# File lib/chef_zero/endpoints/environment_cookbook_versions_endpoint.rb, line 112
      def filter_by_constraint(versions, cookbook_name, constraint)
        return versions if !constraint
        constraint = Gem::Requirement.new(constraint)
        new_versions = versions[cookbook_name]
        new_versions = new_versions.select { |version| constraint.satisfied_by?(Gem::Version.new(version.dup)) }
        result = versions.clone
        result[cookbook_name] = new_versions
        result
      end