rust/tests/ui/suggestions/impl-trait-missing-lifetime...

72 lines
2.5 KiB
Rust

//@ edition:2021
// gate-test-anonymous_lifetime_in_impl_trait
// Verify the behaviour of `feature(anonymous_lifetime_in_impl_trait)`.
mod elided {
fn f(_: impl Iterator<Item = &()>) {}
//~^ ERROR anonymous lifetimes in `impl Trait` are unstable
fn g(mut x: impl Iterator<Item = &()>) -> Option<&()> { x.next() }
//~^ ERROR anonymous lifetimes in `impl Trait` are unstable
//~| ERROR missing lifetime specifier
// Anonymous lifetimes in async fn are already allowed.
// This is understood as `fn foo<'_1>(_: impl Iterator<Item = &'_1 ()>) {}`.
async fn h(_: impl Iterator<Item = &()>) {}
// Anonymous lifetimes in async fn are already allowed.
// But that lifetime does not participate in resolution.
async fn i(mut x: impl Iterator<Item = &()>) -> Option<&()> { x.next() }
//~^ ERROR missing lifetime specifier
//~| ERROR lifetime may not live long enough
}
mod underscore {
fn f(_: impl Iterator<Item = &'_ ()>) {}
//~^ ERROR anonymous lifetimes in `impl Trait` are unstable
fn g(mut x: impl Iterator<Item = &'_ ()>) -> Option<&'_ ()> { x.next() }
//~^ ERROR anonymous lifetimes in `impl Trait` are unstable
//~| ERROR missing lifetime specifier
// Anonymous lifetimes in async fn are already allowed.
// This is understood as `fn foo<'_1>(_: impl Iterator<Item = &'_1 ()>) {}`.
async fn h(_: impl Iterator<Item = &'_ ()>) {}
// Anonymous lifetimes in async fn are already allowed.
// But that lifetime does not participate in resolution.
async fn i(mut x: impl Iterator<Item = &'_ ()>) -> Option<&'_ ()> { x.next() }
//~^ ERROR missing lifetime specifier
//~| ERROR lifetime may not live long enough
}
mod alone_in_path {
trait Foo<'a> { fn next(&mut self) -> Option<&'a ()>; }
fn f(_: impl Foo) {}
//~^ ERROR anonymous lifetimes in `impl Trait` are unstable
fn g(mut x: impl Foo) -> Option<&()> { x.next() }
//~^ ERROR anonymous lifetimes in `impl Trait` are unstable
//~| ERROR missing lifetime specifier
}
mod in_path {
trait Foo<'a, T> { fn next(&mut self) -> Option<&'a T>; }
fn f(_: impl Foo<()>) {}
//~^ ERROR anonymous lifetimes in `impl Trait` are unstable
fn g(mut x: impl Foo<()>) -> Option<&()> { x.next() }
//~^ ERROR anonymous lifetimes in `impl Trait` are unstable
//~| ERROR missing lifetime specifier
}
// This must not err, as the `&` actually resolves to `'a`.
fn resolved_anonymous<'a, T: 'a>(f: impl Fn(&'a str) -> &T) {
//~^ WARNING elided lifetime has a name
f("f");
}
fn main() {}