def METHOD_NAME(tmp_path):
    """Create a temporary FFL file structure and mock it into
    the test environment.
    """
    for path, lines in FFLS.items():
        ffl = tmp_path / path
        ffl.write_text("\n".join(lines))
    with mock.patch.dict(
        "os.environ",
        {"FFLPATH": str(tmp_path)},
        clear=True,
    ):
        yield