}
          });
    }
  }

  private Path createTempFile() throws IOException {
    return Files.createTempFile(tempDir, "test", ".test");
  }

  public void testByteSource_size_ofDirectory() throws IOException {
    try (FileSystem fs = Jimfs.newFileSystem(Configuration.unix())) {
      Path dir = fs.getPath("dir");
      Files.createDirectory(dir);