rust/tests/ui/shadow.rs
Andre Bogus cc622608db new lints around #[must_use] fns
`must_use_unit` lints unit-returning functions with a `#[must_use]`
attribute, suggesting to remove it.

`double_must_use` lints functions with a plain `#[must_use]`
attribute, but which return a type which is already `#[must_use]`,
so the attribute has no benefit.

`must_use_candidate` is a pedantic lint that lints functions and
methods that return some non-unit type that is not already
`#[must_use]` and suggests to add the annotation.
2019-10-14 12:09:04 +02:00

54 lines
898 B
Rust

#![warn(
clippy::all,
clippy::pedantic,
clippy::shadow_same,
clippy::shadow_reuse,
clippy::shadow_unrelated
)]
#![allow(
unused_parens,
unused_variables,
clippy::missing_docs_in_private_items,
clippy::single_match
)]
fn id<T>(x: T) -> T {
x
}
#[must_use]
fn first(x: (isize, isize)) -> isize {
x.0
}
fn main() {
let mut x = 1;
let x = &mut x;
let x = { x };
let x = (&*x);
let x = { *x + 1 };
let x = id(x);
let x = (1, x);
let x = first(x);
let y = 1;
let x = y;
let x;
x = 42;
let o = Some(1_u8);
if let Some(p) = o {
assert_eq!(1, p);
}
match o {
Some(p) => p, // no error, because the p above is in its own scope
None => 0,
};
match (x, o) {
(1, Some(a)) | (a, Some(1)) => (), // no error though `a` appears twice
_ => (),
}
}