install wouldn't work because the config.gem statements were in config/environments/test.rb. Only the gems listed in config/environment.rb are installed in gems:install (though I didn't try to manually set the environment to test...)
  2. I had the wrong version of nokogiri. The configuration specified a certain version, instead of any version greater than a certain version.
  3. I also didn't have the gem listed after the gem with the wrong version. When I modified test.rb so that only the gem with the wrong version was listed, I got a more helpful error: Missing these required gems: gem_name = version You're running:ruby 1.8.6.287 at path rubygems 1.3.3 at path

So, the solution: 1. Once I found the gem requirements in test.rb, I deleted half of them and ran script/console. I kept deleting chunks of the requirements until the error went away. 2. Installed the correct version It seems simple in retrospect... but the error was very confusing.



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