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|
#![feature(fn_traits, unboxed_closures)]
#![warn(clippy::no_effect_underscore_binding)]
#![allow(dead_code, path_statements)]
#![allow(
clippy::deref_addrof,
clippy::redundant_field_names,
clippy::uninlined_format_args,
clippy::unnecessary_struct_initialization,
clippy::useless_vec
)]
use std::fmt::Display;
use std::ops::{Neg, Shl};
struct Cout;
impl<T> Shl<T> for Cout
where
T: Display,
{
type Output = Self;
fn shl(self, rhs: T) -> Self::Output {
println!("{}", rhs);
self
}
}
impl Neg for Cout {
type Output = Self;
fn neg(self) -> Self::Output {
println!("hello world");
self
}
}
struct Unit;
struct Tuple(i32);
struct Struct {
field: i32,
}
enum Enum {
Tuple(i32),
Struct { field: i32 },
}
struct DropUnit;
impl Drop for DropUnit {
fn drop(&mut self) {}
}
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,
}
union Union {
a: u8,
b: f64,
}
fn get_number() -> i32 {
0
}
fn get_struct() -> Struct {
Struct { field: 0 }
}
fn get_drop_struct() -> DropStruct {
DropStruct { field: 0 }
}
unsafe fn unsafe_fn() -> i32 {
0
}
struct GreetStruct1;
impl FnOnce<(&str,)> for GreetStruct1 {
type Output = ();
extern "rust-call" fn call_once(self, (who,): (&str,)) -> Self::Output {
println!("hello {}", who);
}
}
struct GreetStruct2();
impl FnOnce<(&str,)> for GreetStruct2 {
type Output = ();
extern "rust-call" fn call_once(self, (who,): (&str,)) -> Self::Output {
println!("hello {}", who);
}
}
struct GreetStruct3;
impl FnOnce<(&str,)> for GreetStruct3 {
type Output = ();
extern "rust-call" fn call_once(self, (who,): (&str,)) -> Self::Output {
println!("hello {}", who);
}
}
fn main() {
let s = get_struct();
let s2 = get_struct();
0;
//~^ ERROR: statement with no effect
//~| NOTE: `-D clippy::no-effect` implied by `-D warnings`
s2;
//~^ ERROR: statement with no effect
Unit;
//~^ ERROR: statement with no effect
Tuple(0);
//~^ ERROR: statement with no effect
Struct { field: 0 };
//~^ ERROR: statement with no effect
Struct { ..s };
//~^ ERROR: statement with no effect
Union { a: 0 };
//~^ ERROR: statement with no effect
Enum::Tuple(0);
//~^ ERROR: statement with no effect
Enum::Struct { field: 0 };
//~^ ERROR: statement with no effect
5 + 6;
//~^ ERROR: statement with no effect
*&42;
//~^ ERROR: statement with no effect
&6;
//~^ ERROR: statement with no effect
(5, 6, 7);
//~^ ERROR: statement with no effect
..;
//~^ ERROR: statement with no effect
5..;
//~^ ERROR: statement with no effect
..5;
//~^ ERROR: statement with no effect
5..6;
//~^ ERROR: statement with no effect
5..=6;
//~^ ERROR: statement with no effect
[42, 55];
//~^ ERROR: statement with no effect
[42, 55][1];
//~^ ERROR: statement with no effect
(42, 55).1;
//~^ ERROR: statement with no effect
[42; 55];
//~^ ERROR: statement with no effect
[42; 55][13];
//~^ ERROR: statement with no effect
let mut x = 0;
|| x += 5;
//~^ ERROR: statement with no effect
let s: String = "foo".into();
FooString { s: s };
//~^ ERROR: statement with no effect
let _unused = 1;
//~^ ERROR: binding to `_` prefixed variable with no side-effect
//~| NOTE: `-D clippy::no-effect-underscore-binding` implied by `-D warnings`
let _penguin = || println!("Some helpful closure");
//~^ ERROR: binding to `_` prefixed variable with no side-effect
let _duck = Struct { field: 0 };
//~^ ERROR: binding to `_` prefixed variable with no side-effect
let _cat = [2, 4, 6, 8][2];
//~^ ERROR: binding to `_` prefixed variable with no side-effect
#[allow(clippy::no_effect)]
0;
// Do not warn
get_number();
unsafe { unsafe_fn() };
let _used = get_struct();
let _x = vec![1];
DropUnit;
DropStruct { field: 0 };
DropTuple(0);
DropEnum::Tuple(0);
DropEnum::Struct { field: 0 };
GreetStruct1("world");
GreetStruct2()("world");
GreetStruct3 {}("world");
fn n() -> i32 {
42
}
Cout << 142;
-Cout;
}
|
