module Cucumber::CiEnvironment

def detect_revision(ci_environment, env, file_reader)
  if env['GITHUB_EVENT_NAME'] == 'pull_request'
    raise StandardError('GITHUB_EVENT_PATH not set') unless env['GITHUB_EVENT_PATH']
    event = JSON.parse(file_reader.call(env['GITHUB_EVENT_PATH']))
    raise StandardError("No after property in #{env['GITHUB_EVENT_PATH']}:\n#{JSON.pretty_generate(event)}") unless event['after']
    return event['after']
  end
  return evaluate(ci_environment['git']['revision'], env)
end