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.

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)