# File lib/chef-config/config.rb, line 996
    def self.export_proxy(scheme, path, user, pass)
      path = "#{scheme}://#{path}" unless path.include?("://")
      # URI.split returns the following parts:
      # [scheme, userinfo, host, port, registry, path, opaque, query, fragment]
      uri = Addressable::URI.encode(path, Addressable::URI)

      if user && !user.empty?
        userinfo = Addressable::URI.encode_component(user, USER)
        if pass
          userinfo << ":#{Addressable::URI.encode_component(pass, PASSWORD)}"
        end
        uri.userinfo = userinfo
      end

      path = uri.to_s
      ENV["#{scheme}_proxy".downcase] = path unless ENV["#{scheme}_proxy".downcase]
      ENV["#{scheme}_proxy".upcase] = path unless ENV["#{scheme}_proxy".upcase]
    end