docs: function setup (request, options, ...args) {
    const len = request.headers['content-length']
    const encoding = request.headers['content-encoding'] || 'identity'
    return Object.assign({}, options, {
      encoding: options.encoding || 'utf-8',
      limit: options.limit || '1mb',
      length: (len && encoding === 'identity') ? ~~len : options.length
    }, ...args)
  }