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#![allow(unused)]
#![allow(clippy::redundant_clone)]
#![allow(clippy::ptr_arg)] // https://github.com/rust-lang/rust-clippy/issues/10612
#![allow(clippy::needless_late_init)]
#![allow(clippy::box_collection)]
#![warn(clippy::assigning_clones)]
use std::borrow::ToOwned;
use std::ops::{Add, Deref, DerefMut};
// Clone
pub struct HasCloneFrom;
impl Clone for HasCloneFrom {
fn clone(&self) -> Self {
Self
}
fn clone_from(&mut self, source: &Self) {
*self = HasCloneFrom;
}
}
fn clone_method_rhs_val(mut_thing: &mut HasCloneFrom, value_thing: HasCloneFrom) {
mut_thing.clone_from(&value_thing);
}
fn clone_method_rhs_ref(mut_thing: &mut HasCloneFrom, ref_thing: &HasCloneFrom) {
mut_thing.clone_from(ref_thing);
}
fn clone_method_lhs_val(mut mut_thing: HasCloneFrom, ref_thing: &HasCloneFrom) {
mut_thing.clone_from(ref_thing);
}
fn clone_function_lhs_mut_ref(mut_thing: &mut HasCloneFrom, ref_thing: &HasCloneFrom) {
Clone::clone_from(mut_thing, ref_thing);
}
fn clone_function_lhs_val(mut mut_thing: HasCloneFrom, ref_thing: &HasCloneFrom) {
Clone::clone_from(&mut mut_thing, ref_thing);
}
fn clone_function_through_trait(mut_thing: &mut HasCloneFrom, ref_thing: &HasCloneFrom) {
Clone::clone_from(mut_thing, ref_thing);
}
fn clone_function_through_type(mut_thing: &mut HasCloneFrom, ref_thing: &HasCloneFrom) {
Clone::clone_from(mut_thing, ref_thing);
}
fn clone_function_fully_qualified(mut_thing: &mut HasCloneFrom, ref_thing: &HasCloneFrom) {
Clone::clone_from(mut_thing, ref_thing);
}
fn clone_method_lhs_complex(mut_thing: &mut HasCloneFrom, ref_thing: &HasCloneFrom) {
// These parens should be kept as necessary for a receiver
(mut_thing + &mut HasCloneFrom).clone_from(ref_thing);
}
fn clone_method_rhs_complex(mut_thing: &mut HasCloneFrom, ref_thing: &HasCloneFrom) {
// These parens should be removed since they are not needed in a function argument
mut_thing.clone_from(ref_thing + ref_thing);
}
fn clone_method_macro() {
let mut s = String::from("");
s.clone_from(&format!("{} {}", "hello", "world"));
}
fn clone_function_macro() {
let mut s = String::from("");
Clone::clone_from(&mut s, &format!("{} {}", "hello", "world"));
}
fn assign_to_init_mut_var(b: HasCloneFrom) -> HasCloneFrom {
let mut a = HasCloneFrom;
for _ in 1..10 {
a.clone_from(&b);
}
a
}
fn assign_to_late_init_mut_var(b: HasCloneFrom) {
let mut a;
a = HasCloneFrom;
a = b.clone();
}
fn assign_to_uninit_var(b: HasCloneFrom) {
let a;
a = b.clone();
}
fn assign_to_uninit_mut_var(b: HasCloneFrom) {
let mut a;
a = b.clone();
}
fn late_init_let_tuple() {
let (p, q): (String, String);
p = "ghi".to_string();
q = p.clone();
}
#[derive(Clone)]
pub struct HasDeriveClone;
fn ignore_derive_clone(a: &mut HasDeriveClone, b: &HasDeriveClone) {
// Should not be linted, since the Clone impl is derived
*a = b.clone();
}
pub struct HasCloneImpl;
impl Clone for HasCloneImpl {
fn clone(&self) -> Self {
Self
}
}
fn ignore_missing_clone_from(a: &mut HasCloneImpl, b: &HasCloneImpl) {
// Should not be linted, since the Clone impl doesn't override clone_from
*a = b.clone();
}
struct FakeClone;
impl FakeClone {
/// This looks just like `Clone::clone`
