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// run-rustfix
// rustfix-only-machine-applicable
use std::ffi::OsString;
use std::path::Path;
fn main() {
let _s = ["lorem", "ipsum"].join(" ");
let s = String::from("foo");
let _s = s;
let s = String::from("foo");
let _s = s;
let s = String::from("foo");
let _s = s;
let _s = Path::new("/a/b/").join("c");
let _s = Path::new("/a/b/").join("c");
let _s = OsString::new();
let _s = OsString::new();
// Check that lint level works
#[allow(clippy::redundant_clone)]
let _s = String::new().to_string();
let tup = (String::from("foo"),);
let _t = tup.0;
let tup_ref = &(String::from("foo"),);
let _s = tup_ref.0.clone(); // this `.clone()` cannot be removed
{
let x = String::new();
let y = &x;
let _x = x.clone(); // ok; `x` is borrowed by `y`
let _ = y.len();
}
let x = (String::new(),);
let _ = Some(String::new()).unwrap_or_else(|| x.0.clone()); // ok; closure borrows `x`
with_branch(Alpha, true);
cannot_double_move(Alpha);
cannot_move_from_type_with_drop();
borrower_propagation();
not_consumed();
issue_5405();
}
#[derive(Clone)]
struct Alpha;
fn with_branch(a: Alpha, b: bool) -> (Alpha, Alpha) {
if b {
(a.clone(), a)
} else {
(Alpha, a)
}
}
fn cannot_double_move(a: Alpha) -> (Alpha, Alpha) {
(a.clone(), a)
}
struct TypeWithDrop {
x: String,
}
impl Drop for TypeWithDrop {
fn drop(&mut self) {}
}
fn cannot_move_from_type_with_drop() -> String {
let s = TypeWithDrop { x: String::new() };
s.x.clone() // removing this `clone()` summons E0509
}
fn borrower_propagation() {
let s = String::new();
let t = String::new();
{
fn b() -> bool {
unimplemented!()
}
let _u = if b() { &s } else { &t };
// ok; `s` and `t` are possibly borrowed
let _s = s.clone();
let _t = t.clone();
}
{
let _u = || s.len();
let _v = [&t; 32];
let _s = s.clone(); // ok
let _t = t.clone(); // ok
}
{
let _u = {
let u = Some(&s);
let _ = s.clone(); // ok
u
};
let _s = s.clone(); // ok
}
{
use std::convert::identity as id;
let _u = id(id(&s));
let _s = s.clone(); // ok, `u` borrows `s`
}
let _s = s;
let _t = t;
#[derive(Clone)]
struct Foo {
x: usize,
}
{
let f = Foo { x: 123 };
let _x = Some(f.x);
let _f = f;
}
{
let f = Foo { x: 123 };
let _x = &f.x;
let _f = f.clone(); // ok
}
}
fn not_consumed() {
let x = std::path::PathBuf::from("home");
let y = x.join("matthias");
// join() creates a new owned PathBuf, does not take a &mut to x variable, thus the .clone() is
// redundant. (It also does not consume the PathBuf)
println!("x: {:?}, y: {:?}", x, y);
let mut s = String::new();
s.clone().push_str("foo"); // OK, removing this `clone()` will change the behavior.
s.push_str("bar");
assert_eq!(s, "bar");
let t = Some(s);
// OK
if let Some(x) = t.clone() {
println!("{}", x);
}
if let Some(x) = t {
println!("{}", x);
}
}
#[allow(clippy::clone_on_copy)]
fn issue_5405() {
let a: [String; 1] = [String::from("foo")];
let _b: String = a[0].clone();
let c: [usize; 2] = [2, 3];
let _d: usize = c[1].clone();
}
|
