rust-clippy/tests/ui/mut_reference.rs

60 lines
1.6 KiB
Rust

#![allow(unused_variables, dead_code)]
//@no-rustfix
fn takes_an_immutable_reference(a: &i32) {}
fn takes_a_mutable_reference(a: &mut i32) {}
mod issue11268 {
macro_rules! x {
($f:expr) => {
$f(&mut 1);
};
}
fn f() {
x!(super::takes_an_immutable_reference);
x!(super::takes_a_mutable_reference);
}
}
struct MyStruct;
impl MyStruct {
fn takes_an_immutable_reference(&self, a: &i32) {}
fn takes_a_mutable_reference(&self, a: &mut i32) {}
}
#[warn(clippy::unnecessary_mut_passed)]
fn main() {
// Functions
takes_an_immutable_reference(&mut 42);
//~^ ERROR: the function `takes_an_immutable_reference` doesn't need a mutable referen
//~| NOTE: `-D clippy::unnecessary-mut-passed` implied by `-D warnings`
let as_ptr: fn(&i32) = takes_an_immutable_reference;
as_ptr(&mut 42);
//~^ ERROR: the function `as_ptr` doesn't need a mutable reference
// Methods
let my_struct = MyStruct;
my_struct.takes_an_immutable_reference(&mut 42);
//~^ ERROR: the method `takes_an_immutable_reference` doesn't need a mutable reference
// No error
// Functions
takes_an_immutable_reference(&42);
let as_ptr: fn(&i32) = takes_an_immutable_reference;
as_ptr(&42);
takes_a_mutable_reference(&mut 42);
let as_ptr: fn(&mut i32) = takes_a_mutable_reference;
as_ptr(&mut 42);
let a = &mut 42;
takes_an_immutable_reference(a);
// Methods
my_struct.takes_an_immutable_reference(&42);
my_struct.takes_a_mutable_reference(&mut 42);
my_struct.takes_an_immutable_reference(a);
}