docs: def fetch_local_files(destination_directory: str,
                        verbose: bool) -> prepared_env.PreparedEnv:
      """Uses local files to create a directory for testing and comparisons.
  
      Args:
          destination_directory: The directory where the copied files should go.
          verbose: When set, more progress output is produced.
  
      Returns:
          Commit ids corresponding to content to test/compare.
      """
      staging_dir = destination_directory + '-staging'
      try:
          shutil.copytree(get_repo_root(), staging_dir)
          os.chdir(staging_dir)
          if verbose:
              print('chdir', staging_dir, file=sys.stderr)
  
          shell_tools.run_cmd(
              'git',
              'add',
              '--all',
              out=sys.stderr,
              log_run_to_stderr=verbose)
  
          shell_tools.run_cmd(
              'git',
              'commit',
              '-m', 'working changes',
              '--allow-empty',
              '--no-gpg-sign',
              None if verbose else '--quiet',
              out=sys.stderr,
              log_run_to_stderr=verbose)
  
          cur_commit = shell_tools.output_of('git', 'rev-parse', 'HEAD')
  
          os.chdir(destination_directory)
          if verbose:
              print('chdir', destination_directory, file=sys.stderr)
          shell_tools.run_cmd('git',
                              'init',
                              None if verbose else '--quiet',
                              out=sys.stderr,
                              log_run_to_stderr=verbose)
          result = _git_fetch_for_comparison(staging_dir,
                                             cur_commit,
                                             'master',
                                             verbose=verbose)
      finally:
          shutil.rmtree(staging_dir, ignore_errors=True)
  
      shell_tools.run_cmd(
          'git',
          'branch',
          None if verbose else '--quiet',
          'compare_commit',
          result.compare_commit_id,
          log_run_to_stderr=verbose)
      shell_tools.run_cmd(
          'git',
          'checkout',
          None if verbose else '--quiet',
          '-b',
          'actual_commit',
          result.actual_commit_id,
          log_run_to_stderr=verbose)
      return prepared_env.PreparedEnv(
          github_repo=None,
          actual_commit_id=result.actual_commit_id,
          compare_commit_id=result.compare_commit_id,
          destination_directory=destination_directory,
          virtual_env_path=None)