fn clone(&self) -> Self {
FakeClone
}
}
fn ignore_fake_clone() {
let mut a = FakeClone;
let b = FakeClone;
// Should not be linted, since the Clone impl doesn't come from std
a = b.clone();
}
fn ignore_generic_clone<T: Clone>(a: &mut T, b: &T) {
// Should not be linted, since we don't know the actual clone impl
*a = b.clone();
}
#[clippy::msrv = "1.62"]
fn msrv_1_62(mut a: String, b: String, c: &str) {
a.clone_from(&b);
// Should not be linted, as clone_into wasn't stabilized until 1.63
a = c.to_owned();
}
#[clippy::msrv = "1.63"]
fn msrv_1_63(mut a: String, b: String, c: &str) {
a.clone_from(&b);
c.clone_into(&mut a);
}
macro_rules! clone_inside {
($a:expr, $b: expr) => {
$a = $b.clone();
};
}
fn clone_inside_macro() {
let mut a = String::new();
let b = String::new();
clone_inside!(a, b);
}
// Make sure that we don't suggest the lint when we call clone inside a Clone impl
// https://github.com/rust-lang/rust-clippy/issues/12600
pub struct AvoidRecursiveCloneFrom;
impl Clone for AvoidRecursiveCloneFrom {
fn clone(&self) -> Self {
Self
}
fn clone_from(&mut self, source: &Self) {
*self = source.clone();
}
}
// ToOwned
fn owned_method_mut_ref(mut_string: &mut String, ref_str: &str) {
ref_str.clone_into(mut_string);
}
fn owned_method_val(mut mut_string: String, ref_str: &str) {
ref_str.clone_into(&mut mut_string);
}
struct HasDeref {
a: String,
}
impl Deref for HasDeref {
type Target = String;
fn deref(&self) -> &Self::Target {
&self.a
}
}
impl DerefMut for HasDeref {
fn deref_mut(&mut self) -> &mut Self::Target {
&mut self.a
}
}
fn owned_method_box(mut_box_string: &mut Box<String>, ref_str: &str) {
ref_str.clone_into(&mut (*mut_box_string));
}
fn owned_method_deref(mut_box_string: &mut HasDeref, ref_str: &str) {
ref_str.clone_into(&mut (*mut_box_string));
}
fn owned_function_mut_ref(mut_thing: &mut String, ref_str: &str) {
ToOwned::clone_into(ref_str, mut_thing);
}
fn owned_function_val(mut mut_thing: String, ref_str: &str) {
ToOwned::clone_into(ref_str, &mut mut_thing);
}
fn owned_method_macro() {
let mut s = String::from("");
format!("{} {}", "hello", "world").clone_into(&mut s);
}
fn owned_function_macro() {
let mut s = String::from("");
ToOwned::clone_into(&format!("{} {}", "hello", "world"), &mut s);
}
struct FakeToOwned;
impl FakeToOwned {
/// This looks just like `ToOwned::to_owned`
fn to_owned(&self) -> Self {
FakeToOwned
}
}
fn fake_to_owned() {
let mut a = FakeToOwned;
let b = FakeToOwned;
// Should not be linted, since the ToOwned impl doesn't come from std
a = b.to_owned();
}
fn main() {}
/// Trait implementation to allow producing a `Thing` with a low-precedence expression.
impl Add for HasCloneFrom {
type Output = Self;
fn add(self, _: HasCloneFrom) -> Self {
self
}
}
/// Trait implementation to allow producing a `&Thing` with a low-precedence expression.
impl<'a> Add for &'a HasCloneFrom {
type Output = Self;
fn add(self, _: &'a HasCloneFrom) -> Self {
self
}
}
/// Trait implementation to allow producing a `&mut Thing` with a low-precedence expression.
impl<'a> Add for &'a mut HasCloneFrom {
type Output = Self;
fn add(self, _: &'a mut HasCloneFrom) -> Self {
self
}
}
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