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// does not test any rustfixable lints
#![warn(clippy::clone_on_ref_ptr)]
#![allow(unused, clippy::redundant_clone)]
use std::cell::RefCell;
use std::rc::{self, Rc};
use std::sync::{self, Arc};
trait SomeTrait {}
struct SomeImpl;
impl SomeTrait for SomeImpl {}
fn main() {}
fn is_ascii(ch: char) -> bool {
ch.is_ascii()
}
fn clone_on_copy() {
42.clone();
vec![1].clone(); // ok, not a Copy type
Some(vec![1]).clone(); // ok, not a Copy type
(&42).clone();
let rc = RefCell::new(0);
rc.borrow().clone();
// Issue #4348
let mut x = 43;
let _ = &x.clone(); // ok, getting a ref
'a'.clone().make_ascii_uppercase(); // ok, clone and then mutate
is_ascii('z'.clone());
// Issue #5436
let mut vec = Vec::new();
vec.push(42.clone());
}
fn clone_on_ref_ptr() {
let rc = Rc::new(true);
let arc = Arc::new(true);
let rcweak = Rc::downgrade(&rc);
let arc_weak = Arc::downgrade(&arc);
rc.clone();
Rc::clone(&rc);
arc.clone();
Arc::clone(&arc);
rcweak.clone();
rc::Weak::clone(&rcweak);
arc_weak.clone();
sync::Weak::clone(&arc_weak);
let x = Arc::new(SomeImpl);
let _: Arc<dyn SomeTrait> = x.clone();
}
fn clone_on_copy_generic<T: Copy>(t: T) {
t.clone();
Some(t).clone();
}
fn clone_on_double_ref() {
let x = vec![1];
let y = &&x;
let z: &Vec<_> = y.clone();
println!("{:p} {:p}", *y, z);
}
mod many_derefs {
struct A;
struct B;
struct C;
struct D;
#[derive(Copy, Clone)]
struct E;
macro_rules! impl_deref {
($src:ident, $dst:ident) => {
impl std::ops::Deref for $src {
type Target = $dst;
fn deref(&self) -> &Self::Target {
&$dst
}
}
};
}
impl_deref!(A, B);
impl_deref!(B, C);
impl_deref!(C, D);
impl std::ops::Deref for D {
type Target = &'static E;
fn deref(&self) -> &Self::Target {
&&E
}
}
fn go1() {
let a = A;
let _: E = a.clone();
let _: E = *****a;
}
fn check(mut encoded: &[u8]) {
let _ = &mut encoded.clone();
let _ = &encoded.clone();
}
}
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