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|
// run-rustfix
#![feature(lint_reasons)]
#[warn(clippy::all, clippy::needless_borrow)]
#[allow(unused_variables, clippy::unnecessary_mut_passed)]
fn main() {
let a = 5;
let ref_a = &a;
let _ = x(&a); // no warning
let _ = x(&&a); // warn
let mut b = 5;
mut_ref(&mut b); // no warning
mut_ref(&mut &mut b); // warn
let s = &String::from("hi");
let s_ident = f(&s); // should not error, because `&String` implements Copy, but `String` does not
let g_val = g(&Vec::new()); // should not error, because `&Vec<T>` derefs to `&[T]`
let vec = Vec::new();
let vec_val = g(&vec); // should not error, because `&Vec<T>` derefs to `&[T]`
h(&"foo"); // should not error, because the `&&str` is required, due to `&Trait`
let garbl = match 42 {
44 => &a,
45 => {
println!("foo");
&&a
},
46 => &&a,
47 => {
println!("foo");
loop {
println!("{}", a);
if a == 25 {
break &ref_a;
}
}
},
_ => panic!(),
};
let _ = x(&&&a);
let _ = x(&mut &&a);
let _ = x(&&&mut b);
let _ = x(&&ref_a);
{
let b = &mut b;
x(&b);
}
// Issue #8191
let mut x = 5;
let mut x = &mut x;
mut_ref(&mut x);
mut_ref(&mut &mut x);
let y: &mut i32 = &mut x;
let y: &mut i32 = &mut &mut x;
let y = match 0 {
// Don't lint. Removing the borrow would move 'x'
0 => &mut x,
_ => &mut *x,
};
let y: &mut i32 = match 0 {
// Lint here. The type given above triggers auto-borrow.
0 => &mut x,
_ => &mut *x,
};
fn ref_mut_i32(_: &mut i32) {}
ref_mut_i32(match 0 {
// Lint here. The type given above triggers auto-borrow.
0 => &mut x,
_ => &mut *x,
});
// use 'x' after to make sure it's still usable in the fixed code.
*x = 5;
let s = String::new();
// let _ = (&s).len();
// let _ = (&s).capacity();
// let _ = (&&s).capacity();
let x = (1, 2);
let _ = (&x).0;
let x = &x as *const (i32, i32);
let _ = unsafe { (&*x).0 };
// Issue #8367
trait Foo {
fn foo(self);
}
impl Foo for &'_ () {
fn foo(self) {}
}
(&()).foo(); // Don't lint. `()` doesn't implement `Foo`
(&&()).foo();
impl Foo for i32 {
fn foo(self) {}
}
impl Foo for &'_ i32 {
fn foo(self) {}
}
(&5).foo(); // Don't lint. `5` will call `<i32 as Foo>::foo`
(&&5).foo();
trait FooRef {
fn foo_ref(&self);
}
impl FooRef for () {
fn foo_ref(&self) {}
}
impl FooRef for &'_ () {
fn foo_ref(&self) {}
}
(&&()).foo_ref(); // Don't lint. `&()` will call `<() as FooRef>::foo_ref`
struct S;
impl From<S> for u32 {
fn from(s: S) -> Self {
(&s).into()
}
}
impl From<&S> for u32 {
fn from(s: &S) -> Self {
0
}
}
}
#[allow(clippy::needless_borrowed_reference)]
fn x(y: &i32) -> i32 {
*y
}
fn mut_ref(y: &mut i32) {
*y = 5;
}
fn f<T: Copy>(y: &T) -> T {
*y
}
fn g(y: &[u8]) -> u8 {
y[0]
}
trait Trait {}
impl<'a> Trait for &'a str {}
fn h(_: &dyn Trait) {}
#[allow(dead_code)]
fn check_expect_suppression() {
let a = 5;
#[expect(clippy::needless_borrow)]
let _ = x(&&a);
}
#[allow(dead_code)]
mod issue9160 {
pub struct S<F> {
f: F,
}
impl<T, F> S<F>
where
F: Fn() -> T,
{
fn calls_field(&self) -> T {
(&self.f)()
}
}
impl<T, F> S<F>
where
F: FnMut() -> T,
{
fn calls_mut_field(&mut self) -> T {
(&mut self.f)()
}
}
}
|
