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//@run-rustfix
#![allow(unused, clippy::redundant_clone, clippy::derive_partial_eq_without_eq)] // See #5700
// Define the types in each module to avoid trait impls leaking between modules.
macro_rules! impl_types {
() => {
#[derive(PartialEq)]
pub struct Owned;
pub struct Borrowed;
impl ToOwned for Borrowed {
type Owned = Owned;
fn to_owned(&self) -> Owned {
Owned {}
}
}
impl std::borrow::Borrow<Borrowed> for Owned {
fn borrow(&self) -> &Borrowed {
static VALUE: Borrowed = Borrowed {};
&VALUE
}
}
};
}
// Only Borrowed == Owned is implemented
mod borrowed_eq_owned {
impl_types!();
impl PartialEq<Owned> for Borrowed {
fn eq(&self, _: &Owned) -> bool {
true
}
}
pub fn compare() {
let owned = Owned {};
let borrowed = Borrowed {};
if borrowed.to_owned() == owned {}
if owned == borrowed.to_owned() {}
}
}
// Only Owned == Borrowed is implemented
mod owned_eq_borrowed {
impl_types!();
impl PartialEq<Borrowed> for Owned {
fn eq(&self, _: &Borrowed) -> bool {
true
}
}
fn compare() {
let owned = Owned {};
let borrowed = Borrowed {};
if owned == borrowed.to_owned() {}
if borrowed.to_owned() == owned {}
}
}
mod issue_4874 {
impl_types!();
// NOTE: PartialEq<Borrowed> for T can't be implemented due to the orphan rules
impl<T> PartialEq<T> for Borrowed
where
T: AsRef<str> + ?Sized,
{
fn eq(&self, _: &T) -> bool {
true
}
}
impl std::fmt::Display for Borrowed {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "borrowed")
}
}
fn compare() {
let borrowed = Borrowed {};
if "Hi" == borrowed.to_string() {}
if borrowed.to_string() == "Hi" {}
}
}
fn main() {}
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