paulfioravanti / resume

  # Ensures that the version of Ruby being used is recent enough

  # to generate the resume.

  #

  # @author Paul Fioravanti

  module RubyVersionChecker

    # Required Ruby version for resume to work

    REQUIRED_RUBY_VERSION = ENV.fetch("CUSTOM_RUBY_VERSION", "2.6.3").freeze

    private_constant :REQUIRED_RUBY_VERSION

    # Ruby version command

    RUBY_VERSION_COMMAND = "ruby -v".freeze

    private_constant :RUBY_VERSION_COMMAND

    # Ruby version output regex.

    # For example, this will extract `2.6.3` from a string like:

    # ruby 2.6.3p62 (2019-04-16 revision 67580) [x86_64-darwin18]

    RUBY_VERSION_REGEX = /\Aruby ([\d\.][^p]+)/.freeze

    private_constant :RUBY_VERSION_REGEX

    module_function

    # Checks the Ruby version being used to generate the resume.

    #

    # @return [nil]

    #   if rubygems is successfully required and the Ruby version is either

    #   installed or not installed.

    # @note On the one-sheet resume, this check will only work for

    #   >= Ruby 2.1  Earlier versions will throw a syntax error.

    def check_ruby_version

      # require "rubygems" only needed for ruby pre-1.9.0

      # but it's safe for later versions (evaluates to false).

      require "rubygems"

      request_to_install_latest_ruby if old_ruby_version?

    rescue LoadError

      # NOTE: LoadError could occur if someone attempts to run

      # this with Ruby 1.8.7 and they don't have rubygems installed

      request_to_install_latest_ruby

    end

    def old_ruby_version?

      Gem::Version.new(RUBY_VERSION.dup) <

        Gem::Version.new(REQUIRED_RUBY_VERSION)

    end

    private_class_method :old_ruby_version?

    def user_ruby_version

      ruby_version =

        Open3.popen3(RUBY_VERSION_COMMAND) do |_stdin, stdout, _stderr, _wait|

          stdout.read

        end

      ruby_version.match(RUBY_VERSION_REGEX)[0]

    end

    private_class_method :user_ruby_version

  end

end