rust/tests/ui/traits/alias/object-wf.rs

86 lines
1.4 KiB
Rust

//@ check-pass
// This test checks that trait objects involving trait aliases are well-formed.
#![feature(trait_alias)]
trait Obj {}
trait _0 = Send + Sync;
// Just auto traits:
trait _1 = _0 + Send + Sync;
use std::marker::Unpin;
fn _f0() {
let _: Box<dyn _0>;
let _: Box<dyn _1>;
let _: Box<dyn Unpin + _1 + Send + Sync>;
}
// Include object safe traits:
fn _f1() {
let _: Box<dyn Obj + _0>;
let _: Box<dyn Obj + _1>;
let _: Box<dyn Obj + _1 + _0>;
}
// And when the object safe trait is in a trait alias:
trait _2 = Obj;
fn _f2() {
let _: Box<dyn _2 + _0>;
let _: Box<dyn _2 + _1>;
let _: Box<dyn _2 + _1 + _0>;
}
// And it should also work when that trait is has auto traits to the right of it.
trait _3 = Obj + Unpin;
fn _f3() {
let _: Box<dyn _3 + _0>;
let _: Box<dyn _3 + _1>;
let _: Box<dyn _3 + _1 + _0>;
}
// Nest the trait deeply:
trait _4 = _3;
trait _5 = _4 + Sync + _0 + Send;
trait _6 = _5 + Send + _1 + Sync;
fn _f4() {
let _: Box<dyn _6 + _0>;
let _: Box<dyn _6 + _1>;
let _: Box<dyn _6 + _1 + _0>;
}
// Just nest the trait alone:
trait _7 = _2;
trait _8 = _7;
trait _9 = _8;
fn _f5() {
let _: Box<dyn _9>;
}
// First bound is auto trait:
trait _10 = Send + Obj;
trait _11 = Obj + Send;
trait _12 = Sync + _11;
trait _13 = Send + _12;
fn f6() {
let _: Box<dyn _10>;
let _: Box<dyn _13>;
}
fn main() {}