rust/tests/ui/map_identity.rs
2023-10-21 15:40:34 +02:00

56 lines
1.8 KiB
Rust

#![warn(clippy::map_identity)]
#![allow(clippy::needless_return)]
fn main() {
let x: [u16; 3] = [1, 2, 3];
// should lint
let _: Vec<_> = x.iter().map(not_identity).map(|x| return x).collect();
let _: Vec<_> = x.iter().map(std::convert::identity).map(|y| y).collect();
let _: Option<u8> = Some(3).map(|x| x);
let _: Result<i8, f32> = Ok(-3).map(|x| {
return x;
});
// should not lint
let _: Vec<_> = x.iter().map(|x| 2 * x).collect();
let _: Vec<_> = x.iter().map(not_identity).map(|x| return x - 4).collect();
let _: Option<u8> = None.map(|x: u8| x - 1);
let _: Result<i8, f32> = Err(2.3).map(|x: i8| {
return x + 3;
});
let _: Result<u32, u32> = Ok(1).map_err(|a| a);
let _: Result<u32, u32> = Ok(1).map_err(|a: u32| a * 42);
// : u32 guides type inference
let _ = Ok(1).map_err(|a: u32| a);
let _ = Ok(1).map_err(std::convert::identity::<u32>);
}
fn issue7189() {
// should lint
let x = [(1, 2), (3, 4)];
let _ = x.iter().map(|(x, y)| (x, y));
let _ = x.iter().map(|(x, y)| {
return (x, y);
});
let _ = x.iter().map(|(x, y)| return (x, y));
let y = [(1, 2, (3, (4,))), (5, 6, (7, (8,)))];
let _ = y.iter().map(|(x, y, (z, (w,)))| (x, y, (z, (w,))));
// should not lint
let _ = x.iter().map(|(x, y)| (x, y, y));
let _ = x.iter().map(|(x, _y)| (x,));
let _ = x.iter().map(|(x, _)| (x,));
let _ = x.iter().map(|(x, ..)| (x,));
let _ = y.iter().map(|(x, y, (z, _))| (x, y, (z, z)));
let _ = y
.iter()
.map(|(x, y, (z, _)): &(i32, i32, (i32, (i32,)))| (x, y, (z, z)));
let _ = y
.iter()
.map(|(x, y, (z, (w,))): &(i32, i32, (i32, (i32,)))| (x, y, (z, (w,))));
}
fn not_identity(x: &u16) -> u16 {
*x
}