Find dominating file name

find_dominating.py

def find_dominating(filename: str, start_path: Path):
    """Look for `filename` in `start_path` or any of its ancestor directories.
    
    Args:
        filename: The filename to look for
        start_path: The directory in which to start the search
    
    Returns: The dominating path
    
    Raises:
        FileNotFoundError: The dominating directory is not found.
    """
    path = start_path.absolute()
    if path.is_file():
        path = path.parent

    while True:
        if (path / filename).exists():
            return path
        if path == path.parent:
            break
        path = path.parent

    raise FileNotFoundError(
        f'No file named "{filename}" dominating {start_path}')