diff options
Diffstat (limited to 'src/test/ui/type-alias-impl-trait/closure_parent_substs.rs')
-rw-r--r-- | src/test/ui/type-alias-impl-trait/closure_parent_substs.rs | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/src/test/ui/type-alias-impl-trait/closure_parent_substs.rs b/src/test/ui/type-alias-impl-trait/closure_parent_substs.rs new file mode 100644 index 000000000..475f4724f --- /dev/null +++ b/src/test/ui/type-alias-impl-trait/closure_parent_substs.rs @@ -0,0 +1,65 @@ +// When WF checking the hidden type in the ParamEnv of the opaque type, +// one complication arises when the hidden type is a closure/generator: +// the "parent_substs" of the type may reference lifetime parameters +// not present in the opaque type. +// These region parameters are not really useful in this check. +// So here we ignore them and replace them with fresh region variables. + +// check-pass + +#![feature(type_alias_impl_trait)] +#![allow(dead_code)] + +// Basic test +mod test1 { + // Hidden type = Closure['_#0r] + type Opaque = impl Sized; + + fn define<'a: 'a>() -> Opaque { + || {} + } +} + +// the region vars cannot both be equal to `'static` or `'empty` +mod test2 { + trait Trait {} + + // Hidden type = Closure['a, '_#0r, '_#1r] + // Constraints = [('_#0r: 'a), ('a: '_#1r)] + type Opaque<'a> + where + &'a (): Trait, + = impl Sized + 'a; + + fn define<'a, 'x, 'y>() -> Opaque<'a> + where + &'a (): Trait, + 'x: 'a, + 'a: 'y, + { + || {} + } +} + +// the region var cannot be equal to `'a` or `'b` +mod test3 { + trait Trait {} + + // Hidden type = Closure['a, 'b, '_#0r] + // Constraints = [('_#0r: 'a), ('_#0r: 'b)] + type Opaque<'a, 'b> + where + (&'a (), &'b ()): Trait, + = impl Sized + 'a + 'b; + + fn define<'a, 'b, 'x>() -> Opaque<'a, 'b> + where + (&'a (), &'b ()): Trait, + 'x: 'a, + 'x: 'b, + { + || {} + } +} + +fn main() {} |