Upgraded to rails 3, and using Bundler for gems, in a mixed platform development group. I am on Windows. When I run Bundle Install it completes succesfully but will not install hpricot. The hpricot line is:
gem "hpricot", "0.8.3", :platform => :mswin
also tried
gem "hpricot", :platform => :mswin
Both complete fine but when I try to do a "bundle show hpricot" I get:
Could not find gem 'hpricot' in the current bundle.
If I do a run a rails console and try "require 'hpricot'" I get:
LoadError: no such file to load -- hpricot
I have manually installed hpricot as well, and still get the above error. This worked fine before moving to rails 3.
Try this in console and then do bundle install, it will work:
gem install hpricot --platform=mswin32
It may be that you are using a version of ruby that was built with MinGW in which case your platform will be 'mingw' rather than 'mswin'. Try changing your Gemfile line to the following:
gem "hpricot", "0.8.3", :platform => :mingw
And if you have other developers that are using the current setup and don't wan to break it for them, change it to this:
gem "hpricot", "0.8.3", :platforms => [:mswin, :mingw]
来源：https://stackoverflow.com/questions/4159189/rails-bundler-on-windows-refuses-to-install-hpricot-even-on-manual-gem-install