1 files changed, 15 insertions, 12 deletions

diff --git a/crates/hir_ty/src/infer/expr.rs b/crates/hir_ty/src/infer/expr.rs
index 79bbc5dab..19249973c 100644
--- a/crates/hir_ty/src/infer/expr.rs
+++ b/crates/hir_ty/src/infer/expr.rs
@@ -11,6 +11,7 @@ use hir_def::{
     AssocContainerId, FieldId, Lookup,
 };
 use hir_expand::name::{name, Name};
+use stdx::always;
 use syntax::ast::RangeOp;
 
 use crate::{
@@ -89,12 +90,12 @@ impl<'a> InferenceContext<'a> {
         let substs =
             Substitution::build_for_generics(&generic_params).push(ty.clone()).push(arg_ty).build();
 
-        let trait_env = Arc::clone(&self.trait_env);
+        let trait_env = self.trait_env.env.clone();
         let implements_fn_trait: DomainGoal =
             TraitRef { trait_id: to_chalk_trait_id(fn_once_trait), substitution: substs.clone() }
                 .cast(&Interner);
         let goal = self.canonicalizer().canonicalize_obligation(InEnvironment {
-            value: implements_fn_trait.clone(),
+            goal: implements_fn_trait.clone(),
             environment: trait_env,
         });
         if self.db.trait_solve(krate, goal.value).is_some() {
@@ -298,8 +299,8 @@ impl<'a> InferenceContext<'a> {
                     self.db,
                     self.resolver.krate(),
                     InEnvironment {
-                        value: canonicalized.value.clone(),
-                        environment: self.trait_env.clone(),
+                        goal: canonicalized.value.clone(),
+                        environment: self.trait_env.env.clone(),
                     },
                 );
                 let (param_tys, ret_ty): (Vec<Ty>, Ty) = derefs
@@ -437,8 +438,8 @@ impl<'a> InferenceContext<'a> {
                     self.db,
                     self.resolver.krate(),
                     InEnvironment {
-                        value: canonicalized.value.clone(),
-                        environment: self.trait_env.clone(),
+                        goal: canonicalized.value.clone(),
+                        environment: self.trait_env.env.clone(),
                     },
                 )
                 .find_map(|derefed_ty| {
@@ -513,10 +514,10 @@ impl<'a> InferenceContext<'a> {
                 let inner_ty = self.infer_expr_inner(*expr, &Expectation::none());
                 if let Some(box_) = self.resolve_boxed_box() {
                     let mut sb =
-                        Substitution::builder(generics(self.db.upcast(), box_.into()).len());
+                        Substitution::build_for_generics(&generics(self.db.upcast(), box_.into()));
                     sb = sb.push(inner_ty);
-                    match self.db.generic_defaults(box_.into()).as_ref() {
-                        [_, alloc_ty, ..] if !alloc_ty.value.is_unknown() => {
+                    match self.db.generic_defaults(box_.into()).get(1) {
+                        Some(alloc_ty) if !alloc_ty.value.is_unknown() && sb.remaining() > 0 => {
                             sb = sb.push(alloc_ty.value.clone());
                         }
                         _ => (),
@@ -537,8 +538,8 @@ impl<'a> InferenceContext<'a> {
                                 self.db,
                                 krate,
                                 InEnvironment {
-                                    value: &canonicalized.value,
-                                    environment: self.trait_env.clone(),
+                                    goal: &canonicalized.value,
+                                    environment: self.trait_env.env.clone(),
                                 },
                             ) {
                                 Some(derefed_ty) => {
@@ -936,7 +937,9 @@ impl<'a> InferenceContext<'a> {
             let def: CallableDefId = from_chalk(self.db, *fn_def);
             let generic_predicates = self.db.generic_predicates(def.into());
             for predicate in generic_predicates.iter() {
-                let predicate = predicate.clone().subst(parameters);
+                let (predicate, binders) =
+                    predicate.clone().subst(parameters).into_value_and_skipped_binders();
+                always!(binders == 0); // quantified where clauses not yet handled
                 self.obligations.push(predicate.cast(&Interner));
             }
             // add obligation for trait implementation, if this is a trait method