Higher-ranked trait bounds for where clauses

2 files changed, 15 insertions, 12 deletions

diff --git a/crates/hir_ty/src/lower.rs b/crates/hir_ty/src/lower.rs
index 8392cb770..8da56cd11 100644
--- a/crates/hir_ty/src/lower.rs
+++ b/crates/hir_ty/src/lower.rs
@@ -675,7 +675,8 @@ impl GenericPredicate {
         where_predicate: &'a WherePredicate,
     ) -> impl Iterator<Item = GenericPredicate> + 'a {
         match where_predicate {
-            WherePredicate::TypeBound { target, bound } => {
+            WherePredicate::ForLifetime { target, bound, .. }
+            | WherePredicate::TypeBound { target, bound } => {
                 let self_ty = match target {
                     WherePredicateTypeTarget::TypeRef(type_ref) => Ty::from_hir(ctx, type_ref),
                     WherePredicateTypeTarget::TypeParam(param_id) => {
@@ -888,14 +889,13 @@ pub(crate) fn generic_predicates_for_param_query(
         .where_predicates_in_scope()
         // we have to filter out all other predicates *first*, before attempting to lower them
         .filter(|pred| match pred {
-            WherePredicate::TypeBound {
-                target: WherePredicateTypeTarget::TypeRef(type_ref),
-                ..
-            } => Ty::from_hir_only_param(&ctx, type_ref) == Some(param_id),
-            WherePredicate::TypeBound {
-                target: WherePredicateTypeTarget::TypeParam(local_id),
-                ..
-            } => *local_id == param_id.local_id,
+            WherePredicate::ForLifetime { target, .. }
+            | WherePredicate::TypeBound { target, .. } => match target {
+                WherePredicateTypeTarget::TypeRef(type_ref) => {
+                    Ty::from_hir_only_param(&ctx, type_ref) == Some(param_id)
+                }
+                WherePredicateTypeTarget::TypeParam(local_id) => *local_id == param_id.local_id,
+            },
             WherePredicate::Lifetime { .. } => false,
         })
         .flat_map(|pred| {
diff --git a/crates/hir_ty/src/utils.rs b/crates/hir_ty/src/utils.rs
index af880c065..65b79df0d 100644
--- a/crates/hir_ty/src/utils.rs
+++ b/crates/hir_ty/src/utils.rs
@@ -5,7 +5,9 @@ use std::sync::Arc;
 use hir_def::{
     adt::VariantData,
     db::DefDatabase,
-    generics::{GenericParams, TypeParamData, TypeParamProvenance, WherePredicateTypeTarget},
+    generics::{
+        GenericParams, TypeParamData, TypeParamProvenance, WherePredicate, WherePredicateTypeTarget,
+    },
     path::Path,
     resolver::{HasResolver, TypeNs},
     type_ref::TypeRef,
@@ -27,7 +29,8 @@ fn direct_super_traits(db: &dyn DefDatabase, trait_: TraitId) -> Vec<TraitId> {
         .where_predicates
         .iter()
         .filter_map(|pred| match pred {
-            hir_def::generics::WherePredicate::TypeBound { target, bound } => match target {
+            WherePredicate::ForLifetime { target, bound, .. }
+            | WherePredicate::TypeBound { target, bound } => match target {
                 WherePredicateTypeTarget::TypeRef(TypeRef::Path(p))
                     if p == &Path::from(name![Self]) =>
                 {
@@ -38,7 +41,7 @@ fn direct_super_traits(db: &dyn DefDatabase, trait_: TraitId) -> Vec<TraitId> {
                 }
                 _ => None,
             },
-            hir_def::generics::WherePredicate::Lifetime { .. } => None,
+            WherePredicate::Lifetime { .. } => None,
         })
         .filter_map(|path| match resolver.resolve_path_in_type_ns_fully(db, path.mod_path()) {
             Some(TypeNs::TraitId(t)) => Some(t),