rust/tests/ui/lint/dead-code/no-dead-code-for-static-tra...

62 lines
1.6 KiB
Rust

//! Regression test to ensure false positive `dead_code` diagnostic warnings are not triggered for
//! structs and enums that implement static trait functions or use associated constants.
//!
//! Aliased versions of all cases are also tested
//!
//! Issue: <https://github.com/rust-lang/rust/issues/23808>
//@ check-pass
#![deny(dead_code)]
trait Const {
const C: ();
}
trait StaticFn {
fn sfn();
}
macro_rules! impl_const {($($T:ident),*) => {$(
impl Const for $T {
const C: () = ();
}
)*}}
macro_rules! impl_static_fn {($($T:ident),*) => {$(
impl StaticFn for $T {
fn sfn() {}
}
)*}}
struct ConstStruct;
enum ConstEnum {}
struct AliasedConstStruct;
type AliasConstStruct = AliasedConstStruct;
enum AliasedConstEnum {}
type AliasConstEnum = AliasedConstEnum;
impl_const!(ConstStruct, ConstEnum, AliasedConstStruct, AliasedConstEnum);
struct StaticFnStruct;
enum StaticFnEnum {}
struct AliasedStaticFnStruct;
type AliasStaticFnStruct = AliasedStaticFnStruct;
enum AliasedStaticFnEnum {}
type AliasStaticFnEnum = AliasedStaticFnEnum;
impl_static_fn!(StaticFnStruct, StaticFnEnum, AliasedStaticFnStruct, AliasedStaticFnEnum);
fn main() {
// Use the associated constant for all the types, they should be considered "used"
let () = ConstStruct::C;
let () = ConstEnum::C;
let () = AliasConstStruct::C;
let () = AliasConstEnum::C;
// Use the associated static function for all the types, they should be considered "used"
StaticFnStruct::sfn();
StaticFnEnum::sfn();
AliasStaticFnStruct::sfn();
AliasStaticFnEnum::sfn();
}