rust/src/test/ui/generator/auto-trait-regions.rs

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#![feature(generators)]
#![feature(optin_builtin_traits)]
auto trait Foo {}
struct No;
impl !Foo for No {}
struct A<'a, 'b>(&'a mut bool, &'b mut bool, No);
impl<'a, 'b: 'a> Foo for A<'a, 'b> {}
struct OnlyFooIfStaticRef(No);
impl Foo for &'static OnlyFooIfStaticRef {}
struct OnlyFooIfRef(No);
impl<'a> Foo for &'a OnlyFooIfRef {}
fn assert_foo<T: Foo>(f: T) {}
fn main() {
// Make sure 'static is erased for generator interiors so we can't match it in trait selection
let x: &'static _ = &OnlyFooIfStaticRef(No);
let gen = || {
let x = x;
yield;
assert_foo(x);
};
assert_foo(gen);
//~^ ERROR mismatched types
//~| ERROR mismatched types
// Allow impls which matches any lifetime
let x = &OnlyFooIfRef(No);
let gen = || {
let x = x;
yield;
assert_foo(x);
};
assert_foo(gen); // ok
// Disallow impls which relates lifetimes in the generator interior
let gen = || {
let a = A(&mut true, &mut true, No);
yield;
assert_foo(a);
};
assert_foo(gen);
//~^ ERROR E0495
//~| ERROR E0495
}