rust/tests/ui/impl-trait/equal-hidden-lifetimes.rs
Zhi Qi ce2ae62d68 Convert a hard-warning about named static lifetimes into lint "unused_lifetimes"
Define the `named_static_lifetimes` lint

This lint will replace the existing hard-warning.

Replace the named static lifetime hard-warning with the new lint

Update the UI tests for the `named_static_lifetimes` lint

Remove the direct dependency on `rustc_lint_defs`

fix build

Signed-off-by: Zhi Qi <qizhi@pingcap.com>

use "UNUSED_LIFETIMES" instead

Signed-off-by: Zhi Qi <qizhi@pingcap.com>

update 1 test and fix typo

Signed-off-by: Zhi Qi <qizhi@pingcap.com>

update tests

Signed-off-by: Zhi Qi <qizhi@pingcap.com>

fix tests: add extra blank line

Signed-off-by: Zhi Qi <qizhi@pingcap.com>
2023-02-22 09:44:26 +08:00

49 lines
1.2 KiB
Rust

// Test that we consider equal regions when checking for hidden regions in
// opaque types
// check-pass
// `'a == 'static` so `&'a i32` is fine as the return type
fn equal_regions_static<'a: 'static>(x: &'a i32) -> impl Sized {
x
}
// `'a == 'b` so `&'b i32` is fine as the return type
fn equal_regions<'a: 'b, 'b: 'a>(x: &'b i32) -> impl Sized + 'a {
let y: &'a i32 = x;
let z: &'b i32 = y;
x
}
// `'a == 'b` so `&'a i32` is fine as the return type
fn equal_regions_rev<'a: 'b, 'b: 'a>(x: &'a i32) -> impl Sized + 'b {
let y: &'a i32 = x;
let z: &'b i32 = y;
x
}
// `'a == 'b` so `*mut &'b i32` is fine as the return type
fn equal_regions_inv<'a: 'b, 'b: 'a>(x: *mut &'b i32) -> impl Sized + 'a {
let y: *mut &'a i32 = x;
let z: *mut &'b i32 = y;
x
}
// `'a == 'b` so `*mut &'a i32` is fine as the return type
fn equal_regions_inv_rev<'a: 'b, 'b: 'a>(x: *mut &'a i32) -> impl Sized + 'b {
let y: *mut &'a i32 = x;
let z: *mut &'b i32 = y;
x
}
// Should be able to infer `fn(&'static ())` as the return type.
fn contravariant_lub<'a, 'b: 'a, 'c: 'a, 'd: 'b + 'c>(
x: fn(&'b ()),
y: fn(&'c ()),
c: bool,
) -> impl Sized + 'a {
if c { x } else { y }
}
fn main() {}