83 lines
1.8 KiB
Rust
83 lines
1.8 KiB
Rust
|
#![allow(unused)]
|
||
|
|
#![warn(
|
||
|
|
clippy::all,
|
||
|
|
clippy::style,
|
||
|
|
clippy::mem_replace_option_with_none,
|
||
|
|
clippy::mem_replace_with_default
|
||
|
|
)]
|
||
|
|
#![feature(lang_items)]
|
||
|
|
#![no_std]
|
||
|
|
|
||
|
|
use core::mem;
|
||
|
|
use core::panic::PanicInfo;
|
||
|
|
|
||
|
|
#[lang = "eh_personality"]
|
||
|
|
extern "C" fn eh_personality() {}
|
||
|
|
|
||
|
|
#[panic_handler]
|
||
|
|
fn panic(info: &PanicInfo) -> ! {
|
||
|
|
loop {}
|
||
|
|
}
|
||
|
|
|
||
|
|
fn replace_option_with_none() {
|
||
|
|
let mut an_option = Some(1);
|
||
|
|
let _ = an_option.take();
|
||
|
|
let an_option = &mut Some(1);
|
||
|
|
let _ = an_option.take();
|
||
|
|
}
|
||
|
|
|
||
|
|
fn replace_with_default() {
|
||
|
|
let mut refstr = "hello";
|
||
|
|
let _ = core::mem::take(&mut refstr);
|
||
|
|
|
||
|
|
let mut slice: &[i32] = &[1, 2, 3];
|
||
|
|
let _ = core::mem::take(&mut slice);
|
||
|
|
}
|
||
|
|
|
||
|
|
// lint is disabled for primitives because in this case `take`
|
||
|
|
// has no clear benefit over `replace` and sometimes is harder to read
|
||
|
|
fn dont_lint_primitive() {
|
||
|
|
let mut pbool = true;
|
||
|
|
let _ = mem::replace(&mut pbool, false);
|
||
|
|
|
||
|
|
let mut pint = 5;
|
||
|
|
let _ = mem::replace(&mut pint, 0);
|
||
|
|
}
|
||
|
|
|
||
|
|
fn main() {
|
||
|
|
replace_option_with_none();
|
||
|
|
replace_with_default();
|
||
|
|
dont_lint_primitive();
|
||
|
|
}
|
||
|
|
|
||
|
|
fn issue9824() {
|
||
|
|
struct Foo<'a>(Option<&'a str>);
|
||
|
|
impl<'a> core::ops::Deref for Foo<'a> {
|
||
|
|
type Target = Option<&'a str>;
|
||
|
|
|
||
|
|
fn deref(&self) -> &Self::Target {
|
||
|
|
&self.0
|
||
|
|
}
|
||
|
|
}
|
||
|
|
impl<'a> core::ops::DerefMut for Foo<'a> {
|
||
|
|
fn deref_mut(&mut self) -> &mut Self::Target {
|
||
|
|
&mut self.0
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
struct Bar {
|
||
|
|
opt: Option<u8>,
|
||
|
|
val: u8,
|
||
|
|
}
|
||
|
|
|
||
|
|
let mut f = Foo(Some("foo"));
|
||
|
|
let mut b = Bar { opt: Some(1), val: 12 };
|
||
|
|
|
||
|
|
// replace option with none
|
||
|
|
let _ = f.0.take();
|
||
|
|
let _ = (*f).take();
|
||
|
|
let _ = b.opt.take();
|
||
|
|
// replace with default
|
||
|
|
let _ = mem::replace(&mut b.val, u8::default());
|
||
|
|
}
|