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//@ check-pass
#![feature(rustc_attrs)]
#![allow(unused)]
use std::borrow::Borrow;
use std::ops::Deref;
struct PlainType<T>(T);
#[derive(Clone)]
struct CloneType<T>(T);
fn check(mut encoded: &[u8]) {
let _ = &mut encoded.clone();
//~^ WARN call to `.clone()` on a reference in this situation does nothing
let _ = &encoded.clone();
//~^ WARN call to `.clone()` on a reference in this situation does nothing
}
fn main() {
let non_clone_type_ref = &PlainType(1u32);
let non_clone_type_ref_clone: &PlainType<u32> = non_clone_type_ref.clone();
//~^ WARN call to `.clone()` on a reference in this situation does nothing
let clone_type_ref = &CloneType(1u32);
let clone_type_ref_clone: CloneType<u32> = clone_type_ref.clone();
let non_deref_type = &PlainType(1u32);
let non_deref_type_deref: &PlainType<u32> = non_deref_type.deref();
//~^ WARN call to `.deref()` on a reference in this situation does nothing
let non_borrow_type = &PlainType(1u32);
let non_borrow_type_borrow: &PlainType<u32> = non_borrow_type.borrow();
//~^ WARN call to `.borrow()` on a reference in this situation does nothing
// Borrowing a &&T does not warn since it has collapsed the double reference
let non_borrow_type = &&PlainType(1u32);
let non_borrow_type_borrow: &PlainType<u32> = non_borrow_type.borrow();
}
fn generic<T>(non_clone_type: &PlainType<T>) {
non_clone_type.clone();
//~^ WARN call to `.clone()` on a reference in this situation does nothing
}
fn non_generic(non_clone_type: &PlainType<u32>) {
non_clone_type.clone();
//~^ WARN call to `.clone()` on a reference in this situation does nothing
}
struct DiagnosticClone;
impl Clone for DiagnosticClone {
#[rustc_diagnostic_item = "other_clone"]
fn clone(&self) -> Self {
DiagnosticClone
}
}
fn with_other_diagnostic_item(x: DiagnosticClone) {
x.clone();
}
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