rust/tests/ui/temporary_assignment.rs

77 lines
1.6 KiB
Rust

#![warn(clippy::temporary_assignment)]
#![allow(clippy::needless_lifetimes)]
use std::ops::{Deref, DerefMut};
struct TupleStruct(i32);
struct Struct {
field: i32,
}
struct MultiStruct {
structure: Struct,
}
struct Wrapper<'a> {
inner: &'a mut Struct,
}
impl<'a> Deref for Wrapper<'a> {
type Target = Struct;
fn deref(&self) -> &Struct {
self.inner
}
}
impl<'a> DerefMut for Wrapper<'a> {
fn deref_mut(&mut self) -> &mut Struct {
self.inner
}
}
struct ArrayStruct {
array: [i32; 1],
}
const A: TupleStruct = TupleStruct(1);
const B: Struct = Struct { field: 1 };
const C: MultiStruct = MultiStruct {
structure: Struct { field: 1 },
};
const D: ArrayStruct = ArrayStruct { array: [1] };
fn main() {
let mut s = Struct { field: 0 };
let mut t = (0, 0);
Struct { field: 0 }.field = 1;
//~^ ERROR: assignment to temporary
//~| NOTE: `-D clippy::temporary-assignment` implied by `-D warnings`
MultiStruct {
//~^ ERROR: assignment to temporary
structure: Struct { field: 0 },
}
.structure
.field = 1;
ArrayStruct { array: [0] }.array[0] = 1;
//~^ ERROR: assignment to temporary
(0, 0).0 = 1;
//~^ ERROR: assignment to temporary
// no error
s.field = 1;
t.0 = 1;
Wrapper { inner: &mut s }.field = 1;
let mut a_mut = TupleStruct(1);
a_mut.0 = 2;
let mut b_mut = Struct { field: 1 };
b_mut.field = 2;
let mut c_mut = MultiStruct {
structure: Struct { field: 1 },
};
c_mut.structure.field = 2;
let mut d_mut = ArrayStruct { array: [1] };
d_mut.array[0] = 2;
}