From DevchixWiki
$ sudo gem install rspec rspec-rails cucumber webrat --no-rdoc --no-ri
**************************************************
Thank you for installing rspec-1.2.8
Please be sure to read History.rdoc and Upgrade.rdoc
for useful information about this release.
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Successfully installed rspec-1.2.8
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Thank you for installing rspec-rails-1.2.7.1
If you are upgrading, do this in each of your rails apps
that you want to upgrade:
$ ruby script/generate rspec
Please be sure to read History.rdoc and Upgrade.rdoc
for useful information about this release.
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Successfully installed rspec-rails-1.2.7.1
Successfully installed cucumber-0.3.102
Successfully installed webrat-0.5.3
4 gems installed