Method constructor

src/generic/preload_file.ts:40–59

* Creates a file with the given path and, optionally, the given contents. Note * that, if contents is specified, it will be mutated by the file! * @param _fs The file system that created the file. * @param _path * @param _mode The mode that the file was opened using. * Dictates perm

(_fs: T, _path: string, _flag: FileFlag, _stat: Stats, contents?: Buffer)

   *   specified, we assume it is a new file.
   */
  constructor(_fs: T, _path: string, _flag: FileFlag, _stat: Stats, contents?: Buffer) {
    super();
    this._fs = _fs;
    this._path = _path;
    this._flag = _flag;
    this._stat = _stat;
    if (contents) {
      this._buffer = contents;
    } else {
      // Empty buffer. It'll expand once we write stuff to it.
      this._buffer = emptyBuffer();
    }
    // Note: This invariant is *not* maintained once the file starts getting
    // modified.
    // Note: Only actually matters if file is readable, as writeable modes may
    // truncate/append to file.
    if (this._stat.size !== this._buffer.length && this._flag.isReadable()) {
      throw new Error(`Invalid buffer: Buffer is ${this._buffer.length} long, yet Stats object specifies that file is ${this._stat.size} long.`);
    }
  }

  /**
   * NONSTANDARD: Get the underlying buffer for this file. !!DO NOT MUTATE!! Will mess up dirty tracking.