mirror of https://github.com/rust-lang/rust.git
56 lines
1.7 KiB
Rust
56 lines
1.7 KiB
Rust
//@ revisions: with_clause without_clause
|
|
// Tests that `EvaluatedToOkModuloRegions` from a projection sub-obligation
|
|
// is correctly propagated
|
|
|
|
#![feature(rustc_attrs)]
|
|
|
|
trait MyTrait {
|
|
type Assoc;
|
|
}
|
|
|
|
struct MyStruct;
|
|
|
|
impl MyTrait for MyStruct {
|
|
// Evaluating this projection will result in `EvaluatedToOkModuloRegions`
|
|
// (when `with_clause` is enabled)
|
|
type Assoc = <Bar as MyTrait>::Assoc;
|
|
}
|
|
|
|
struct Bar;
|
|
|
|
// The `where` clause on this impl will cause us to produce `EvaluatedToOkModuloRegions`
|
|
// when evaluating a projection involving this impl
|
|
#[cfg(with_clause)]
|
|
impl MyTrait for Bar where for<'b> &'b (): 'b {
|
|
type Assoc = bool;
|
|
}
|
|
|
|
// This impl tests that the `EvaluatedToOkModuoRegions` result that we get
|
|
// is really due to the `where` clause on the `with_clause` impl
|
|
#[cfg(without_clause)]
|
|
impl MyTrait for Bar {
|
|
type Assoc = bool;
|
|
}
|
|
|
|
// The implementation of `#[rustc_evaluate_where_clauses]` doesn't perform
|
|
// normalization, so we need to place the projection predicate behind a normal
|
|
// trait predicate
|
|
struct Helper {}
|
|
trait HelperTrait {}
|
|
impl HelperTrait for Helper where <MyStruct as MyTrait>::Assoc: Sized {}
|
|
|
|
// Evaluating this 'where' clause will (recursively) end up evaluating
|
|
// `for<'b> &'b (): 'b`, which will produce `EvaluatedToOkModuloRegions`
|
|
#[rustc_evaluate_where_clauses]
|
|
fn test(val: MyStruct) where Helper: HelperTrait {
|
|
panic!()
|
|
}
|
|
|
|
fn foo(val: MyStruct) {
|
|
test(val);
|
|
//[with_clause]~^ ERROR evaluate(Binder { value: TraitPredicate(<Helper as HelperTrait>, polarity:Positive), bound_vars: [] }) = Ok(EvaluatedToOkModuloRegions)
|
|
//[without_clause]~^^ ERROR evaluate(Binder { value: TraitPredicate(<Helper as HelperTrait>, polarity:Positive), bound_vars: [] }) = Ok(EvaluatedToOk)
|
|
}
|
|
|
|
fn main() {}
|