rust/tests/compile-fail/needless_borrow.rs

35 lines
768 B
Rust

#![feature(plugin)]
#![plugin(clippy)]
fn x(y: &i32) -> i32 {
*y
}
#[deny(clippy)]
#[allow(unused_variables)]
fn main() {
let a = 5;
let b = x(&a);
let c = x(&&a); //~ ERROR: needless_borrow
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`
}
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) {}