# File lib/rubygems/commands/dependency_command.rb, line 45
  def execute
    options[:args] << '.' if options[:args].empty?
    specs = {}

    source_indexes = []

    if local? then
      source_indexes << Gem::SourceIndex.from_installed_gems
    end

    if remote? then
      Gem::SourceInfoCache.cache_data.map do |_, sice|
        source_indexes << sice.source_index
      end
    end

    options[:args].each do |name|
      new_specs = nil
      source_indexes.each do |source_index|
        new_specs =  find_gems(name, source_index)
      end

      say "No match found for #{name} (#{options[:version]})" if
        new_specs.empty?

      specs = specs.merge new_specs
    end

    terminate_interaction 1 if specs.empty?

    reverse = Hash.new { |h, k| h[k] = [] }

    if options[:reverse_dependencies] then
      specs.values.each do |source_index, spec|
        reverse[spec.full_name] = find_reverse_dependencies spec, source_index
      end
    end

    if options[:pipe_format] then
      specs.values.sort_by { |_, spec| spec }.each do |_, spec|
        unless spec.dependencies.empty?
          spec.dependencies.each do |dep|
            say "#{dep.name} --version '#{dep.version_requirements}'"
          end
        end
      end
    else
      response = ''

      specs.values.sort_by { |_, spec| spec }.each do |_, spec|
        response << print_dependencies(spec)
        unless reverse[spec.full_name].empty? then
          response << "  Used by\n"
          reverse[spec.full_name].each do |sp, dep|
            response << "    #{sp} (#{dep})\n"
          end
        end
        response << "\n"
      end

      say response
    end
  end