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#![allow(unused)]
#![warn(clippy::match_as_ref)]
fn match_as_ref() {
let owned: Option<()> = None;
let borrowed: Option<&()> = match owned {
//~^ match_as_ref
None => None,
Some(ref v) => Some(v),
};
let mut mut_owned: Option<()> = None;
let borrow_mut: Option<&mut ()> = match mut_owned {
//~^ match_as_ref
None => None,
Some(ref mut v) => Some(v),
};
}
mod issue4437 {
use std::error::Error;
use std::fmt;
use std::num::ParseIntError;
#[derive(Debug)]
struct E {
source: Option<ParseIntError>,
}
impl Error for E {
fn source(&self) -> Option<&(dyn Error + 'static)> {
match self.source {
//~^ match_as_ref
Some(ref s) => Some(s),
None => None,
}
}
}
impl fmt::Display for E {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
unimplemented!()
}
}
}
fn main() {
// Don't lint
let _ = match Some(0) {
#[cfg(feature = "foo")]
Some(ref x) if *x > 50 => None,
Some(ref x) => Some(x),
None => None,
};
}
mod issue15691 {
use std::ops::{Deref, DerefMut};
struct A(B);
struct B;
impl Deref for A {
type Target = B;
fn deref(&self) -> &Self::Target {
&self.0
}
}
impl DerefMut for A {
fn deref_mut(&mut self) -> &mut Self::Target {
&mut self.0
}
}
fn func() {
let mut a = Some(A(B));
let mut b = Some(B);
// Do not lint, we don't have `None => None`
let _ = match b {
Some(ref mut x) => Some(x),
None => a.as_deref_mut(),
};
}
}
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