# File lib/bundler/graph.rb, line 6
    def initialize(env, output_file, show_version = false, show_requirements = false, output_format = "png")
      @env               = env
      @output_file       = output_file
      @show_version      = show_version
      @show_requirements = show_requirements
      @output_format     = output_format

      @groups            = []
      @relations         = Hash.new {|h, k| h[k] = Set.new}
      @node_options      = {}
      @edge_options      = {}

      _populate_relations
    end