Helper for testing executable in gem.

test_helper.rb

require 'open3'
def ruby_run(cmd, stdin_str)
  bundler_gem = '-r bundler/setup' if Gem.loaded_specs.keys.include?('bundler')
  libs = '-I ./lib'
  full_cmd = %{ruby #{libs} #{bundler_gem} ./bin/#{cmd}}
  stdout_str, stderr_str = ['', '']
  exit_code = 0
  Open3.popen3(full_cmd) do |stdin, stdout, stderr, wait_thr|
    stdin.write stdin_str
    stdin.close
    stdout_str = stdout.read
    stderr_str = stderr.read
    exit_code = wait_thr.value
  end
  [stdout_str, stderr_str, exit_code]
end

ruby_run("rubyc map -o StringEncoder 'l.upcase'", "tata")