check_that_user_bin_dir_is_in_path

# File lib/rubygems/installer.rb, line 671
  def check_that_user_bin_dir_is_in_path # :nodoc:
    user_bin_dir = @bin_dir || Gem.bindir(gem_home)
    user_bin_dir = user_bin_dir.gsub(File::SEPARATOR, File::ALT_SEPARATOR) if
      File::ALT_SEPARATOR

    path = ENV['PATH']
    if Gem.win_platform? then
      path = path.downcase
      user_bin_dir = user_bin_dir.downcase
    end

    path = path.split(File::PATH_SEPARATOR)

    unless path.include? user_bin_dir then
      unless !Gem.win_platform? && (path.include? user_bin_dir.sub(ENV['HOME'], '~'))
        unless self.class.path_warning then
          alert_warning "You don't have #{user_bin_dir} in your PATH,\n\t  gem executables will not run."
          self.class.path_warning = true
        end
      end
    end
  end