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// Regression test for #80953. Hitting the recursion limit in projection
// is non-fatal. The above code, minimised from wundergraph shows a case
// where this is relied on.
// check-pass
struct AlternateTable {}
struct AlternateQuery {}
pub trait Query {}
pub trait AsQuery {
type Query;
}
impl<T: Query> AsQuery for T {
type Query = Self;
}
impl AsQuery for AlternateTable {
type Query = AlternateQuery;
}
pub trait Table: AsQuery {
type PrimaryKey;
}
impl Table for AlternateTable {
type PrimaryKey = ();
}
pub trait FilterDsl<Predicate> {
type Output;
}
pub type Filter<Source, Predicate> = <Source as FilterDsl<Predicate>>::Output;
impl<T, Predicate> FilterDsl<Predicate> for T
where
T: Table,
T::Query: FilterDsl<Predicate>,
{
type Output = Filter<T::Query, Predicate>;
}
impl<Predicate> FilterDsl<Predicate> for AlternateQuery {
type Output = &'static str;
}
pub trait HandleDelete {
type Filter;
}
impl<T> HandleDelete for T
where
T: Table,
T::Query: FilterDsl<T::PrimaryKey>,
Filter<T::Query, T::PrimaryKey>: ,
{
type Filter = Filter<T::Query, T::PrimaryKey>;
}
fn main() {
let x: <AlternateTable as HandleDelete>::Filter = "Hello, world";
println!("{}", x);
}
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