tests/ui/trait-bounds/more_maybe_bounds.rs


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// FIXME(more_maybe_bounds): Even under `more_maybe_bounds` / `-Zexperimental-default-bounds`,
// trying to relax non-default bounds should still be an error in all contexts! As you can see
// there are places like supertrait bounds and trait object types where we currently don't perform
// this check.
#![feature(auto_traits, more_maybe_bounds, negative_impls)]

trait Trait1 {}
auto trait Trait2 {}

// FIXME: `?Trait1` should be rejected, `Trait1` isn't marked `#[lang = "default_traitN"]`.
trait Trait3: ?Trait1 {}
trait Trait4 where Self: Trait1 {}

// FIXME: `?Trait2` should be rejected, `Trait2` isn't marked `#[lang = "default_traitN"]`.
fn foo(_: Box<(dyn Trait3 + ?Trait2)>) {}
fn bar<T: ?Sized + ?Trait2 + ?Trait1 + ?Trait4>(_: &T) {}
//~^ ERROR bound modifier `?` can only be applied to default traits like `Sized`
//~| ERROR bound modifier `?` can only be applied to default traits like `Sized`
//~| ERROR bound modifier `?` can only be applied to default traits like `Sized`

struct S;
impl !Trait2 for S {}
impl Trait1 for S {}
impl Trait3 for S {}

fn main() {
    foo(Box::new(S));
    bar(&S);
}