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|
// run-rustfix
#![deny(clippy::useless_asref)]
#![allow(clippy::explicit_auto_deref)]
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);
foo_rstr(rstr);
foo_rslice(rslice);
foo_rslice(rslice);
}
{
foo_mrslice(mrslice);
foo_mrslice(mrslice);
foo_rslice(mrslice);
foo_rslice(mrslice);
}
{
let rrrrrstr = &&&&rstr;
let rrrrrslice = &&&&&*mrslice;
foo_rslice(rrrrrslice);
foo_rslice(rrrrrslice);
foo_rstr(rrrrrstr);
foo_rstr(rrrrrstr);
}
{
let mrrrrrslice = &mut &mut &mut &mut mrslice;
foo_mrslice(mrrrrrslice);
foo_mrslice(mrrrrrslice);
foo_rslice(mrrrrrslice);
foo_rslice(mrrrrrslice);
}
#[allow(unused_parens, clippy::double_parens, clippy::needless_borrow)]
foo_rrrrmr((&&&&MoreRef));
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);
foo_mrt(mrt);
foo_rt(mrt);
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();
}
|
