code: function createReadStream (path) {
    if (typeof path === 'string') {
      return fs.createReadStream(path)
    } else if (Buffer.isBuffer(path)) {
      return path
    } else {
      throw new Error(`Unknown read stream path of type "${typeof path}"`)
    }
  }
docs: Returns a fs.ReadStream or a Buffer, depending on whether the "path" argument is a
  valid file path or whether it's a Buffer object (used for sourceMap when uploadSources
  is set to `true`, because the sourcemap is modified).
  
  @param {string|Buffer} path The path of the file, or the file Buffer
  @returns {fs.ReadStream|Buffer}