download

# File lib/rubygems/test_utilities.rb, line 137
  def download spec, source_uri, install_dir = Gem.dir
    name = File.basename spec.cache_file
    path = if Dir.pwd == install_dir then # see fetch_command
             install_dir
           else
             File.join install_dir, "cache"
           end

    path = File.join path, name

    if source_uri =~ /^http/ then
      File.open(path, "wb") do |f|
        f.write fetch_path(File.join(source_uri, "gems", name))
      end
    else
      FileUtils.cp source_uri, path
    end

    path
  end