rust/tests/ui/swap.fixed
2021-07-29 15:25:08 +04:30

126 lines
2.1 KiB
Rust

// run-rustfix
#![warn(clippy::all)]
#![allow(
clippy::blacklisted_name,
clippy::no_effect,
clippy::redundant_clone,
redundant_semicolons,
unused_assignments
)]
struct Foo(u32);
#[derive(Clone)]
struct Bar {
a: u32,
b: u32,
}
fn field() {
let mut bar = Bar { a: 1, b: 2 };
let temp = bar.a;
bar.a = bar.b;
bar.b = temp;
let mut baz = vec![bar.clone(), bar.clone()];
let temp = baz[0].a;
baz[0].a = baz[1].a;
baz[1].a = temp;
}
fn array() {
let mut foo = [1, 2];
foo.swap(0, 1);
foo.swap(0, 1);
}
fn slice() {
let foo = &mut [1, 2];
foo.swap(0, 1);
foo.swap(0, 1);
}
fn unswappable_slice() {
let foo = &mut [vec![1, 2], vec![3, 4]];
let temp = foo[0][1];
foo[0][1] = foo[1][0];
foo[1][0] = temp;
// swap(foo[0][1], foo[1][0]) would fail
}
fn vec() {
let mut foo = vec![1, 2];
foo.swap(0, 1);
foo.swap(0, 1);
}
fn xor_swap_locals() {
// This is an xor-based swap of local variables.
let mut a = 0;
let mut b = 1;
std::mem::swap(&mut a, &mut b)
}
fn xor_field_swap() {
// This is an xor-based swap of fields in a struct.
let mut bar = Bar { a: 0, b: 1 };
std::mem::swap(&mut bar.a, &mut bar.b)
}
fn xor_slice_swap() {
// This is an xor-based swap of a slice
let foo = &mut [1, 2];
foo.swap(0, 1)
}
fn xor_no_swap() {
// This is a sequence of xor-assignment statements that doesn't result in a swap.
let mut a = 0;
let mut b = 1;
let mut c = 2;
a ^= b;
b ^= c;
a ^= c;
c ^= a;
}
fn xor_unswappable_slice() {
let foo = &mut [vec![1, 2], vec![3, 4]];
foo[0][1] ^= foo[1][0];
foo[1][0] ^= foo[0][0];
foo[0][1] ^= foo[1][0];
}
#[rustfmt::skip]
fn main() {
field();
array();
slice();
unswappable_slice();
vec();
xor_swap_locals();
xor_field_swap();
xor_slice_swap();
xor_no_swap();
xor_unswappable_slice();
let mut a = 42;
let mut b = 1337;
std::mem::swap(&mut a, &mut b);
; std::mem::swap(&mut a, &mut b);
let mut c = Foo(42);
std::mem::swap(&mut c.0, &mut a);
; std::mem::swap(&mut c.0, &mut a);
}