#![allow(unused, clippy::redundant_clone, clippy::useless_vec)]
#![warn(clippy::option_as_ref_deref)]

use std::ffi::{CString, OsString};
use std::ops::{Deref, DerefMut};
use std::path::PathBuf;

fn main() {
    let mut opt = Some(String::from("123"));

    let _ = opt.clone().as_deref().map(str::len);

    #[rustfmt::skip]
    let _ = opt.clone().as_deref()
        .map(str::len);

    let _ = opt.as_deref_mut();

    let _ = opt.as_deref();
    let _ = opt.as_deref();
    let _ = opt.as_deref_mut();
    let _ = opt.as_deref_mut();
    let _ = Some(CString::new(vec![]).unwrap()).as_deref();
    let _ = Some(OsString::new()).as_deref();
    let _ = Some(PathBuf::new()).as_deref();
    let _ = Some(Vec::<()>::new()).as_deref();
    let _ = Some(Vec::<()>::new()).as_deref_mut();

    let _ = opt.as_deref();
    let _ = opt.clone().as_deref_mut().map(|x| x.len());

    let vc = vec![String::new()];
    let _ = Some(1_usize).as_ref().map(|x| vc[*x].as_str()); // should not be linted

    let _: Option<&str> = Some(&String::new()).as_ref().map(|x| x.as_str()); // should not be linted

    let _ = opt.as_deref();
    let _ = opt.as_deref_mut();

    // Issue #5927
    let _ = opt.as_deref();
}

#[clippy::msrv = "1.39"]
fn msrv_1_39() {
    let opt = Some(String::from("123"));
    let _ = opt.as_ref().map(String::as_str);
}

#[clippy::msrv = "1.40"]
fn msrv_1_40() {
    let opt = Some(String::from("123"));
    let _ = opt.as_deref();
}