get_proxy_from_env

# File lib/rubygems/request.rb, line 164
  def self.get_proxy_from_env(scheme = 'http')
    _scheme = scheme.downcase
    _SCHEME = scheme.upcase
    env_proxy = ENV["#{_scheme}_proxy"] || ENV["#{_SCHEME}_PROXY"]

    no_env_proxy = env_proxy.nil? || env_proxy.empty?

    return get_proxy_from_env 'http' if no_env_proxy and _scheme != 'http'
    return :no_proxy                 if no_env_proxy

    uri = URI(Gem::UriFormatter.new(env_proxy).normalize)

    if uri and uri.user.nil? and uri.password.nil?
      user     = ENV["#{_scheme}_proxy_user"] || ENV["#{_SCHEME}_PROXY_USER"]
      password = ENV["#{_scheme}_proxy_pass"] || ENV["#{_SCHEME}_PROXY_PASS"]

      uri.user     = Gem::UriFormatter.new(user).escape
      uri.password = Gem::UriFormatter.new(password).escape
    end

    uri
  end