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|
#![warn(clippy::map_clone)]
#![allow(
clippy::clone_on_copy,
clippy::iter_cloned_collect,
clippy::many_single_char_names,
clippy::redundant_clone,
clippy::redundant_closure,
clippy::useless_asref,
clippy::useless_vec
)]
fn main() {
let _: Vec<i8> = vec![5_i8; 6].iter().copied().collect();
let _: Vec<String> = vec![String::new()].iter().cloned().collect();
let _: Vec<u32> = vec![42, 43].iter().copied().collect();
let _: Option<u64> = Some(Box::new(16)).map(|b| *b);
let _: Option<u64> = Some(&16).copied();
let _: Option<u8> = Some(&1).copied();
// Don't lint these
let v = vec![5_i8; 6];
let a = 0;
let b = &a;
let _ = v.iter().map(|_x| *b);
let _ = v.iter().map(|_x| a.clone());
let _ = v.iter().map(|&_x| a);
// Issue #498
let _ = std::env::args();
// Issue #4824 item types that aren't references
{
use std::rc::Rc;
let o: Option<Rc<u32>> = Some(Rc::new(0_u32));
let _: Option<u32> = o.map(|x| *x);
let v: Vec<Rc<u32>> = vec![Rc::new(0_u32)];
let _: Vec<u32> = v.into_iter().map(|x| *x).collect();
}
// Issue #5524 mutable references
{
let mut c = 42;
let v = vec![&mut c];
let _: Vec<u32> = v.into_iter().map(|x| *x).collect();
let mut d = 21;
let v = vec![&mut d];
let _: Vec<u32> = v.into_iter().map(|&mut x| x).collect();
}
// Issue #6299
{
let mut aa = 5;
let mut bb = 3;
let items = vec![&mut aa, &mut bb];
let _: Vec<_> = items.into_iter().map(|x| x.clone()).collect();
}
// Issue #6239 deref coercion and clone deref
{
use std::cell::RefCell;
let _ = Some(RefCell::new(String::new()).borrow()).map(|s| s.clone());
}
let x = Some(String::new());
let x = x.as_ref(); // We do this to prevent triggering the `useless_asref` lint.
let y = x.cloned();
//~^ ERROR: you are explicitly cloning with `.map()`
let y = x.cloned();
//~^ ERROR: you are explicitly cloning with `.map()`
//~| HELP: consider calling the dedicated `cloned` method
let y = x.cloned();
//~^ ERROR: you are explicitly cloning with `.map()`
//~| HELP: consider calling the dedicated `cloned` method
let x: Option<u32> = Some(0);
let x = x.as_ref(); // We do this to prevent triggering the `useless_asref` lint.
let y = x.copied();
//~^ ERROR: you are explicitly cloning with `.map()`
//~| HELP: consider calling the dedicated `copied` method
let y = x.copied();
//~^ ERROR: you are explicitly cloning with `.map()`
//~| HELP: consider calling the dedicated `copied` method
// Should not suggest `copied` or `cloned` here since `T` is not a reference.
let x: Option<u32> = Some(0);
let y = x.map(|x| u32::clone(&x));
let y = x.map(|x| Clone::clone(&x));
// Testing with `Result` now.
let x: Result<String, ()> = Ok(String::new());
let x = x.as_ref(); // We do this to prevent triggering the `useless_asref` lint.
let y = x.cloned();
//~^ ERROR: you are explicitly cloning with `.map()`
//~| HELP: consider calling the dedicated `cloned` method
let y = x.cloned();
//~^ ERROR: you are explicitly cloning with `.map()`
//~| HELP: consider calling the dedicated `cloned` method
let x: Result<u32, ()> = Ok(0);
let x = x.as_ref(); // We do this to prevent triggering the `useless_asref` lint.
let y = x.copied();
//~^ ERROR: you are explicitly cloning with `.map()`
//~| HELP: consider calling the dedicated `copied` method
let y = x.copied();
//~^ ERROR: you are explicitly cloning with `.map()`
//~| HELP: consider calling the dedicated `copied` method
// Should not suggest `copied` or `cloned` here since `T` is not a reference.
let x: Result<u32, ()> = Ok(0);
let y = x.map(|x| u32::clone(&x));
let y = x.map(|x| Clone::clone(&x));
// We ensure that no warning is emitted here because `useless_asref` is taking over.
let x = Some(String::new());
let y = x.as_ref().map(|x| String::clone(x));
let x: Result<String, ()> = Ok(String::new());
let y = x.as_ref().map(|x| String::clone(x));
}
|
