rust-clippy/tests/ui/unnecessary_clone.rs

108 lines
2.6 KiB
Rust

// does not test any rustfixable lints
#![warn(clippy::clone_on_ref_ptr)]
#![allow(unused)]
#![allow(clippy::redundant_clone, clippy::uninlined_format_args, clippy::unnecessary_wraps)]
//@no-rustfix
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 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();
//~^ ERROR: using `.clone()` on a ref-counted pointer
//~| NOTE: `-D clippy::clone-on-ref-ptr` implied by `-D warnings`
Rc::clone(&rc);
arc.clone();
//~^ ERROR: using `.clone()` on a ref-counted pointer
Arc::clone(&arc);
rcweak.clone();
//~^ ERROR: using `.clone()` on a ref-counted pointer
rc::Weak::clone(&rcweak);
arc_weak.clone();
//~^ ERROR: using `.clone()` on a ref-counted pointer
sync::Weak::clone(&arc_weak);
let x = Arc::new(SomeImpl);
let _: Arc<dyn SomeTrait> = x.clone();
//~^ ERROR: using `.clone()` on a ref-counted pointer
}
fn clone_on_copy_generic<T: Copy>(t: T) {
t.clone();
//~^ ERROR: using `clone` on type `T` which implements the `Copy` trait
//~| NOTE: `-D clippy::clone-on-copy` implied by `-D warnings`
Some(t).clone();
//~^ ERROR: using `clone` on type `Option<T>` which implements the `Copy` trait
}
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();
//~^ ERROR: using `clone` on type `E` which implements the `Copy` trait
let _: E = *****a;
}
}
mod issue2076 {
use std::rc::Rc;
macro_rules! try_opt {
($expr: expr) => {
match $expr {
Some(value) => value,
None => return None,
}
};
}
fn func() -> Option<Rc<u8>> {
let rc = Rc::new(42);
Some(try_opt!(Some(rc)).clone())
//~^ ERROR: using `.clone()` on a ref-counted pointer
}
}