mirror of
https://github.com/rust-lang/rust-clippy
synced 2024-11-10 15:14:29 +00:00
141 lines
3.2 KiB
Rust
141 lines
3.2 KiB
Rust
// Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT
|
|
// file at the top-level directory of this distribution.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
|
|
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
|
|
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
|
|
// option. This file may not be copied, modified, or distributed
|
|
// except according to those terms.
|
|
|
|
#![deny(clippy::useless_asref)]
|
|
#![allow(clippy::trivially_copy_pass_by_ref)]
|
|
use std::fmt::Debug;
|
|
|
|
struct FakeAsRef;
|
|
|
|
#[allow(clippy::should_implement_trait)]
|
|
impl FakeAsRef {
|
|
fn as_ref(&self) -> &Self {
|
|
self
|
|
}
|
|
}
|
|
|
|
struct MoreRef;
|
|
|
|
impl<'a, 'b, 'c> AsRef<&'a &'b &'c MoreRef> for MoreRef {
|
|
fn as_ref(&self) -> &&'a &'b &'c MoreRef {
|
|
&&&&MoreRef
|
|
}
|
|
}
|
|
|
|
fn foo_rstr(x: &str) {
|
|
println!("{:?}", x);
|
|
}
|
|
fn foo_rslice(x: &[i32]) {
|
|
println!("{:?}", x);
|
|
}
|
|
fn foo_mrslice(x: &mut [i32]) {
|
|
println!("{:?}", x);
|
|
}
|
|
fn foo_rrrrmr(_: &&&&MoreRef) {
|
|
println!("so many refs");
|
|
}
|
|
|
|
fn not_ok() {
|
|
let rstr: &str = "hello";
|
|
let mut mrslice: &mut [i32] = &mut [1, 2, 3];
|
|
|
|
{
|
|
let rslice: &[i32] = &*mrslice;
|
|
foo_rstr(rstr.as_ref());
|
|
foo_rstr(rstr);
|
|
foo_rslice(rslice.as_ref());
|
|
foo_rslice(rslice);
|
|
}
|
|
{
|
|
foo_mrslice(mrslice.as_mut());
|
|
foo_mrslice(mrslice);
|
|
foo_rslice(mrslice.as_ref());
|
|
foo_rslice(mrslice);
|
|
}
|
|
|
|
{
|
|
let rrrrrstr = &&&&rstr;
|
|
let rrrrrslice = &&&&&*mrslice;
|
|
foo_rslice(rrrrrslice.as_ref());
|
|
foo_rslice(rrrrrslice);
|
|
foo_rstr(rrrrrstr.as_ref());
|
|
foo_rstr(rrrrrstr);
|
|
}
|
|
{
|
|
let mrrrrrslice = &mut &mut &mut &mut mrslice;
|
|
foo_mrslice(mrrrrrslice.as_mut());
|
|
foo_mrslice(mrrrrrslice);
|
|
foo_rslice(mrrrrrslice.as_ref());
|
|
foo_rslice(mrrrrrslice);
|
|
}
|
|
foo_rrrrmr((&&&&MoreRef).as_ref());
|
|
|
|
generic_not_ok(mrslice);
|
|
generic_ok(mrslice);
|
|
}
|
|
|
|
fn ok() {
|
|
let string = "hello".to_owned();
|
|
let mut arr = [1, 2, 3];
|
|
let mut vec = vec![1, 2, 3];
|
|
|
|
{
|
|
foo_rstr(string.as_ref());
|
|
foo_rslice(arr.as_ref());
|
|
foo_rslice(vec.as_ref());
|
|
}
|
|
{
|
|
foo_mrslice(arr.as_mut());
|
|
foo_mrslice(vec.as_mut());
|
|
}
|
|
|
|
{
|
|
let rrrrstring = &&&&string;
|
|
let rrrrarr = &&&&arr;
|
|
let rrrrvec = &&&&vec;
|
|
foo_rstr(rrrrstring.as_ref());
|
|
foo_rslice(rrrrarr.as_ref());
|
|
foo_rslice(rrrrvec.as_ref());
|
|
}
|
|
{
|
|
let mrrrrarr = &mut &mut &mut &mut arr;
|
|
let mrrrrvec = &mut &mut &mut &mut vec;
|
|
foo_mrslice(mrrrrarr.as_mut());
|
|
foo_mrslice(mrrrrvec.as_mut());
|
|
}
|
|
FakeAsRef.as_ref();
|
|
foo_rrrrmr(MoreRef.as_ref());
|
|
|
|
generic_not_ok(arr.as_mut());
|
|
generic_ok(&mut arr);
|
|
}
|
|
|
|
fn foo_mrt<T: Debug + ?Sized>(t: &mut T) {
|
|
println!("{:?}", t);
|
|
}
|
|
fn foo_rt<T: Debug + ?Sized>(t: &T) {
|
|
println!("{:?}", t);
|
|
}
|
|
|
|
fn generic_not_ok<T: AsMut<T> + AsRef<T> + Debug + ?Sized>(mrt: &mut T) {
|
|
foo_mrt(mrt.as_mut());
|
|
foo_mrt(mrt);
|
|
foo_rt(mrt.as_ref());
|
|
foo_rt(mrt);
|
|
}
|
|
|
|
fn generic_ok<U: AsMut<T> + AsRef<T> + ?Sized, T: Debug + ?Sized>(mru: &mut U) {
|
|
foo_mrt(mru.as_mut());
|
|
foo_rt(mru.as_ref());
|
|
}
|
|
|
|
fn main() {
|
|
not_ok();
|
|
ok();
|
|
}
|