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// check-pass
#![allow(unused)]
#![warn(noop_method_call)]
use std::borrow::Borrow;
use std::ops::Deref;
struct PlainType<T>(T);
#[derive(Clone)]
struct CloneType<T>(T);
fn main() {
let non_clone_type_ref = &PlainType(1u32);
let non_clone_type_ref_clone: &PlainType<u32> = non_clone_type_ref.clone();
//~^ WARNING 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 clone_type_ref = &&CloneType(1u32);
let clone_type_ref_clone: &CloneType<u32> = clone_type_ref.clone();
//~^ WARNING using `.clone()` on a double reference, which returns `&CloneType<u32>`
let non_deref_type = &PlainType(1u32);
let non_deref_type_deref: &PlainType<u32> = non_deref_type.deref();
//~^ WARNING call to `.deref()` on a reference in this situation does nothing
let non_deref_type = &&PlainType(1u32);
let non_deref_type_deref: &PlainType<u32> = non_deref_type.deref();
//~^ WARNING using `.deref()` on a double reference, which returns `&PlainType<u32>`
let non_borrow_type = &PlainType(1u32);
let non_borrow_type_borrow: &PlainType<u32> = non_borrow_type.borrow();
//~^ WARNING 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();
let xs = ["a", "b", "c"];
let _v: Vec<&str> = xs.iter().map(|x| x.clone()).collect(); // could use `*x` instead
//~^ WARNING using `.clone()` on a double reference, which returns `&str`
}
fn generic<T>(non_clone_type: &PlainType<T>) {
non_clone_type.clone();
//~^ WARNING call to `.clone()` on a reference in this situation does nothing
}
fn non_generic(non_clone_type: &PlainType<u32>) {
non_clone_type.clone();
//~^ WARNING call to `.clone()` on a reference in this situation does nothing
}
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