While converting my app from rails 3.0 to 3.1 I had an issue getting bootstrap working with the asset pipe line after digging a while here is what I had to do.
In application.css
/**
= require ./bootstrap/bootstrap*
= require_tree ./smoothness*=
require_self
*/
Rename bootstrap.less to bootstrap.css.less.erb
In bootstrap.css.less.erb remove what is there and put in
<%= File.read "#{Rails.root}/app/assets/stylesheets/bootstrap/reset.css.less" %>
<%= File.read "#{Rails.root}/app/assets/stylesheets/bootstrap/preboot.css.less" %>
<%= File.read "#{Rails.root}/app/assets/stylesheets/bootstrap/scaffolding.css.less" %>
<%= File.read "#{Rails.root}/app/assets/stylesheets/bootstrap/type.css.less" %>
<%= File.read "#{Rails.root}/app/assets/stylesheets/bootstrap/forms.css.less" %>
<%= File.read "#{Rails.root}/app/assets/stylesheets/bootstrap/tables.css.less" %>
<%= File.read "#{Rails.root}/app/assets/stylesheets/bootstrap/patterns.css.less" %>
Next rename all bootstrap files to *.css.less
Then in my GemFile
group :assets do
gem 'sass-rails', " ~> 3.1.0"
gem 'coffee-rails', "~> 3.1.0"
gem 'less'
gem 'uglifier'
end
That was it.