Run specific directories with rspec & rcov

[:models, :controllers, :views, :helpers, :lib, :mailers, :observers, :middleware].each do |sub|
    desc "Run #{sub} specs with rcov"
    Spec::Rake::SpecTask.new("rcov:#{sub}" => spec_prereq) do |t|
      t.spec_opts = ['--options', "\"#{RAILS_ROOT}/spec/spec.opts\""]
      t.spec_files = FileList["spec/#{sub}/**/*_spec.rb"]
      t.rcov = true
      
      # create exclusion patterns since there no "inlucde only" option with rspec
      directories = [:models, :controllers, :views, :helpers, :lib, :mailers, :observers, :middleware].reject {|dir| dir == sub}
      patterns = directories.map {|dir| "\"#{dir}/*\""}
      defaults = ['"spec/*"', '"gems/*"']      
      excludes = "--exclude " + (patterns + defaults).join(',')
      
      t.rcov_opts = [excludes, '--rails']
    end
  end