rust/tests/ui/needless_borrow.rs

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#![feature(plugin)]
#![plugin(clippy)]
fn x(y: &i32) -> i32 {
*y
}
#[warn(clippy)]
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#[allow(unused_variables)]
fn main() {
let a = 5;
let b = x(&a);
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let c = x(&&a);
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let s = &String::from("hi");
let s_ident = f(&s); // should not error, because `&String` implements Copy, but `String` does not
let g_val = g(&Vec::new()); // should not error, because `&Vec<T>` derefs to `&[T]`
let vec = Vec::new();
let vec_val = g(&vec); // should not error, because `&Vec<T>` derefs to `&[T]`
h(&"foo"); // should not error, because the `&&str` is required, due to `&Trait`
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if let Some(ref cake) = Some(&5) {}
let garbl = match 42 {
44 => &a,
45 => {
println!("foo");
&&a // FIXME: this should lint, too
},
46 => &&a,
_ => panic!(),
};
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}
fn f<T:Copy>(y: &T) -> T {
*y
}
fn g(y: &[u8]) -> u8 {
y[0]
}
trait Trait {}
impl<'a> Trait for &'a str {}
fn h(_: &Trait) {}
#[allow(dead_code)]
fn issue_1432() {
let mut v = Vec::<String>::new();
let _ = v.iter_mut().filter(|&ref a| a.is_empty());
let _ = v.iter().filter(|&ref a| a.is_empty());
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let _ = v.iter().filter(|&a| a.is_empty());
}