You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: realpath.rs
    path of file: ./repos/fish-shell/src/builtins
    
    the code of the file until where you have to start completion: //! Implementation of the realpath builtin.

use errno::errno;

use super::prelude::*;
use crate::env::Environment;
use crate::{
    path::path_apply_working_directory,
    wutil::{normalize_path, wrealpath},
};

#[derive(Default)]
struct Options {
    print_help: bool,
    no_symlinks: bool,
}

const short_options: &wstr = L!("+:hs");
const long_options: &[woption] = &[
    wopt(L!("no-symlinks"), no_argument, 's'),
    wopt(L!("help"), no_argument, 'h'),
];

fn parse_options(
    args: &mut [&wstr],
    parser: &Parser,
    streams: &mut IoStreams,
) -> Result<(Options, usize), Option<c_int>> {
    l
    
pub fn realpath(parser: &Parser, streams: &mut IoStreams, args: &mut [&wstr]) -> Option<c_int> {
    let cmd = args[0];
    let (opts, optind) = match parse_options(args, parser, streams) {
        Ok((opts, optind)) => (opts, optind),
        Err(err @ Some(_)) if err != STATUS_CMD_OK => return err,
        Err(err) => panic!("Illogical exit code from parse_options(): {err:?}"),
    };

    if opts.print_help {
        builtin_print_help(parser, streams, cmd);
        return STATUS_CMD_OK;
    }

    // TODO: allow arbitrary args. `realpath *` should print many paths
    if optind + 1 != args.len() {
        streams.err.append(wgettext_fmt!(
            BUILTIN_ERR_ARG_COUNT1,
            cmd,
            0,
            args.len() - 1
        ));
        builtin_print_help(parser, streams, cmd);
        return STATUS_INVALID_ARGS;
    }

    let arg = args[optind];

    if !opts.no_symlinks {
        if let Some(real_path) = wrealpath(arg) {
            streams.out.append(real_path);
        } else {
            let errno = errno();
            if errno.0 != 0 {
                // realpath() just couldn't do it. Report the error and make it clear
                // this is an error from our builtin, not the system's realpath.
                streams.err.append(wgettext_fmt!(
                    "builtin %ls: %ls: %s\n",
                    cmd,
                    arg,
                    errno.to_string()
                ));
            } else {
                // Who knows. Probably a bug in our wrealpath() implementation.
                streams
                    .err
                    .append(wgettext_fmt!("builtin %ls: Invalid arg: %ls\n", cmd, arg));
            }

            return STATUS_CMD_ERROR;
        }
    } else {
        // We need to get the *physical* pwd here.
        let realpwd = wrealpath(&parser.vars().get_pwd_slash());

        if let Some(realpwd) = realpwd {
            let absolute_arg = if arg.starts_with(L!("/")) {
                arg.to_owned()
            } else {
                path_apply_working_directory(arg, &realpwd)
            };
            streams.out.append(normalize_path(&absolute_arg, false));
        } else {
            streams.err.append(wgettext_fmt!(
                "builtin %ls: realpath failed: %s\n",
                cmd,
                errno().to_string()
            ));
            return STATUS_CMD_ERROR;
        }
    }

    streams.out.append(L!("\n"));

    STATUS_CMD_OK
}