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#![allow(
clippy::deref_addrof,
clippy::no_effect,
clippy::uninlined_format_args,
clippy::unnecessary_struct_initialization,
dead_code,
unused
)]
#![warn(clippy::unnecessary_operation)]
use std::fmt::Display;
use std::ops::Shl;
struct Tuple(i32);
struct Struct {
field: i32,
}
enum Enum {
Tuple(i32),
Struct { field: i32 },
}
struct DropStruct {
field: i32,
}
impl Drop for DropStruct {
fn drop(&mut self) {}
}
struct DropTuple(i32);
impl Drop for DropTuple {
fn drop(&mut self) {}
}
enum DropEnum {
Tuple(i32),
Struct { field: i32 },
}
impl Drop for DropEnum {
fn drop(&mut self) {}
}
struct FooString {
s: String,
}
fn get_number() -> i32 {
0
}
const fn get_usize() -> usize {
0
}
fn get_struct() -> Struct {
Struct { field: 0 }
}
fn get_drop_struct() -> DropStruct {
DropStruct { field: 0 }
}
struct Cout;
impl<T> Shl<T> for Cout
where
T: Display,
{
type Output = Self;
fn shl(self, rhs: T) -> Self::Output {
println!("{}", rhs);
self
}
}
fn main() {
Tuple(get_number());
//~^ unnecessary_operation
Struct { field: get_number() };
//~^ unnecessary_operation
Struct { ..get_struct() };
//~^ unnecessary_operation
Enum::Tuple(get_number());
//~^ unnecessary_operation
Enum::Struct { field: get_number() };
//~^ unnecessary_operation
5 + get_number();
//~^ unnecessary_operation
*&get_number();
//~^ unnecessary_operation
&get_number();
//~^ unnecessary_operation
(5, 6, get_number());
//~^ unnecessary_operation
get_number()..;
//~^ unnecessary_operation
..get_number();
//~^ unnecessary_operation
5..get_number();
//~^ unnecessary_operation
[42, get_number()];
//~^ unnecessary_operation
[42, 55][get_usize()];
//~^ unnecessary_operation
(42, get_number()).1;
//~^ unnecessary_operation
[get_number(); 55];
//~^ unnecessary_operation
[42; 55][get_usize()];
//~^ unnecessary_operation
{
//~^ unnecessary_operation
get_number()
};
FooString {
//~^ unnecessary_operation
s: String::from("blah"),
};
// Do not warn
DropTuple(get_number());
DropStruct { field: get_number() };
DropStruct { field: get_number() };
DropStruct { ..get_drop_struct() };
DropEnum::Tuple(get_number());
DropEnum::Struct { field: get_number() };
// Issue #9954
fn one() -> i8 {
1
}
macro_rules! use_expr {
($($e:expr),*) => {{ $($e;)* }}
}
use_expr!(isize::MIN / -(one() as isize), i8::MIN / -one());
// Issue #11885
Cout << 16;
// Issue #11575
// Bad formatting is required to trigger the bug
#[rustfmt::skip]
'label: {
break 'label
};
let () = const {
[42, 55][get_usize()];
};
}
const _: () = {
[42, 55][get_usize()];
};
const fn foo() {
[42, 55][get_usize()];
//~^ unnecessary_operation
}
fn issue15173() {
// No lint as `Box::new(None)` alone would be ambiguous
Box::new(None) as Box<Option<i32>>;
}
#[expect(clippy::redundant_closure_call)]
fn issue15173_original<MsU>(handler: impl FnOnce() -> MsU + Clone + 'static) {
Box::new(move |value| {
(|_| handler.clone()())(value);
None
}) as Box<dyn Fn(i32) -> Option<i32>>;
}
|
