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#![warn(clippy::needless_as_bytes)]
#![allow(clippy::const_is_empty)]
#![feature(exact_size_is_empty)]
struct S;
impl S {
fn as_bytes(&self) -> &[u8] {
&[]
}
fn bytes(&self) -> &[u8] {
&[]
}
}
fn main() {
if "some string".is_empty() {
//~^ needless_as_bytes
println!("len = {}", "some string".len());
//~^ needless_as_bytes
}
if "some string".is_empty() {
//~^ needless_as_bytes
println!("len = {}", "some string".len());
//~^ needless_as_bytes
}
let s = String::from("yet another string");
if s.is_empty() {
//~^ needless_as_bytes
println!("len = {}", s.len());
//~^ needless_as_bytes
}
if s.is_empty() {
//~^ needless_as_bytes
println!("len = {}", s.len());
//~^ needless_as_bytes
}
// Do not lint
let _ = S.as_bytes().is_empty();
let _ = S.as_bytes().len();
let _ = (&String::new() as &dyn AsBytes).as_bytes().len();
macro_rules! m {
(1) => {
""
};
(2) => {
"".as_bytes()
};
}
m!(1).as_bytes().len();
let _ = S.bytes().is_empty();
let _ = S.bytes().len();
let _ = (&String::new() as &dyn Bytes).bytes().len();
macro_rules! m {
(1) => {
""
};
(2) => {
"".bytes()
};
}
m!(1).bytes().len();
m!(2).len();
}
pub trait AsBytes {
fn as_bytes(&self) -> &[u8];
}
impl AsBytes for String {
fn as_bytes(&self) -> &[u8] {
&[]
}
}
pub trait Bytes {
fn bytes(&self) -> &[u8];
}
impl Bytes for String {
fn bytes(&self) -> &[u8] {
&[]
}
}
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