def scan_config_argument(ctx, param, value, config_dir=None):
    """Validate / translate config name/path values for click config arg.

    Wrapper on top of :func:`cli.scan_config`."""
    if callable(config_dir):
        config_dir = config_dir()

    if not config:
        click.echo("Enter at least one CONFIG")
        click.echo(ctx.get_help(), color=ctx.color)
        ctx.exit()

    if isinstance(value, string_types):
        value = scan_config(value, config_dir=config_dir)

    elif isinstance(value, tuple):
        value = tuple([scan_config(v, config_dir=config_dir) for v in value])

    return value
Validate / translate config name/path values for click config arg.

    Wrapper on top of :func:`cli.scan_config`.