require 'fileutils'
require 'open3'

module Gitlab
  module Popen
    extend self

    def popen(cmd, path = nil, vars = {})
      unless cmd.is_a?(Array)
        raise "System commands must be given as an array of strings"
      end

      path ||= Dir.pwd
      vars['PWD'] = path
      options = { chdir: path }

      unless File.directory?(path)
        FileUtils.mkdir_p(path)
      end

      cmd_output = ""
      cmd_status = 0
      Open3.popen3(vars, *cmd, options) do |stdin, stdout, stderr, wait_thr|
        yield(stdin) if block_given?
        stdin.close

        cmd_output << stdout.read
        cmd_output << stderr.read
        cmd_status = wait_thr.value.exitstatus
      end

      [cmd_output, cmd_status]
    end
  end
end
