Do the fish completion

    Parameters
    ----------
    cli : click.Command
        The main click Command of the program
    prog_name : str
        The program name on the command line

    Returns
    -------
    bool
        True if the completion was successful, False otherwise

def do_fish_complete(cli, prog_name):
    """Do the fish completion

    Parameters
    ----------
    cli : click.Command
        The main click Command of the program
    prog_name : str
        The program name on the command line

    Returns
    -------
    bool
        True if the completion was successful, False otherwise
    """
    commandline = os.environ['COMMANDLINE']
    args = split_args(commandline)[1:]
    if args and not commandline.endswith(' '):
        incomplete = args[-1]
        args = args[:-1]
    else:
        incomplete = ''

    for item, help in get_choices(cli, prog_name, args, incomplete):
        if help:
            echo("%s\t%s" % (item, re.sub('\s', ' ', help)))
        else:
            echo(item)

    return True