Fix another crash from wrong binders

Basically, if we had something like `dyn Trait<T>` (where `T` is a type
parameter) in an impl we lowered that to `dyn Trait<^0.0>`, when it should be
`dyn Trait<^1.0>` because the `dyn` introduces a new binder. With one type
parameter, that's just wrong, with two, it'll lead to crashes.

1 files changed, 5 insertions, 5 deletions

diff --git a/crates/ra_hir_ty/src/traits/chalk.rs b/crates/ra_hir_ty/src/traits/chalk.rs
index 60d70d18e..e00a82db2 100644
--- a/crates/ra_hir_ty/src/traits/chalk.rs
+++ b/crates/ra_hir_ty/src/traits/chalk.rs
@@ -17,7 +17,7 @@ use ra_db::{
 use super::{builtin, AssocTyValue, Canonical, ChalkContext, Impl, Obligation};
 use crate::{
     db::HirDatabase, display::HirDisplay, method_resolution::TyFingerprint, utils::generics,
-    ApplicationTy, GenericPredicate, ProjectionTy, Substs, TraitRef, Ty, TypeCtor,
+    ApplicationTy, DebruijnIndex, GenericPredicate, ProjectionTy, Substs, TraitRef, Ty, TypeCtor,
 };
 
 pub(super) mod tls;
@@ -815,7 +815,7 @@ pub(crate) fn associated_ty_data_query(
     // Lower bounds -- we could/should maybe move this to a separate query in `lower`
     let type_alias_data = db.type_alias_data(type_alias);
     let generic_params = generics(db.upcast(), type_alias.into());
-    let bound_vars = Substs::bound_vars(&generic_params);
+    let bound_vars = Substs::bound_vars(&generic_params, DebruijnIndex::INNERMOST);
     let resolver = hir_def::resolver::HasResolver::resolver(type_alias, db.upcast());
     let ctx = crate::TyLoweringContext::new(db, &resolver)
         .with_type_param_mode(crate::lower::TypeParamLoweringMode::Variable);
@@ -849,7 +849,7 @@ pub(crate) fn trait_datum_query(
     let trait_data = db.trait_data(trait_);
     debug!("trait {:?} = {:?}", trait_id, trait_data.name);
     let generic_params = generics(db.upcast(), trait_.into());
-    let bound_vars = Substs::bound_vars(&generic_params);
+    let bound_vars = Substs::bound_vars(&generic_params, DebruijnIndex::INNERMOST);
     let flags = chalk_rust_ir::TraitFlags {
         auto: trait_data.auto,
         upstream: trait_.lookup(db.upcast()).container.module(db.upcast()).krate != krate,
@@ -888,7 +888,7 @@ pub(crate) fn struct_datum_query(
         .as_generic_def()
         .map(|generic_def| {
             let generic_params = generics(db.upcast(), generic_def);
-            let bound_vars = Substs::bound_vars(&generic_params);
+            let bound_vars = Substs::bound_vars(&generic_params, DebruijnIndex::INNERMOST);
             convert_where_clauses(db, generic_def, &bound_vars)
         })
         .unwrap_or_else(Vec::new);
@@ -934,7 +934,7 @@ fn impl_def_datum(
     let impl_data = db.impl_data(impl_id);
 
     let generic_params = generics(db.upcast(), impl_id.into());
-    let bound_vars = Substs::bound_vars(&generic_params);
+    let bound_vars = Substs::bound_vars(&generic_params, DebruijnIndex::INNERMOST);
     let trait_ = trait_ref.trait_;
     let impl_type = if impl_id.lookup(db.upcast()).container.module(db.upcast()).krate == krate {
         chalk_rust_ir::ImplType::Local