import pathlib


def volume_bind_args(source, dest):
    """return tuple specifying a source:dest volume bind mount in docker format."""
    # docker run struggle to follow symlinks on mac successfully, see
    # https://github.com/docker/for-mac/issues/1298
    # (and tempfile generates symlinked /var paths...)
    source = pathlib.Path(source).resolve()
    return "-v", f"{source}:{dest}"